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Post-term birth and the risk of behavioural and emotional problems in early childhood

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Post-term birth, defined as birth after pregnancy duration of 42 weeks, is associated with increased neonatal morbidity and mortality. The long-term consequences of post-term birth are unknown. We assessed the association of post-term birth with problem behaviour in early childhood. The study was performed in a large population-based prospective cohort study in Rotterdam, The Netherlands. Pregnant mothers enrolled between 2001 and 2005. Of a cohort of 5145 children, 382 (7%) were born post-term, and 226 (4%) were born preterm. Parents completed a standardized and validated behavioural checklist (Child Behavior Checklist, CBCL/1.5-5) when their children were 1.5 and 3 years old. We examined the relation between gestational age (GA) at birth, based on early fetal ultrasound examination, and problem behaviour with regression analyses, adjusting for socio-economic and pregnancy-related confounders. A quadratic relationship between GA at birth and problem behaviour indicates that both preterm and post-term children have higher behavioural and emotional problem scores than the term born children. Compared with term born children, post-term born children had a higher risk for overall problem behaviour [odds ratio (OR) = 2.10, 95% confidence interval (CI) = 1.32-3.36] and were almost two and a half times as likely to have attention deficit / hyperactivity problem behaviour (OR = 2.44, 95% CI = 1.38-4.32). Post-term birth was associated with more behavioural and emotional problems in early childhood, especially attention deficit / hyperactivity problem behaviour. When considering expectant management, this aspect of post-term pregnancy should be taken into account.
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Post-term birth and the risk of behavioural
and emotional problems in early childhood
Hanan El Marroun,
1,2
* Mijke Zeegers,
1,3
Eric AP Steegers,
4
Jan van der Ende,
1
Jacqueline J Schenk,
5
Albert Hofman,
6
Vincent WV Jaddoe,
2,6,7
Frank C Verhulst
1
and Henning Tiemeier
1,6,8
1
Department of Child and Adolescent Psychiatry, Erasmus MC—Sophia, Rotterdam, The Netherlands,
2
The Generation R Study
Group, Erasmus MC, Rotterdam, The Netherlands,
3
Pallas Health Research and Consultancy, Rotterdam, The Netherlands,
4
Department of Obstetrics and Gynecology, Erasmus MC, Rotterdam, The Netherlands,
5
Department of Psychology, Erasmus
University Rotterdam, The Netherlands,
6
Department of Epidemiology, Erasmus MC, Rotterdam, The Netherlands,
7
Department of
Pediatrics, Erasmus MC, Rotterdam, The Netherlands and
8
Department of Psychiatry, Erasmus MC, Rotterdam, The Netherlands
*Corresponding author. Department of Child and Adolescent Psychiatry, Erasmus MC—Sophia, P.O. Box 2060, 3000 CB Rotterdam,
The Netherlands. Email: h.marrounel@erasmusmc.nl
Accepted 23 February 2012
Background Post-term birth, defined as birth after pregnancy duration of
42 weeks, is associated with increased neonatal morbidity and mor-
tality. The long-term consequences of post-term birth are unknown.
We assessed the association of post-term birth with problem behav-
iour in early childhood.
Methods The study was performed in a large population-based prospective
cohort study in Rotterdam, The Netherlands. Pregnant mothers en-
rolled between 2001 and 2005. Of a cohort of 5145 children,
382 (7%) were born post-term, and 226 (4%) were born preterm.
Parents completed a standardized and validated behavioural check-
list (Child Behavior Checklist, CBCL/1.5–5) when their children
were 1.5 and 3 years old. We examined the relation between ges-
tational age (GA) at birth, based on early fetal ultrasound examin-
ation, and problem behaviour with regression analyses, adjusting
for socio-economic and pregnancy-related confounders.
Results A quadratic relationship between GA at birth and problem behav-
iour indicates that both preterm and post-term children have higher
behavioural and emotional problem scores than the term born chil-
dren. Compared with term born children, post-term born children
had a higher risk for overall problem behaviour [odds ratio
(OR) ¼2.10, 95% confidence interval (CI) ¼1.32–3.36] and were
almost two and a half times as likely to have attention deficit /
hyperactivity problem behaviour (OR ¼2.44, 95% CI ¼1.38–4.32).
Conclusions Post-term birth was associated with more behavioural and emo-
tional problems in early childhood, especially attention deficit /
hyperactivity problem behaviour. When considering expectant man-
agement, this aspect of post-term pregnancy should be taken into
account.
Keywords Post-term birth, preterm birth, behavioural and emotional problems,
childhood
Published by Oxford University Press on behalf of the International Epidemiological Association
ßThe Author 2012; all rights reserved.
International Journal of Epidemiology 2012;1–9
doi:10.1093/ije/dys043
1
Int. J. Epidemiol. Advance Access published May 2, 2012
at The University of British Colombia Library on May 3, 2012http://ije.oxfordjournals.org/Downloaded from
Introduction
Timely onset of labour is important for peri- and
post-natal health. Both preterm (<37 weeks of gesta-
tion) and post-term birth (542 weeks of gestation)
are associated with neonatal morbidity and mortal-
ity.
1–3
Local management protocols with regard to
elective caesarean delivery and labour induction
affect the prevalence of post-term birth. Overall,
labour induction before or at 42 weeks of gestation
has increased,
1
but post-term births still occur rela-
tively frequently (up to 5–10%), even in industrialized
countries.
3,4
Accurate pregnancy dating is critical to
the diagnosis of post-term births.
3,4
Routine use of
ultrasound to confirm pregnancy dating can decrease
occurrence of post-term birth.
5
Common risk factors
for post-term birth include obesity, nulliparity and
prior post-term birth and rare causes include placental
sulphatase deficiency (an X-linked recessive disorder
characterized by low estriol levels), fetal adrenal
hypoplasia or insufficiency and trisomy 16
and 18.
1,2,6,7
The long-term problems associated with preterm
birth, such as increased incidence of cerebral palsy,
sensory impairments and behavioural problems are
well known.
8
The studies investigating effects of
post-term birth have focused on the risks during preg-
nancy and delivery.
9
Post-term birth increased the
risk of neonatal encephalopathy and death during
the first year of life,
5,10
but the long-term conse-
quences are unclear. One of the few studies per-
formed found that post-term born infants did not
differ from controls at age 2 years regarding general
intelligence, physical milestones and illnesses.
11
However, a recent study using referral to a neurologist
or psychologist as indicator of developmental prob-
lems found that 13% of children born post-term had
a neurological or developmental disorder at the age of
5 years.
12
In this population-based prospective study, we hy-
pothesize that post-term birth is related to behav-
ioural and emotional problems in preschool children.
In order to examine the specificity of the association
between post-term birth and problem behaviour, we
examined specific behavioural and emotional prob-
lems including attention deficit / hyperactivity dis-
order problems (ADHD), affective problems and
pervasive developmental problems.
Materials and methods
This study was embedded within the Generation R
Study, a population-based cohort from fetal life on-
wards.
13
Briefly, pregnant women who were resident
in Rotterdam, The Netherlands, and whose delivery
dates were between April 2002 and January 2006,
were asked by their midwives and gynaecologists to
participate. In the post-natal follow-up of the
Generation R cohort, 7484 live born children and
their prenatally recruited mothers participated.
