Prevalence and perinatal mortality associated with preterm births in a tertiary medical center in South East Nigeria

Abstract

Background: Preterm birth is a high risk condition associated with significant mortality and morbidity in the perinatal, neonatal, and childhood periods, and even in adulthood. Knowledge of the epidemiology of preterm births is necessary for planning appropriate maternal and fetal care.
Objective: The objective of this study was to determine the prevalence, pattern, and perinatal mortality associated with preterm births at the University of Nigeria Teaching Hospital, Enugu, South East Nigeria.
Methods: This was a review of prospectively collected routine delivery data involving preterm deliveries that occurred between 1 January 2009 and 31 December 2013. Data analysis involved descriptive and inferential statistics at 95% level of confidence using SPSS version 17.0 for Windows.
Results: There were 3,760 live births over the 5-year study period out of which 636 were preterm births, giving a prevalence rate of 16.9%. Spontaneous preterm births occurred in approximately 57% of preterm births while provider-initiated births occurred in 43%. The mean gestational age at preterm deliveries was 32.6±3.2 weeks while the mean birth weight was 2.0±0.8 kilograms. Approximately 89% of preterm births involved singleton pregnancies. Sixty-eight percent of preterm births were moderate to late preterm. The male:female ratio of preterm babies born during the period was 1.2:1. The adjusted perinatal mortality rate for preterm babies in the study center was 46.1% (236/512). The stillbirth rate for preterm babies was 22.0% (149/678) and the adjusted early neonatal death rate was 24.0% (87/363).
Conclusion: The prevalence of preterm births and associated perinatal mortality were high which may be a reflection of suboptimal prenatal and newborn care. An urgent improvement in prenatal and newborn care is therefore needed in the study center in order to improve the capacity to prevent or abate preterm labor, and preterm premature rupture of membranes; and to reduce avoidable stillbirths. Further upgrading of personnel and facilities in the newborn special care unit is also required to minimize early neonatal deaths.

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Open Access Full Text Article
http://dx.doi.org/10.2147/IJWH.S72229
Prevalence and perinatal mortality associated
with preterm births in a tertiary medical
center in South East Nigeria
Chukwuemeka Anthony
Iyoke1
Osaheni Lucky Lawani2
Euzebus Chinonye Ezugwu1
Gideon Ilechukwu3
Peter Onubiwe Nkwo1
Sunday Gabriel Mba1
Isaac Nwabueze Asinobi4
1Department of Obstetrics and
Gynaecology, University of Nigeria
Teaching Hospital, Ituku-Ozalla,
Enugu, Nigeria; 2Department of
Obs tetrics and Gynaecology, Fede ral
Teaching Hospital, Abakaliki, Nigeria;
3Department of Paediatrics, Whiston
Hospital, St Helen’s and Knowsley
Teaching Hospitals NHS Trust,
Prescot, Lancashire, UK; 4Department
of Paediatrics, University of Nigeria
Teaching Hospital, Ituku-Ozalla, Enugu,
Nigeria
Correspondence: Chukwuemeka
Anthony Iyoke
Department of Obstetrics and
Gynaecology, University of Nigeria
Teaching Hospital, PO Box 4994, Enugu,
400001, Nigeria
Tel +234 80 8583 1167
Email caiyoke@yahoo.co.uk
Background: Preterm birth is a high risk condition associated with significant mortality and
morbidity in the perinatal, neonatal, and childhood periods, and even in adulthood. Knowledge
of the epidemiology of preterm births is necessary for planning appropriate maternal and fetal
care.
Objective: The objective of this study was to determine the prevalence, pattern, and perinatal
mortality associated with preterm births at the University of Nigeria Teaching Hospital, Enugu,
South East Nigeria.
Methods: This was a review of prospectively collected routine delivery data involving preterm
deliveries that occurred between 1 January 2009 and 31 December 2013. Data analysis involved
descriptive and inferential statistics at 95% level of confidence using SPSS version 17.0 for
Windows.
Results: There were 3,760 live births over the 5-year study period out of which 636 were preterm
births, giving a prevalence rate of 16.9%. Spontaneous preterm births occurred in approximately
57% of preterm births while provider-initiated births occurred in 43%. The mean gestational age
at preterm deliveries was 32.6±3.2 weeks while the mean birth weight was 2.0±0.8 kilograms.
Approximately 89% of preterm births involved singleton pregnancies. Sixty-eight percent of
preterm births were moderate to late preterm. The male:female ratio of preterm babies born
during the period was 1.2:1. The adjusted perinatal mortality rate for preterm babies in the study
center was 46.1% (236/512). The stillbirth rate for preterm babies was 22.0% (149/678) and the
adjusted early neonatal death rate was 24.0% (87/363).
Conclusion: The prevalence of preterm births and associated perinatal mortality were high
which may be a reflection of suboptimal prenatal and newborn care. An urgent improvement
in prenatal and newborn care is therefore needed in the study center in order to improve the
capacity to prevent or abate preterm labor, and preterm premature rupture of membranes; and
to reduce avoidable stillbirths. Further upgrading of personnel and facilities in the newborn
special care unit is also required to minimize early neonatal deaths.
Keywords: preterm birth, prevalence, mortality, pattern, Nigeria
Introduction
Globally, preterm birth is a major clinical problem associated with significant mortality
and morbidity in the perinatal, neonatal, and childhood periods and even in adulthood.1–5
It is a major cause of long-term loss of human potential among survivors.6 In fact, the
global concern about the burden of preterm birth has resulted in November 7th being
earmarked as World Prematurity Day.7 Increasing preterm birth could significantly
militate against the achievement of Millennium Development Goal 4.8 Perhaps in
response to this threat, a goal to reduce preterm-specific mortality by 50% by 2025 has
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Iyoke et al
been set in the World Health Organization’s (WHO) “Born
Too Soon” report.6
Preterm birth has been defined by WHO as any live
birth before 37 completed weeks of gestation or fewer than
259 days since the first day of a woman’s last menstrual
period.3,6,9 The point in pregnancy when the delivery of a
fetus is counted as birth rather than abortion differs across
countries.3 It depends on the perceived fetal age of viability,
which is based on the availability of modern neonatal care
facilities and expertise.10 In developing countries like Nigeria,
the legal fetal age of viability is 28 weeks.8 However, below
this gestational age, births involving babies with signs of life
after 22 weeks are also taken as deliveries.
Preterm births have been categorized based on clini-
cal presentation into: spontaneous preterm births (which
comprise those following spontaneous preterm labor with
or without preterm premature rupture of membranes)
and provider-initiated preterm births.5,6 Globally, about
15 million babies are born preterm annually, representing
11.1% of all live births.5,6,11,12 However, the preterm birth
rate varies from one place to another depending inter
alia on the method of gestational age assessment and the
perceived fetal age of viability.3,9 However, it has been
reported to be increasing globally.3,9,13–15 South Asia and
sub-Saharan Africa are the regions responsible for 60%
of global preterm births.6,16 Reports from some African
countries have shown overall preterm birth rate ranging
from 11.1% to 57%.4,12
Improved care of preterm babies has resulted in reduced
mortality in developed countries.2,11 This is not so in develop-
ing countries where the management of preterm birth babies
is fraught with difficulties arising from scarcity of resources
typified by poorly-equipped specialized newborn care units.12
Consequently, the burden of the complications and mortality
from preterm births remains a significant potential challenge to
newborn health in resource-poor settings like ours. Currently,
there is scant literature on the epidemiology of preterm births
in South East Nigeria to guide efforts at preventing and/
or managing preterm births. The aims of this study were to
determine the prevalence and pattern of, and perinatal mortal-
ity associated with preterm births at the University of Nigeria
Teaching Hospital, Enugu, South East Nigeria.