Post-natally, 38 children died. The remaining 7446
children were eligible for the study. Mothers of 477
children withdrew consent, and mothers of 410 chil-
dren gave restricted consent (i.e. no participation in
questionnaire studies). The remaining mothers of
6559 children gave full consent for post-natal
follow-up. We excluded twin pregnancies, leaving
6422 children who could be contacted. Information
on child behavioural and emotional problems at 18
and/or 36 months was available for 5145 children (re-
sponse rate of 78%). Maternal report at both 18 and
36 months was available for 3840 children, 812
mothers reported at 18 months only and 493 mothers
reported at 36 months only. The Medical Ethical
Review Board of the Erasmus Medical Centre,
Rotterdam approved the study protocol. All parents
of participating children gave written informed
consent.
Ultrasound during the first visit determined gesta-
tional age (GA) to the nearest day, which will be ex-
pressed in our analyses in weeks. In total, 4132
women (80%) had their first ultrasound examination
in early pregnancy (median 13.1 weeks, range 5.1–
18.0), 868 women (17%) had it in mid-pregnancy
(20.4 weeks, 18.1–25.0) and only 145 women (3%)
had their first ultrasound examination in late preg-
nancy (30.2 weeks, 25.1–39.2). Crown–rump length
was used for pregnancy dating until a GA of 12
weeks and 5 days (crown–rump length <65 mm),
and biparietal diameter was used for pregnancy
dating thereafter (GA from 12 weeks and 5 days on-
wards, biparietal diameter 423 mm). Methods for es-
tablishing GA and standard ultrasound planes for
fetal measurements have been described previously.
14
Inter- and intra-observer intra-class correlation coef-
ficients were all 40.98.
14
Preterm birth was defined as birth before 37 weeks
gestation (N¼226) and post-term birth was defined
as birth after 542 weeks gestation (N¼382). As an
additional comparison group, we defined a group of
children born before 35 weeks of gestation (N¼78)
which is normally included in cohorts of preterm
babies.
The Child Behavior Checklist for toddlers (CBCL/
1.5–5) was used to obtain standardized parental re-
ports of children’s behavioural and emotional prob-
lems.
15,16
The CBCL was a postal questionnaire and
sent to be filled out by the mother when the child
was 18 months old and again when the child was 36
months old. At 36 months of age, we also asked the
father to fill out the CBCL. Each item (99 items in
total) is scored on a three-point scale (0 ¼not true,
1¼somewhat or sometimes true and 2 ¼very true or
often true), based on the child’s behaviour during the
preceding 2 months. The sum of all problem items is
the Total Problems score. There are five Diagnostic
and Statistical Manual of Mental Disorders (DSM)-
oriented scales: anxiety problems, affective problems,
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pervasive developmental problems, ADHD and oppos-
itional defiant problems. It has been shown that these
DSM-oriented scales provide accurate and supplemen-
tary information on clinical diagnoses.
17
Also, good
reliability and validity have been reported for the
CBCL.
16
We used the clinical cut-off scores (91st per-
centile for the Total Problems score and 98th percent-
ile for the syndrome scales) to classify children as
having behavioural problems in the clinical range.
17
When parents filled out the questionnaire, they were
not aware of our research question exploring the re-
lation between post-term birth and behavioural prob-
lems, but parents generally are aware of the GA of
their child and the risks associated with preterm
birth. The maternal CBCL Total Problems ratings at
18 months and 36 months were correlated (r¼0.58,
P< 0.001). Maternal and paternal CBCL Total
Problems ratings at 36 months were correlated
(r¼0.56, P< 0.001).
Several covariates were considered in the analyses
and were chosen based on the existing literature
and effect estimate changes. Maternal weight and
height were measured at intake. We used postal ques-
tionnaires to obtain information on mother’s parity,
ethnicity and family income. Maternal ethnicity was
defined according to the classification of Statistics
Netherlands.
18
Educational level was categorized into
three levels: primary, secondary and higher educa-
tion.
19
Information about maternal smoking and alco-
hol use was obtained by questionnaires in each
trimester. Based on these questionnaires, maternal
smoking or drinking were categorized into ‘no’,
‘until pregnancy was known’ and ‘continued during
pregnancy’ as described previously.
20
The Brief
Symptom Inventory (BSI) was used to assess mater-
nal psychopathology in mid-pregnancy; the BSI is a
validated self-report questionnaire, which defines a
spectrum of psychiatric symptoms.
21
Registries pro-
vided information on obstetric variables such as in-
duction, birthweight, mode of delivery, umbilical
artery pH and Apgar scores after 1 and 5 min. The
post-natal questionnaire administered at age 6 and
12 months was used to gather information on breast-
feeding and frequency of day care use.
For descriptive analyses, children were categorized
in three groups based on GA: (i) born after 37 weeks
of gestation up to and including 41 weeks and 6 days
(term, reference group); (ii) born after <37 weeks of
gestation (preterm); and (iii) born after 42 þ0 weeks
of gestation or more (post-term). Chi-square and
t-tests were used to compare maternal and child char-
acteristics. To test the associations between GA and
behavioural problems, we used linear regression
models with GA as a continuous variable. We used
the generalized estimating equation (GEE) to analyse
the relation of GA with the behavioural and emo-
tional outcomes measured at different time points.
GEE adjusts for auto-correlation within the same
subject. We used an unstructured correlation matrix,
and thus no assumptions were made about the cor-
relations. The GEE procedure provides a more precise
effect estimate and reduces the error derived from
multiple comparisons (Type I error). A quadratic
term was added to the linear regression models to
test whether the associations between GA and behav-
ioural problems were curvilinear. We conducted the
primary analyses in all children, thus also including
the children whose GA was assessed in the second
and third trimester. This was done to reduce the
risk of potential selection bias. Furthermore, we
reran the analyses including only those children
with a GA dating in early pregnancy (N¼4132), be-
cause GA dating by ultrasound is assumed to be more
accurate in early pregnancy.
5
Moreover, we performed linear regression analyses
for maternal ratings at 18 and 36 months separately
to assess whether the quadratic association between
GA at birth and child total problems was present at
both ages. We also performed the same linear regres-
sion analyses for paternal ratings at 36 months. The
results of these analyses can be found in the
Supplementary data, available at IJE online.
Both linear and quadratic analyses were rerun after
exclusion of the preterm children, to ascertain that
the relationship between GA and behavioural prob-
lems was not solely driven by the preterm children.
In addition, we restricted the analyses to the children
born after 39 weeks of gestation. To check whether
results were not unduly influenced by ethnicity, we
reran analyses regarding the Total Problems score
including only the indigenous Dutch children.
Gender-specific estimates for the quadratic association
between GA at birth and child behavioural problems
are provided in the Supplementary Table S1, available
as Supplementary data at IJE online.
For logistic regression analyses, scales were dichot-
omized using the clinical cut-offs. We further
explored the nature of the association between GA
and behavioural problems with the GEE approach,
and calculated the odds ratios (ORs) of clinical prob-
lem behaviour for pre- and post-term born children.
We analysed only those scales on which 40.5% of the
participants were classified as having clinical prob-
lems; these were the ADHD, affective problems and
pervasive developmental problems scales.
Potential confounders were chosen based on the lit-
erature and effect estimate changes. Both linear and
logistic regression models were adjusted for child
gender, maternal age, education, ethnicity, psycho-
pathology, smoking and drinking during pregnancy,
family income and age of the child at the time of
assessments of the CBCL. Maternal weight, height,
parity, breastfeeding and day care did not change
the effect estimates (<5%). Maternal age, psycho-
pathology and age of the child were used as continu-
ous variables. Maternal education, ethnicity, smoking,
drinking and family income were used as categorical
variables in the analyses.
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Several post-hoc analyses were performed,
including only post-term children without induction,
without assisted extraction or no high birthweight
(44000 g) to test if effects were driven by these
birth characteristics.
Not all variables were available for each participant,
the mean proportion of missing values was 5.1% and
these were imputed. Variables were centred and miss-
ing data were imputed with the mean or, for categor-
ical variables, dummy variables were made. The
association between GA at birth and child behaviour
problems of the imputed and non-imputed data set
were compared, and these associations were similar.
Therefore, we only report results of analyses with the
imputed data.
For the non-response analysis, we compared mater-
nal and child characteristics of included partici-
pants with participants from whom we did not
obtain behavioural data. Non-responders were lower
educated (14.7% primary education vs 6.3%,
P< 0.001), younger (maternal age 28.1 vs 31.2
years, P< 0.001), more likely to be non-Dutch (62.0
vs 35.4%, P< 0.001). Excluded infants had a lower
birthweight (3313 vs 3431 g, P< 0.001) and were
born after a shorter period of gestation (39.5 vs 39.8
weeks, P< 0.001), compared with included infants.
The proportion of children born post-term was lower
in the non-response group than in the response group
(5.8 vs 6.9%, P< 0.001).
Results
Table 1 compares demographic and birth characteris-
tics of 5145 children of whom 4537 (88.2%) were
born at term, 382 were born post-term (7.4%) and
226 were born preterm (4.4%).
In Figure 1, the unadjusted associations between the
Total Problems scale and GA at age 18 and 36 months
are shown. The curves show a nadir of the Total
Problems score in children born with a GA around
40 weeks, whereas the mean problem scores are
higher in children who are born more preterm or
more post-term. In addition, we present a scatterplot
of the correlation between GA at birth and Total
Problems score in the Supplementary data, available
at IJE online.
For continuous scores on the total problems, ADHD,
affective problems scales and pervasive developmen-
tal problems, linear regression analyses showed a
curvilinear relation between GA and behavioural prob-
lems, indicating that children with shorter or longer
gestation had higher behavioural problem scores com-
pared with children born at term (Table 2). After exclu-
sion of the preterm born children, the curvilinear
relations between GA and behavioural problems re-
mained, showing that mean problem scores were
higher in children with a longer GA [Total Problems
score GA
2
¼0.34, 95% confidence interval (CI) ¼
0.14–0.54]. When we restricted the analyses to the
children born after 39 weeks of gestation (n¼4115),
we still observed a linear association between GA at
birth and total child behavioural and emotional prob-
lems (data not shown).
Supplementary analyses demonstrated that results
were similar when children with second or third tri-
mester GA dating were excluded (Total Problems
score GA
2
¼0.12, 95% CI ¼0.06–0.18). Moreover,
analyses on the Total Problems score were rerun in
a smaller subset of Dutch children; the results were
somewhat similar (GA
2
¼0.08, 95% CI ¼0.01–0.12).
In addition, there was no interaction between GA and
the two time points of CBCL measurement indicating
that effects remained stable over early childhood
(data not shown).
Separate linear regression analyses using the two
maternal ratings each demonstrated that the quad-
ratic association between GA at birth and child be-
havioural problems was present at 18 and 36 months
(Supplementary Table S2, available as Supplementary
data at IJE online). Analyses using the paternal rat-
ings of child behavioural and emotional problems also
demonstrated a quadratic relationship between GA at
birth and child emotional and behavioural outcomes
(Supplementary Table S3, available as Supplementary
data at IJE online).
Table 3 shows that post-term children were almost
twice as likely as term born children to have clinical
problem behaviour on the Total Problems scale and
were more likely to have problems in the clinical
range on the ADHD scale. Compared with term born
children, post-term children did not have higher ORs
on the affective problems or pervasive developmental
problems scales.
The preterm group showed considerably more be-
havioural or emotional problems compared with the
term group; this group was more likely to develop
problems on the Total Problems scale and the ADHD
scale. With a more stringent cut-off for preterm birth
(<35 weeks), we found that these children were more
likely to have problems in the clinical range on the
Total Problems scale, ADHD scale and the pervasive
developmental problems scale.
In addition, some groups of children were excluded
from the analyses. These exclusions did not change
the results. The risk for developing total problems in
children born post-term remained present after
excluding children with induction (OR ¼1.77, 95%
CI ¼1.01–3.10) or after excluding children 44000 g
of birth weight (OR ¼1.83, 95% CI ¼1.06–3.15).
Discussion
Our study demonstrated that children born post-term
were more likely than their term born peers to have
emotional and behavioural problems at both 18 and
36 months after birth.
Post-term delivery and behavioural problems could
be explained in several pathways. First, a larger baby
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Table 1 Maternal and child characteristics in the study population
Term
a
N¼4537 Post-term
a
N¼382 Preterm
a
N¼226
Mean (SD) or % Mean (SD) or % P(to ref) Mean (SD) or % P(to ref)
Maternal characteristics
Age, mean years (SD) 31 (5) 31 (5) 0.34 31 (5) 0.55
Education level, %
Primary education 6.9 5.8 0.46 7.1 0.89
Secondary education 37.8 31.4 0.01 39.8 0.57
Higher education 52.0 59.2 <0.01 47.3 0.20
Ethnicity, %
Dutch 59.3 63.4 0.13 52.7 0.05
Other Western 8.6 10.5 0.22 8.0 0.90
Turkish, Moroccan 11.1 11.5 0.80 10.6 0.91
Surinamese, Antillean 8.1 5.9 <0.01 10.6 0.17
Psychopathology, mean score (SD) 0.25 (0.3) 0.23 (0.3) 0.43 0.28 (0.4) 0.15
Marital status, % single 9.4 7.8 0.35 14.8 0.01
Parity 41, % 12.2 10.2 0.15 8.4 0.09
Family income, %
<E1200 11.5 10.5 0.62 18.1 <0.01
4E1200 and <E2000 14.7 12.0 0.17 14.6 1.00
4E2000 63.4 67.5 0.11 53.5 <0.01
Smoking throughout pregnancy % 14.6 14.4 1.0 18.6 0.15
Alcohol use throughout pregnancy, % 46.8 52.9 0.03 44.9 0.62
Breastfeeding at 2 months, % 68.8 71.5 0.31 63.5 0.12
Child characteristics
GA, mean weeks (SD) 40.0 (1.1) 42.3 (0.3) <0.001 35.0 (2.0) <0.001
Range 37.0–41.9 42.0–43.4 26.7–36.9
Birthweight, mean grams (SD) 3481 (486) 3819 (456) <0.001 2403 (604) <0.001
Boys, % 49.1 58.4 <0.001 46.0 0.15
Suspected fetal distress, % 6.9 15.2 <0.001 13.5 <0.001
Hospital delivery, % 79.1 89.5 <0.001 96.4 <0.001
Labour induction, % 9.7 37.1 <0.001 12.9 0.16
Meconium in amniotic fluid, % 15.8 18.0 0.15 0.9 <0.001
Assisted delivery, % 8.6 30.6 <0.001 13.4 0.033
Caesarean delivery, % 11.6 18.2 <0.001 25.3 <0.001
Apgar 5 min <7, % 1.0 0.8 0.51 0.9 1.00
pH umbilical artery <7.1, % 3.8 3.3 0.45 2.9 0.68
Behavioural scores measured with CBCL
b
Total problems
Score at 18 months 23.53 (15.66) 24.47 (16.71) 0.29 28.35 (17.73) <0.001
Score at 36 months 20.52 (15.07) 22.29 (15.02) 0.04 24.10 (17.34) 0.002
ADHD
Mean score (SD) at 18 months 3.86 (2.45) 4.00 (2.45) 0.33 4.51 (2.56) <0.001
Mean score (SD) at 36 months 2.95 (2.32) 3.08 (2.31) 0.36 3.43 (2.63) 0.007
Affective problems
Mean score (SD) at 18 months 1.56 (1.69) 1.73 (1.90) 0.12 2.09 (1.91) <0.001
Mean score (SD) at 36 months 1.41 (1.58) 1.55 (1.62) 0.12 1.78 (1.76) 0.002
Pervasive developmental problems
Mean score (SD) at 18 months 1.73 (2.05) 1.86 (2.15) 0.28 2.27 (2.67) <0.001
Mean score (SD) at 36 months 1.99 (2.26) 2.23 (2.32) 0.06 2.46 (2.87) 0.006
P-values are derived from t-tests for continuous variables and chi-square tests for categorical variables.