Methods
Study center
The study was carried out at the University of Nigeria Teaching
Hospital (UNTH), Enugu. There are ten clinical departments in
UNTH, two of which are Obstetrics/Gynaecology department
and Paediatrics department. The Paediatrics department has a
specialized neonatology unit, the Newborn Special Care Unit
(NBSCU), which is a neonatal intensive care unit located within
the labor ward complex. The two departments render 24-hour
obstetric and neonatal services. UNTH serves as a referral
hospital to other health facilities mainly within Enugu State and
less from the neighboring states of Abia, Ebonyi, Anambra, and
Imo. Consequently, the maternity and neonatology units of the
UNTH also receive pregnant women and/or newborn babies
from across Enugu and the neighboring states.
Study design
This was a retrospective review of prospectively collected
routine delivery data on preterm births.
Study period
The study covered the period between 1 January 2009 and
31 December 2013.
Sampling
The delivery database of the UNTH was reviewed and all
births that occurred between 2009 and 2013 were exam-
ined. All women who delivered between gestational ages
28 weeks and 36 weeks plus 6 days whose records were
available were selected. In addition, those who delivered
babies below 28 weeks old whose babies had signs of life
during study period were also included. The delivery and
case records of selected patients were retrieved for data
collection. The women were included if the date of the last
menstrual period was reliably documented and/or there was
ultrasound confirmation of gestational age. Similarly, the
NBSCU database was reviewed and all the preterm babies
who were delivered at the UNTH were identified and their
case records were retrieved.
Data collection
Data extraction was done by two of the authors (CAI and INA)
and two other trained research assistants who were of the rank
of registrars (one each from the departments of Obstetrics/
Gynaecology and Paediatrics). The data were abstracted from
the delivery database, mothers’ clinical case notes, NBSCU
database, and the babies’ case notes. Data abstracted included
maternal age, booking status, parity, educational status, occu-
pation, previous gynecological and obstetric history, antenatal
history, intrapartum events, gestational age at delivery, first-
and fifth-minute Apgar scores, fetal sex, NBSCU admission,
perinatal complications, and causes of perinatal deaths. The
information extracted was entered into a structured pro forma

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Prevalence and perinatal mortality associated with preterm births
which was divided into sections which included maternal socio-
demographic data, obstetric history, prenatal interventions/
treatment, intrapartum findings, and neonatal outcome.
Data analysis
The statistical analysis was carried out using Statistical
Package for Social Sciences (SPSS) version 17.0 for Windows
(SPSS Inc., Chicago, IL, USA) and Microsoft Excel software
(Microsoft Corporation, Redmond, WA, USA). Classifications
of preterm births and low birth weight were based on the WHO
sub-categorization of preterm births and low birth weight.17
Provider-initiated preterm birth was defined as birth due to
elective induction of preterm labor or due to preterm cesarean
section before the onset of labor. Frequencies, means, and pro-
portions of variables were computed. The association between
categorical variables was determined using chi-square test
or Fisher’s exact test where appropriate. For the estimation
of perinatal mortality rate and early neonatal mortality rate,
only the records of babies admitted into the NBSCU could be
accessed and were therefore used: mortality data on preterm
babies who were not admitted into the NBSCU were not
available. Adjusted perinatal and early neonatal mortality
rates were therefore computed.
To determine the variables that predicted perinatal death,
a bivariate logistic regression analysis was done. Only vari-
ables significantly associated with perinatal death on bivariate
analysis were included in logistic regression models. The
Hosmer–Lemeshow goodness-of-fit test was done to deter-
mine the fitness of the data to the logistic regression model.
The results were reported as adjusted odds ratios and 95%
confidence intervals. For all analyses, P-value #0.05 was
considered significant.
Ethical consideration
Ethical approval for the study was obtained from the
Research Ethics Committee of the UNTH.
Results
Prevalence of preterm births
There were 3,760 live births over the 5-year study period out
of which 636 involved preterm deliveries giving a preterm
birth rate of 16.9% (169 preterm births per 1,000 live births).
The records of 592 preterm births were available and were
analyzed. Overall, spontaneous preterm births occurred in
approximately 57% of preterm births while provider- initiated
births occurred in 43%. Preterm premature rupture of mem-
branes preceded delivery in 15.2% (91/592) of preterm births.