a
Categorization was based on GA at birth, term (GA from 37 weeks up to 42 weeks), preterm (GA <37 weeks) and post-term (GA of 42 weeks or more).
b
Behavioural and emotional problem scores were measured using the CBCL reported by mother at 18 and 36 months.
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typically has a higher risk for perinatal problems.
Prolonged labour, cephalopelvic disproportion and
shoulder dystocia are increased in post-term chil-
dren.
2
A perinatal lack of oxygen has been associated
with behavioural problems.
22
However, our results did
not suggest increased fetal stress in the post-term
children, as indicated by low Apgar score, low umbil-
ical pH or meconium-stained amniotic fluid. We con-
trolled for several birth characteristics. Moreover,
exclusion of post-term children with induction and
44000 g of birth weight did not change results. A
second explanation is uteroplacental insufficiency: a
non-optimal ‘old’ placenta offers fewer nutrients and
less oxygen than a full term fetus requires.
1
The lack
of nutrients and oxygen may predispose to abnormal
fetal development and this may lead to abnormal
emotional and behavioural development.
23
In our
study, we could not distinguish possible effects of
uteroplacental insufficiency from perinatal problems.
Thirdly, it is possible that a disturbance of the
Figure 1 The unadjusted association between GA at birth and total behavioural and emotional problem score
Table 2 Association between GA at birth and behavioural and emotional problem score (continuous)
Total problems ADHD
Affective
problems
Pervasive
developmental
problems
(95% CI) (95% CI) (95% CI) (95% CI)
Model I
Linear model; GA 0.24 (0.48 to 0.01) 0.04 (0.08 to 0.01) 0.04 (0.06 to 0.10) 0.05 (0.09 to 0.02)
Quadratic model; GA 0.05 (0.21 to 0.32) 0.01 (0.05 to 0.04) 0.00 (0.03 to 0.06) 0.03 (0.06 to 0.01)
GA
2
0.13 (0.06 to 0.20) 0.01 (0.00 to 0.03) 0.02 (0.01 to 0.02) 0.01 (0.00 to 0.03)
Model II
Linear model; GA 0.15 (0.16 to 0.46) 0.01 (0.05 to 0.06) 0.08 (0.03 to 0.04) 0.02 (0.06 to 0.02)
Quadratic model; GA 0.06 (0.39 to 0.28) 0.02 (0.08 to 0.03) 0.01 (0.05 to 0.02) 0.05 (0.09 to 0.01)
GA
2
0.34 (0.14 to 0.54) 0.05 (0.02 to 0.08) 0.03 (0.01 to 0.05) 0.04 (0.02 to 0.07)
Behavioural and emotional problem scores were measured using the CBCL reported by mother at 18 and 36 months.
Model I: included all children.
Model II: included all children born after 37 weeks.
All models were adjusted for maternal age, education, ethnicity, psychopathology, smoking and drinking during pregnancy,
family income, gender of the child and age of the child at the assessment of the CBCL.
gives the estimate of increase in CBCL score per week increase of the centred GA. Bold values represent findings that were
considered statistically significant (P<0.05).
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‘placental clock’, which controls the length of preg-
nancy, is involved. A marker of this clock is the pla-
cental secretion of corticotrophin-releasing hormone
(CRH), which is lower in women who deliver
post-term than in women delivering at term.
24
CRH
is the principal regulator of the maternal and fetal
hypothalamic–pituitary–adrenal (HPA) axis.
25
It has
been suggested that placental endocrine malfunction-
ing or maternal stress at critical times during fetal
development may influence the fetal HPA axis, lead-
ing to neuroendocrine abnormalities that could in-
crease the child’s vulnerability to emotional and
behavioural problems later in life.
26
Finally, the asso-
ciation between post-term birth and childhood behav-
ioural problems could be explained by underlying
causes of being born post-term. In other words, the
cause for post-term could also be the cause for having
behavioural problems, for example neurodevelopmen-
tal factors related to behavioural problems could be
involved in the complex process of birth.
This is a population-based study including many
post-term children. We measured problem behaviour
with the same validated instrument (CBCL/1.5–5) at
two time points. As ultrasound gestational dating is
thought to be superior to last menstrual period-based
gestational dating,
5
we decided to use primarily ultra-
sound dating. Eighty percent of our sample was dated
with ultrasound assessment in early pregnancy.
However, some limitations must be discussed.
Firstly, mothers were not formally blinded for the
GA of their children and they might perceive more
behavioural problems in post-term children.
However, the notion that a post-term birth may
signal at-risk babies is largely non-existent in the
medical profession and absent in the public debate.
Secondly, in the current study, we relied on the CBCL,
as it was not feasible to obtain clinical diagnoses in
such a large number of children. Moreover, these chil-
dren were too young to be assessed by teachers or
other informants, thus we had to rely on parental
ratings that may be biased. Moreover, the CBCL is
not a clinical instrument and cannot provide diag-
noses, but addresses continuous traits in children.
However, the DSM-oriented scales provide accurate
information
17
and good reliability and validity have
been reported.
16
Finally, although we controlled for a large number
of confounders, including maternal smoking, psycho-
pathology and socio-economic characteristics, residual
confounding, for example maternal malnutrition
during pregnancy, cannot be ruled out.
Management of prolonged pregnancy follows two
approaches: proposing induction before 42 weeks of
gestation or close monitoring of pregnancy after 41
weeks with selective induction in case of fetal distress
or a favourable Bishop score.
4
Pregnancy and peri-
natal care are criticized in The Netherlands, as peri-
natal mortality ranks as the third worst in Europe.
27
Until mid-2008, a woman with a low-risk pregnancy
at 42 weeks was referred to a gynaecologist for close
monitoring only. The current revised policy requires a
referral at 41 weeks. Although the rate of post-term
births went down after introducing first trimester
ultrasound dating of GA,
5
post-term delivery remains
common.
4
In conclusion, post-term children have a consider-
ably higher risk of clinically relevant problem behav-
iour. They are more than twice as likely as term born
children to have clinical ADHD. Further research is
needed to determine the causes of post-term birth
to reduce post-term birth rates and to minimize
long-term consequences. Also, longer follow-up is
Table 3 Association between GA at birth and behavioural and emotional problems (clinical cut-off)
Total problems ADHD
Affective
problems
Pervasive
developmental
problems
OR (95% CI) OR (95% CI) OR (95% CI) OR (95% CI)
Term birth N¼4537 1.0 1.0 1.0 1.0
Post-term birth N¼382 1.83 (1.17–2.85) 2.04 (1.18–3.55) 1.48 (0.88–2.51) 1.84 (0.95–3.55)
Preterm birth <37 weeks N¼226 2.35 (1.43–3.88) 2.28 (1.21–4.28) 1.51 (0.83–2.76) 1.83 (0.84–3.97)
Preterm birth <35 weeks N¼78 3.00 (1.48–6.09) 3.42 (1.41–8.32) 1.92 (0.74–4.99) 3.95 (1.47–10.6)
Prevalence of behavioural and emotional problems
Total
problems (%)
ADHD
(%)
Affective
problems (%)
Pervasive developmental
problems (%)
Problems at 18 months 4.2 2.5 3.5 1.8
Problems at 36 months 3.1 1.2 2.5 2.0
Behavioural and emotional problem scores were measured using the CBCL reported by mother at 18 and 36 months.
All models were adjusted for maternal age, education, ethnicity, psychopathology, smoking and drinking during pregnancy, family
income, gender of the child and age of the child at the assessment of the CBCL.
Categorization was based on GA at birth, term (GA from 37 weeks up to 42 weeks), post-term (GA of 42 weeks or more) and
preterm (GA <37 weeks or <35 weeks). Bold values represent findings that were considered statistically significant (P<0.05).
POST-TERM BIRTH AND CHILD PROBLEM BEHAVIOUR 7
at The University of British Colombia Library on May 3, 2012http://ije.oxfordjournals.org/Downloaded from
necessary to establish whether the relationship be-
tween post-term birth and behavioural problems will
persist.
Supplementary Data
Supplementary Data are available at IJE online.
Funding
The Sophia Children’s Hospital Fund (project number
553) and the WH Kro
¨ger Foundation. The first phase
of the Generation R Study is made possible by
financial support from the Erasmus Medical Centre,
the Erasmus University and The Netherlands
Organization for Health Research and Development
(Zon MW, grant ZonMW Geestkracht 10.000.1003).
Acknowledgments
The Generation R Study is conducted by the Erasmus
Medical Centre in close collaboration with the School
of Law and Faculty of Social Sciences of the Erasmus
University Rotterdam, the Municipal Health Service
Rotterdam area, the Rotterdam Homecare
Foundation and the Stichting Trombosedienst &
Artsenlaboratorium Rijnmond (STAR), Rotterdam.
We gratefully acknowledge the contribution of general
practitioners, hospitals, midwives and pharmacies in
Rotterdam. H.E.M. checked the references used in this
article for accuracy and completeness. H.T. will act as
guarantor for the article. Someone with an excellent
mastery of the English language has carefully edited
the article. This article represents original material
and has not been published previously in whole or
in part. In addition, no similar paper is in press or
under review elsewhere.
Conflict of interest: F.C.V. is author and head of the
Department of Child and Adolescent Psychiatry at
Erasmus MC, which publishes the Achenbach
System of Empirically Based Assessment (ASEBA)
and from which he receives remuneration. All other
authors report no conflicts of interest.
KEY MESSAGES
GA at birth and behavioural and emotional problems in early childhood show a non-linear quadratic
relation indicating that both preterm and post-term children are at higher risk for problems.
Children born post-term were twice as likely as their term-born peers to have ADHD in early
childhood.
Our results suggest that children born post-term have a neurodevelopmental delay. However, further
research is needed to demonstrate a causal relation.
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... Post-term birth is associated with significant cognitive delays compared with full-term counterparts (29). Children born post-term were more likely to have emotional and behavioral problems assessed at both 18 and 36 months old compared to their full-term counterparts (8,30). Post-term children also presented increased risk and symptomatology of ASD (8,31) and ADHD (32) during childhood. ...
... More importantly, we found a stronger association between post-term birth and SDD when compared with late-preterm and early-term birth. In recent years, several studies have highlighted the significant negative effect on cognitive delays (29), emotional and behavioral problems (8,30), and developmental disorders of post-term birth (8,31). Our study confirms the negative effect of post-term birth on neurodevelopment in all five domains including problem-solving, communication, fine motor skills, gross motor skills, and personal-social behavior. ...
... First, a larger weight baby at birth, associated with a longer GA, has a higher risk for perinatal problems such as prolonged labor, which can cause a perinatal lack of oxygen, which has been shown to be associated with behavioral problems (69). Second, post-term birth is related to uteroplacental insufficiency (70), and compared with full-term birth, the placenta in post-term birth offers fewer nutrients and less oxygen which is associated with abnormal emotional and behavioral development (30). Finally, previous studies have shown that the placental secretion of corticotrophin-releasing hormone (71), the principal regulator of the maternal and fetal hypothalamic-pituitary-adrenal axis (72) is lower in women who deliver post-term than full-term. ...
Article
Full-text available
Background The association between preterm birth and neurodevelopmental delays have been well examined, however, reliable estimates for the full range of gestational age (GA) are limited, and few studies explored the impact of post-term birth on child development. Objective This study aimed to examine the long-term neuropsychological outcomes of children born in a full range of GA with a national representative sample in China. Methods In this retrospective population-based cohort study, a total of 137,530 preschoolers aged 3–5 years old (65,295/47.5% females and 72,235/52.5% males) were included in the final analysis. The Ages and Stages Questionnaires-Third Edition (ASQ-3) was completed by parents to evaluate children's neurodevelopment. The associations between GA and neurodevelopment were analyzed by a generalized additive mixed model with thin plate regression splines. Logistic regression was also conducted to examine the differences in children's development with different GAs. Results There was a non-linear relationship between GA and children's neurodevelopmental outcomes with the highest scores at 40 weeks gestational age. The adjusted risks of GAs (very and moderately preterm, late-preterm, early-term, and post-term groups) on suspected developmental delays were observed in communication (OR were 1.83, 1.28, 1.13, and 1.21 respectively, each p < 0.05), gross motor skill (OR were 1.67, 1.38, 1.10, and 1.05 respectively, each p < 0.05), and personal social behavior (OR were 1.01, 1.36, 1.12, and 1.18 respectively, each p < 0.05). The adjusted OR of very and moderately preterm, late-preterm, and early-term were observed in fine motor skills (OR were 1.53, 1.22, and 1.09 respectively, each p < 0.05) and problem-solving (OR were 1.33, 1.12, and 1.06 respectively, each p < 0.05). Conclusion GAs is a risk factor for neurodevelopmental delays in preschoolers after controlling for a wide range of covariates, and 40–41 weeks may be the ideal delivery GA for optimal neurodevelopmental outcomes. Close observation and monitoring should be considered for early- and post-term born children as well as pre-term children.