Table 1 shows the yearly distribution of preterm births.
The preterm birth rate increased from 9.8% in 2009 to 17.1%
in 2013 after peaking at 23% in 2012. Figure 1 is a line graph
to illustrate the trends in the preterm birth rates while Figure 2
is a stacked bar chart showing the trend in the proportion of
preterm births due to provider-initiated births. The proportion
of preterm births due to provider-initiated births increased
about 4-fold between 2009 and 2013.
Pattern of preterm births
Table 2 shows the characteristics of women who had pre-
term deliveries. The mean age of mothers of preterm babies
was 30.3±5.3 years and mean parity was 2.6±1.8. The
mean postpartum blood loss was 363.1±279.1 mL (range
50–2,000 mL).
Table 3 summarizes the characteristics of preterm babies.
The mean gestational age at preterm deliveries was 32.6±3.2
weeks while the mean birth weight was 2.0±0.8 kilograms.
Approximately 89% of preterm births involved singleton
pregnancies and 68% of preterm births were moderate to late
preterm occurring from 32 weeks gestational age to 36 weeks,
6 days. The male:female ratio of preterm babies born during
the period was 1.2:1. Approximately 69% of preterm babies
had either low birth weight, very low birth weight, or extreme
low birth weight. The distribution of the birth weights of pre-
term babies based on gestational age is shown in Table 4.
2009
Percentage
0
5
10
15
20
Incidence
25
2010 2012 20132011
Figure 1 Trend in the prevalence of preterm births at University of Nigeria Teaching
Hospital, Enugu, 2009–2013.
Table 1 Yearly distribution of births at the University of Nigeria
Teaching Hospital, Enugu, from 2009–2013
Year Total
births
Preterm
births
Term/post
term deliveries
Prevalence
of preterm
births, %
2009 468 46 422 9.8
2010 528 83 445 15.7
2011 826 112 714 13.6
2012 984 232 752 23.7
2013 954 163 791 17.1
Total 3,760 636 3,124 16.9

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Iyoke et al
2009
0
5
10
15
20
Spontaneous
Provider-initiated
25
2010 2011
Percentage
2012 2013
Figure 2 Trend in the proportion of preterm births due to provider-initiated
births among preterm births at the University of Nigeria Teaching Hospital, Enugu,
2009–2013.
Table 2 Characteristics of women who delivered premature babies from 2009–2013 at the University of Nigeria Teaching Hospital, Enugu
Characteristic Subgroups Frequency Percentage
Age (n=592) ,20 years
20–29 years
30–39 years
40–49 years
50–59 years
14
248
308
20
2
2.4
41.9
52.0
3.4
0.3
Occupation (n=580) Unemployed/housewife
Trader/businesswoman
Civil servant/teacher
Professional
85
129
312
54
14.7
22.2
53.8
9.3
Educational status (n=572) No formal education
Primary school certicate holder
Secondary school certicate holder
Diploma/degree holder or higher
8
41
222
301
1.4
7.2
38.8
52.6
Religion (n=562) Christianity
Catholic
Anglican
Pentecostal
Others
Islam
552
228
156
144
24
10
98.2
42.3
27.8
25.6
4.3
1.8
Parity (n=592) 0 (nulliparous)
1 (primiparous)
2–4 (multiparous)
$5 (grand multiparous)
108
294
188
2
18.2
49.7
31.8
0.3
Booking status (n=592) Booked
Unbooked
320
272
54.0
46.0
Perinatal mortality associated
with preterm births
There were 149 stillbirths during the study period while 87
early neonatal deaths occurred among 363 preterm babies
admitted to the NBSCU. The adjusted perinatal mortality
rate was 46.1% (236/512) of total births.
Stillbirths
The stillbirth rate for preterm deliveries was 22.0% (149/678)
of total births. Fresh stillbirth occurred in 86% (128/149)
of stillbirths. Approximately 26% of singleton deliveries
were still-born compared to 22% of twins. Table 5 shows
the distribution of stillbirths according to gestational ages.