... [11][12][13][14][15][16] Mild and moderate motor impairments occur in almost half of all preterm children (<37 weeks). 17 However, although it has been reported that late preterm children (34)(35)(36) weeks) have more neonatal morbidities than full-term infants 18 and experience neuromotor delay during their first year of life, 19 few studies have explored the association between late preterm birth and DCD in preschool or school-aged children beyond the first year of life. There appear to be inconsistencies in the literature, with studies showing that late preterm infants otherwise born healthy seem to have no delay in their cognition, motor performance, behavior, or socioemotional development throughout childhood, 20,21 whereas other studies report significant differences in neurodevelopment between late preterm and full-term children. ...
... 26,28-31 The number of gestational weeks in the fullterm range has also been found to be associated with neuromotor and motor development in infants aged 9 to 15 weeks 32 and infants aged 12 months. 26 Recently, studies [33][34][35][36][37] have reported that postterm birth (>41 weeks) is negatively associated with a child's short-term and long-term health outcomes. A meta-analysis 38 found that postterm birth is associated with significant negative effects on cognitive measures compared with full-term birth. ...
... Children born post term were more likely to have emotional and behavioral problems at both age 18 and 36 months compared with full-term children. 36 Postterm children were also found to manifest increased risk and symptomatology of autism spectrum disorder 33,39 and attention-deficit/ hyperactivity disorder. 40 However, children born post term were also reported to reach the main developmental milestones in their infancy when compared with full-term children. ...
Article
Full-text available
Importance It remains unknown whether children born at different degrees of prematurity, early term, and post term might have a higher risk of developmental coordination disorder (DCD) compared with completely full-term children (39-40 gestational weeks). Objective To differentiate between suspected DCD in children with different gestational ages based on a national representative sample in China. Design, Setting, and Participants A retrospective cohort study was conducted in China from April 1, 2018, to December 31, 2019. A total of 152 433 children aged 3 to 5 years from 2403 public kindergartens in 551 cities of China were included in the final analysis. A multilevel regression model was developed to determine the strength of association for different gestational ages associated with suspected DCD when considering kindergartens as clusters. Main Outcomes and Measures Children’s motor performance was assessed using the Little Developmental Coordination Disorder Questionnaire, completed by their parents. Gestational age was determined according to the mother’s medical records and divided into 7 categories: completely full term (39 to 40 weeks’ gestation), very preterm (<32 weeks), moderately preterm (32-33 weeks), late preterm (34-36 weeks), early term (37-38 weeks), late term (41 weeks), and post term (>41 weeks). Results A total of 152 433 children aged 3 to 5 years (mean [SD] age, 4.5 [0.8] years), including 80 370 boys (52.7%) and 72 063 girls (47.3%), were included in the study. There were 45 052 children (29.6%) aged 3 years, 59 796 (39.2%) aged 4 years, and 47 585 (31.2%) aged 5 years. Children who were born very preterm (odds ratio [OR], 1.35; 95% CI, 1.23-1.48), moderately preterm (OR, 1.18; 95% CI, 1.02-1.36), late preterm (OR, 1.24; 95% CI, 1.16-1.32), early term (OR, 1.11; 95% CI, 1.06-1.16), and post term (OR, 1.17; 95% CI, 1.07-1.27) were more likely to be classified in the suspected DCD category on the Little Developmental Coordination Disorder Questionnaire than completely full-term children after adjusting for the same characteristics. Additionally, there was no association with suspected DCD in younger (aged 3 years) early-term and postterm children by stratified analyses. Conclusions and Relevance In this cohort study, every degree of prematurity at birth, early-term birth, and postterm birth were associated with suspected DCD when compared with full-term birth. These findings have important implications for understanding motor development in children born at different gestational ages. Long-term follow-up and rehabilitation interventions should be considered for children born early and post term.
... Moreover, to our knowledge, no study has been conducted to date on the sleep outcomes of post-term-born children (>41 weeks). Studies have reported that postterm birth can negatively affect children's short-term and long-term health outcomes [11][12][13][14][15]. Post-term birth can increase the risk of neonatal encephalopathy and death during the first year of life [16]. ...
... One important finding of the current study is that an association between post-term birth (>41 weeks) and altered sleep outcomes were observed. Previous studies have suggested that post-term birth may be associated with a range of adverse neurological, developmental, behavioural and emotional outcomes in early childhood [14,19,61]. Mechanisms concerning post-term birth with a higher risk of sleep disorder and shorter daily sleep hours might involve placental deterioration or insufficiency causing foetal hypoxia or nutritional deficiencies, which in turn could result in injury to the foetal brain [62]. ...
Article
Full-text available
Abstract Background Both sleep quality and quantity are essential for normal brain development throughout childhood; however, the association between preterm birth and sleep problems in preschoolers is not yet clear, and the effects of gestational age across the full range from preterm to post-term have not been examined. Our study investigated the sleep outcomes of children born at very-preterm (41 weeks). Methods A national retrospective cohort study was conducted with 114,311 children aged 3–5 years old in China. Children’s daily sleep hours and pediatric sleep disorders defined by the Children’s Sleep Habits Questionnaire (CSHQ) were reported by parents. Linear regressions and logistic regression models were applied to examine gestational age at birth with the sleep outcomes of children. Results Compared with full-term children, a significantly higher CSHQ score, and hence worse sleep, was observed in very-preterm (β = 1.827), moderate-preterm (β = 1.409), late-preterm (β = 0.832), early-term (β = 0.233) and post-term (β = 0.831) children, all p41) was also seen in very-preterm (adjusted odds ratio [AOR] = 1.287 95% confidence interval [CI] (1.157, 1.433)), moderate-preterm (AOR = 1.249 95% CI (1.110, 1.405)), late-preterm (AOR = 1.111 95% CI (1.052, 1.174)) and post-term (AOR = 1.139 95% CI (1.061, 1.222)), all p
... Previous studies have suggested that postterm pregnancy may be associated with offspring's growth and development (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). Postterm pregnancy was associated with poorer developmental outcomes including lower cognitive ability and academic achievement (11,12), more behavioral and emotional problems (13), and higher risk of developmental vulnerability (14)(15)(16), intellectual disability (17), and cerebral palsy (18)(19)(20) in children. ...
... Previous studies have suggested that postterm pregnancy may be associated with offspring's growth and development (11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22). Postterm pregnancy was associated with poorer developmental outcomes including lower cognitive ability and academic achievement (11,12), more behavioral and emotional problems (13), and higher risk of developmental vulnerability (14)(15)(16), intellectual disability (17), and cerebral palsy (18)(19)(20) in children. Nevertheless, research evidence on the association between postterm pregnancy and offspring's growth status during childhood is rare. ...
Article
Full-text available
Background: Postterm pregnancy has been associated with higher risk of perinatal mortality and morbidity, but its long-term health effects on offspring are poorly understood. Objectives: The aim of the study was to investigate the prospective associations between maternal postterm pregnancy and adverse growth outcomes in children. Methods: The Jiaxing Birth Cohort is part of a large population-based health surveillance system in China and recruited pregnant females resident in the Jiaxing area between 1999 and 2013; newborns were followed up for a median duration of 5.8 y until they went to school. Mother-child pairs with maternal gestational information and offspring's anthropometric data at 4-7 y old were included. Postterm pregnancy was defined as maternal gestational age ≥42 and <47 wk, and its associations with offspring obesity, overweight/obesity, and thinness during childhood were determined by using Poisson regression models. Results: Of the 101,505 included mother-child pairs, 2369 (2.3%) children were born at postterm. Children born at postterm had significantly lower BMI-for-age z score, weight-for-age z score, and height-for-age z score than those born at term; the mean difference (95% CI) was -0.11 (-0.15, -0.06), -0.17 (-0.21, -0.13), and -0.16 (-0.20, -0.12), respectively. When comparing postterm with term pregnancy, the multivariable-adjusted RRs and 95% CIs among preschool-age children were 0.87 (0.68, 1.11) for obesity, 0.82 (0.72, 0.94) for overweight/obesity, and 1.18 (1.09, 1.28) for thinness, respectively. These risk estimates were robust in sensitivity analyses, but were attenuated in several subgroups stratified by age, sex, mode of delivery, and fetal distress. Conclusions: Postterm pregnancy was associated with a higher risk of thinness, and a lower risk of overweight/obesity, as well as lower growth parameters in preschool-age children. These findings imply that postterm pregnancy may impede the long-term growth of offspring.
... Although the risk was largest for very preterm individuals, it increased with deviation from 40 weeks of GA including MLPT and post-term individuals. Furthermore, individuals born post-term show long-term emotional problems and a higher risk for clinically relevant problem behaviour compared to full-term counterparts (El Marroun et al., 2012), thereby highlighting the need to investigate this population with regard to autism symptomology. To date only one study compared full-and post-term children with autism and reported a higher symptom severity in the latter (Movsas & Paneth, 2012). ...
... Post-term birth was a risk factor for autism diagnosis in our study. However, it was not associated with a different phenotypic expression of autism in our study although a higher autism severity (Movsas & Paneth, 2012), more behavioural and emotional problems (El Marroun et al., 2012) and a higher rate of neurodevelopmental disorders (Katarina Lindström et al., 2005) were previously reported in this population. Contrary to this, Gardener and colleagues (2011) argue that post-term birth is in fact a strong protective factor with regard to the risk of developing autism, therefore also buffering adverse effects. ...
Article
Full-text available
Pre- and post-term children show increased autism risk. Little is known about gestational age (GA) prevalence among autistic children, and their respective autism phenotype. We compared prevalence of pre-, full- and post-term birth between a population-derived sample of N = 606 (137 females, 22.61%) autistic children and adolescents (mean age = 14.01, SD = 3.63, range 3–24) from the Netherlands Autism Register , and matched controls from the Dutch birth register. Autism phenotype and comorbid symptoms were assessed with the AQ-short and SDQ questionnaires. Using logistic regression, we found higher prevalence of pre- and post-term birth among autistic individuals but no phenotypical differences across GA groups. Autism risk was particularly elevated for post-term children, highlighting the need for closer investigation of autism on the whole GA range.
... The researchers found that stillbirths steadily rose with gestational age, from 0.11 per thousand births at 37 weeks to 3.18 per thousand at 42 weeks. After 40 weeks of pregnancy, the risk of stillbirth rises [4,5]. After 37 weeks of pregnancy, the placenta reaches its maximum size and its functions begin to reduce. ...
... Post-term births increase risk of poor childhood health (eg, respiratory distress, fetal macrosomia, dysmaturity syndrome, poorer physical function 34 ), which can directly contribute to lower engagement in higher intensity activities in both school and extracurricular settings. 35 Additionally, oxygen deficiency and abnormal neuroendocrine environment in post-term pregnancies may contribute to increased risk of behavioural and emotional problems, 36 which are more common in boys and linked to physical inactivity. 37 Males born post-term also have higher risk of obesity in adolescence, which is both affected by and subsequently to low levels of physical activity throughout the life course. ...
Article
Full-text available
Background It is hypothesised that lifelong physical activity behaviours are established in early life, however there is minimal, and contradictory, evidence examining prenatal and postnatal factors in relation to adulthood physical activity. We investigated associations between prospectively ascertained prenatal/postnatal factors and device-measured moderate-to-vigorous physical activity (MVPA) in midlife. Methods Analyses included 5011 participants from the 1970 British Cohort Study, a birth cohort study of individuals born within the same week. At birth, the following factors were ascertained: socioeconomic position (SEP), maternal age, number of previous pregnancies, maternal smoking, maternal diabetes, gestational age, birth weight, breastfeeding status and infant health concerns. MVPA was captured at age 46 with a thigh-worn accelerometer device following a 24-hour protocol over 7 days. Results In sex-adjusted models, lower SEP (−6.7 min/day (95% CI: −9.0 to –4.4) in those with a partly or unskilled paternal occupation), younger maternal age (0.4 min/day (0.2 to 0.5) per additional year of maternal age), maternal smoking during pregnancy (−2.5 min/day (−4.0 to –1.0)) and post-term gestational age (−7.4 min/day (−11.5 to –3.4); boys only) were associated with lower MVPA at age 46. In the mutually adjusted model, associations did not change but there was some evidence that birth weight may also be associated with MVPA levels. Conclusions SEP, maternal age, maternal smoking, post-term birth in boys and birth weight were associated with MVPA in midlife, indicating that midlife physical activity behaviours may be partially established at birth. Early interventions in disadvantaged environments may have a positive impact on physical activity throughout the life course.
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Recent increases in prescriptions and illegal drug use as well as exposure to environmental contaminants during pregnancy have highlighted the critical importance of placental toxicology in understanding and identifying risks to both mother and fetus. Although advantageous for basic science, current in vitro models often fail to capture the complexity of placental response, likely due to their inability to recreate and monitor aspects of the microenvironment including physical properties, mechanical forces and stiffness, protein composition, cell-cell interactions, soluble and physicochemical factors, and other exogenous cues. Tissue engineering holds great promise in addressing these challenges and provides an avenue to better understand basic biology, effects of toxic compounds and potential therapeutics. The key to success lies in effectively recreating the microenvironment. One strategy to do this would be to recreate individual components and then combine them. However, this becomes challenging due to variables present according to conditions such as tissue location, age, health status and lifestyle. The extracellular matrix (ECM) is known to influence cellular fate by working as a storage of factors. Decellularized ECM (dECM) is a recent tool that allows usage of the original ECM in a refurbished form, providing a relatively reliable representation of the microenvironment. This review focuses on using dECM in modified forms such as whole organs, scaffold sheets, electrospun nanofibers, hydrogels, 3D printing, and combinations as building blocks to recreate aspects of the microenvironment to address general tissue engineering and toxicology challenges, thus illustrating their potential as tools for future placental toxicology studies.