There were no stillbirths among triplets and quadruplet
preterm births. Table 6 shows a bivariate analysis of socio-
demographic factors associated with stillbirth. Year of study,
gestational age group, birth weight group, mode of delivery,
and appropriateness of weight in relation to gestational age
were all significantly associated with preterm stillbirths.
Table 7 summarizes the logistic regression model to deter-
mine factors that predicted preterm stillbirths. Only route of
delivery and gestational age group had significant predictive
effect. Compared to babies born between 32–36+6 weeks,
babies born between 28–31+6 weeks were two-and-a-half
times more likely to be stillborn, while babies born at less
than 28 weeks were three times more likely to be stillborn.
Similarly, compared to those born by cesarean section, those
born vaginally were six times more likely to be stillborn.
Early neonatal deaths
The early neonatal mortality rate for preterm babies born at
the UNTH who were admitted to the NBSCU during the study
period was 24.0% (87/363), and this excludes early neonatal
mortality among preterm babies who were not admitted into
the NBSCU. Table 8 shows the prevalence of early neonatal

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Prevalence and perinatal mortality associated with preterm births
Table 4 Distribution of birth weights of premature babies according to gestational age of birth at the University of Nigeria Teaching
Hospital, Enugu, from 2009-2013
Gestational age Extreme low birth
weight ,1 kg
Very low birth
weight 1–1.49 kg
Low birth
weight 1.5–2.49 kg
Normal birth
weight 2.5–3.9 kg
Large birth
weight 4 kg
or more
Total
Extreme preterm
,28 weeks (%)
19 (55.9) 12 (35.3) 2 (5.9) 1 (2.9) 0 (0) 34 (100)
Very preterm
28–31 weeks 6 days (%)
22 (14.4) 65 (42.5) 56 (36.6) 10 (6.5) 0 (0) 153 (100)
Moderate or late preterm
32–36 weeks 6 days (%)
6 (1.3) 23 (5.7) 205 (50.6) 167 (41.2) 5 (1.2) 405 (100)
Total (%) 47 (7.8) 100 (16.9) 263 (44.4) 178 (30.1) 5 (0.8) 592 (100)
Table 3 Characteristics of preterm babies born at the University
of Nigeria Teaching Hospital, Enugu, from 2009-2013
Feature Subgroups Frequency
n=592
Percentage
Gestational
type
Singleton
Twin
Triplet
Quadruplet
529
55
6
2
89.4
9.3
1.0
0.3
Route of
delivery
Vaginal
Cesarean
340
252
57.4
42.6
Type of
preterm
birth
Extreme preterm
(,28 weeks)
Very preterm
(28–,32 weeks)
Moderate to late
preterm
(32–,37 weeks)
35
153
405
5.9
25.8
68.3
Birth weight
group
Extreme low birth
weight (,1 kg)
Very low birth
weight (1–,1.5 kg)
Low birth weight
(1.5–2.4 kg)
Normal birth weight
(2.5–3.9 kg)
Large birth weight
(4 kg or more)
47
100
263
178
5
7.9
16.9
44.4
30.0
0.8
Fetal sex Male
Female
319
273
53.9
46.1
Apgar score 1–5
6–7
8–10
25
66
347
4.2
11.1
58.6
Newborn
intensive care
admission
Yes
No
363
229
61.3
38.7
deaths among preterm babies during the study period.
Approximately 86% (12/14) of liveborn extremely preterm
babies died in the early neonatal period compared to 50.5%
of very preterm babies (48/95). Table 9 shows the common-
est complications of prematurity across the years of study.
Jaundice (58.1%), sepsis (50.4%), and respiratory difficulties
(43.0%) were the commonest complications of preterm births
among preterm babies admitted to the NBSCU.