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Background Emotional and behavioral problems (EBP) are common in children. Environmental factors like socioeconomic disadvantage influence EBP pathogenesis and can trigger inflammation. However, the link between early inflammation-EBP in children is unclear. We investigated the associations between i) infant inflammatory biomarkers and subsequent EBP and ii) early life environmental factors and EBP and assessed whether infant inflammation mediated these associations. Methods Inflammatory biomarkers glycoprotein acetyls (GlycA) and high-sensitivity C-reactive protein (hsCRP) were quantified at birth and 12 months in a population–derived birth cohort, the Barwon Infant Study. Early life factors including demographic, prenatal, and perinatal factors, were collected from antenatal to the two-year period. Internalizing and externalizing at age two were measured by the Child Behavior Checklist. Prospective associations were examined by multivariable regression analyses adjusted for potential confounders. Indirect effects of early life factors on EBP through inflammation were identified using mediation analyses. Results Elevated GlycA levels at birth (GlycAbirth) were associated with greater internalizing problems at age two (β=1.32 per SD increase in GlycA; P=0.001). Inflammation at birth had a stronger magnitude of effect with later EBP than at 12 months. GlycAbirth partially mediated the associations between lower household income (6%), multiparity (12%) and greater number of older siblings (13%) and EBP. Patterns were less evident for hsCRP and externalizing problems. Conclusions GlycAbirth was positively associated with EBP at age two and partially mediated the association between several indicators of socioeconomic disadvantage and EBP. Prenatal and perinatal inflammation may be relevant to early neurodevelopment and emotional health.
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Objectives The geographical disparity in the access to essential obstetric services is a public health issue in many countries. We explored the association between timely access to obstetric services and the individual risk of adverse birth outcomes. Design Repeated cross-sectional design. Setting South Korean national birth data linked with a medical service provision database. Participants 1 842 718 singleton livebirths from 2014 to 2018. Primary outcome measures Preterm birth (PTB), post-term birth, low birth weight (LBW) and macrosomia. Results In the study population, 9.3% of mothers lived in districts where the Time Relevance Index (TRI) was as low as the first quartile (40.6%). Overall PTB and post-term birth rates were 5.0% and 0.1%, respectively. Among term livebirths, LBW and macrosomia occurred in 1.0% and 3.3%, respectively. When the TRI is lower, representing less access to obstetric care, the risk of macrosomia was higher (adjusted OR=1.15, 95% CI 1.11 to 1.20 for Q1 compared with Q4). Similarly, PTB is more likely to occur when TRI is lower (1.05, 95% CI 1.00 to 1.10 for Q1; 1.03, 95% CI 1.01 to 1.05 for Q2). There were some inverse associations between TRI and post-term birth (0.80, 95% CI 0.71 to 0.91, for Q2; 0.84, 95% CI 0.76 to 0.93, for Q3). Conclusions We observed less accessibility to obstetric service is associated with higher risks of macrosomia and PTB. This finding supports the role of obstetric service accessibility in the individual risk of adverse birth outcomes.
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The Child Behavior Checklist for Ages 6–18 (CBCL/6-18) possesses newly developed DSM-Oriented Scales, constructed through expert clinical judgment to match selected categories for behavioral/emotional problems as described in the DSM-IV. The present investigation examined the basic psychometric properties for all six DSM-Oriented Scales (i.e., Affective, Anxiety, Somatic, Attention-Deficit/Hyperactivity, Oppositional, and Conduct Scales) in a large clinical sample of children and adolescents (N = 673). Findings from the present study provide strong evidence for the reliability, as well as convergent and discriminative validity, of these scales. It appears that the DSM-Oriented Scales may provide accurate supplementary information that may be considered when formulating clinical diagnoses.
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Unlabelled: Neonatal encephalopathy (NE) following perinatal asphyxia (PA) is considered an important cause of later neurodevelopmental impairment in infants born at term. This review discusses long-term consequences for general cognitive functioning, educational achievement, neuropsychological functioning and behavior. In all areas reviewed, the outcome of children with mild NE is consistently positive and the outcome of children with severe NE consistently negative. However, children with moderate NE form a more heterogeneous group with respect to outcome. On average, intelligence scores are below those of children with mild NE and age-matched peers, but within the normal range. With respect to educational achievement, difficulties have been found in the domains reading, spelling and arithmetic/mathematics. So far, studies of neuropsychological functioning have yielded ambiguous results in children with moderate NE. A few studies suggest elevated rates of hyperactivity in children with moderate NE and autism in children with moderate and severe NE. Conclusion: Behavioral monitoring is required for all children with NE. In addition, systematic, detailed neuropsychological examination is needed especially for children with moderate NE.
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The timely onset of labor and birth is an important determinant of perinatal outcome. Prolonged (postterm) pregnancy—defined as delivery at or beyond 42 weeks' gestation—complicates 10% of all gestations and is associated with increased risks to both fetus (stillbirth, macrosomia, birth injury, meconium aspiration syndrome) and mother (cesarean delivery, severe perineal injury, postpartum hemorrhage). The risk of routine induction of labor (failed induction leading to cesarean delivery) in the era of cervical ripening is lower than previously reported. For these reasons, the authors favor a policy of routine induction of labor for low-risk pregnancies at 41 weeks' gestation.
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discusses why theories and views based on adult [brain] lesion effects or on symptoms (behavioral and biological) so frequently fail to account for the brain bases of developmental disorders / [suggests that] the fetal brain differs greatly from the adult brain, and symptoms, which are end products of development, can be far removed from beginning causes / erroneous is the notion that if the most critical or pathognomonic behavioral or biological symptoms of a developmental disorder could be identified, then one should necessarily be able to travel backward from them to root causes / the history of research on developmental disorders (e.g., autism, dyslexia, schizophrenia, and so on) is replete with examples of dead ends resulting from this simplistic approach / because of the special nature of neurodevelopmental processes, particular problems are encountered when seeking the precipitating perturbations underlying developmental disorders the traditional approach in research on developmental psychopathologies / principles governing normal and abnormal neurodevelopment / the neurodevelopmental approach: considerations (PsycINFO Database Record (c) 2012 APA, all rights reserved)
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About 5% of babies are born postterm (that is, delivered after 42 completed weeks of gestation). Postterm infants experience more morbidity and mortality than term infants, prompting routine (and expensive) antenatal testing and active management of postterm pregnancies. This article reviews the epidemiology of postterm delivery. A few congenital conditions associated with disruption of the fetal-pituitary-adrenal axis as well as a rare maternal enzyme deficiency have long been identified with postterm delivery. In recent literature, environmental pollution, diet, and pharmaceutical agents have been associated with postterm birth. Very little systematic research has focused on identifying risk factors for this poorly understood birth outcome.
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To investigate risk factors associated with postterm pregnancy and cesarean delivery following labor induction. Population-based cohort study. Sweden. From the Swedish Medical Birth Register, a total of 1,176,131 singletons births from gestational week 37 and onwards, between 1992 and 2006. Unconditional logistic regression analysis. Risk of postterm pregnancy (delivery at >or=42 weeks) and cesarean delivery following labor induction. Among 1,176,131 births, 8.94% were delivered postterm. Compared to normal weight women, the risk of postterm pregnancy in obese women was almost doubled (adjusted OR: 1.63, 95% CI 1.59-1.67). The risk of postterm pregnancy increased with increasing maternal age and was higher among primiparous women. The risk of cesarean section (CS) following labor induction postterm, increased with maternal age and BMI, and was more than doubled among women 35 years and older (adjusted OR 2.28, 95% CI 2.04-2.56). A fivefold risk of CS was seen among nulliparous women (adjusted OR 5.05, 95% CI 4.71-5.42). Parous women with a previous CS undergoing labor induction had a sevenfold increased risk of CS postterm (adjusted OR 7.19, 95% CI 5.93-8.71). Nulliparity, advanced maternal age and obesity were the strongest risk factors for postterm pregnancy and CS following labor induction in postterm pregnancy. Including maternal risk factors to the cervical assessment may improve prediction of vaginal delivery following labor induction in postterm pregnancy.