Discussion
A hospital-based maternity review of preterm deliveries was
an appropriate study design to determine the prevalence and
trend of preterm births and perinatal deaths: a population-
based register of preterm births and stillbirths does not exist
in our area. Studies based on admissions to newborn intensive
care units would have excluded stillbirths and preterm births
that did not require intensive care admissions: estimates from
such studies would hardly be representative of all preterm
births. In another vein, among the few maternity-based
studies on preterm births in Nigeria, most addressed determi-
nants of preterm births: we found no study which evaluated
perinatal mortality associated with preterm births.18–21 This
is the first study on the perinatal mortality associated with
preterm births in this city.
Our study showed that the prevalence of preterm births
during the study period was higher than the 12% reported by
Mokuolu et al at Ilorin, Nigeria19 and the 8.5% reported by
Etuk et al from Calabar, Nigeria.21 It is also higher than the
less than 15% national preterm birth rate estimated by the
WHO for Nigeria in the “Born Too Soon” report.6 The higher
incidence rate recorded in this study compared to the two
hospital-based studies from other parts of Nigeria may be due
to differences in study design. Despite the fact that these stud-
ies were also based on maternity ward deliveries, the study
in Calabar focused on factors influencing the incidence of
preterm births and detailed characterization of preterm births
was not given: it was therefore difficult to determine whether
the study included multiple births. The study by Mokuolu
et al19 was a prospective study of a very short duration of 9
months: it was also not reported whether multiple pregnancies
were included or not. The discrepancy between our report
and the WHO quoted national prevalence of preterm births

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Iyoke et al
Table 5 Distribution of stillbirths based on gestational age
Stillbirths ,28 weeks
(%)
28-32+6 weeks
(%)
32-36+6 weeks
(%)
Yes 14 (41.2) 95 (62.1) 334 (82.5)
No 20 (58.8) 58 (38.9) 71 (17.5)
Total 34 (100) 153 (100) 405 (100)
Note: +6represents +6 days.
Table 6 Association of preterm stillbirth with maternal-fetal
characteristics among preterm deliveries at University of Nigeria
Teaching Hospital, Enugu, 2009–2013
Variable Stillbirth P-value
Yes No
Year of delivery
2009
2010
2011
2012
2013
43
14
32
17
31
67
69
80
59
115
0.003*
Gestational age at delivery
,28 weeks
28–,32
32–,37
20
58
71
14
95
334
,0.001*
Booking status of mother
Booked
Unbooked
72
77
249
194
0.10
Delivery mode
Vaginal
Cesarean
127
22
213
230
,0.001*
Birth weight group
Extreme low birth weight
Very low birth weight
Low birth weight
Normal birth weight
Large birth weight
17
58
52
26
0
29
42
211
152
5
,0.001*
Fetal sex
Male
Female
89
60
230
213
0.10
Gestational type
Singleton
Twins
Triplets
Quadruplets
137
12
0
0
392
43
6
2
0.37
Notes: *Statistically signicant.
Table 7 Logistic regression to determine predictors of stillbirth
in preterm babies delivered at the University of Nigeria Teaching
Hospital, Enugu, 2009–2013
Variable B
coefcient
P-value Odds
ratio
95%
condence
interval
Gestational age group
,28 weeks
28–31+6 weeks
32–36+6 weeks
1.19
0.72
0a
0.004*
0.002*
3.28
2.51
1.45, 7.40
1.30, 3.30
Delivery mode
Vaginal
Cesarean
1.77
0a
,0.001*
5.86
3.45, 9.93
Appropriateness of weight for gestational age
Small for
gestational age
Large for
gestational age
Appropriate
for gestational age
0.90
1.75
0a
0.21
0.02*
2.45
5.73
0.60, 10.08
1.35, 23.9
Year
2009
2010
2011
2012
2013
0.27
-0.52
-0.11
-0.52
0a
0.54
0.26
0.79
0.27
-1.3
-0.59
-0.89
-0.60
0.57, 2.98
0.24, 1.48
0.39, 2.04
0.24, 1.48
Notes: aReference predictor variable; *statistically signicant. +6represents +6 days.
Table 8 Prevalence of early neonatal deaths among preterm
babies born at the University of Nigeria Teaching Hospital who
were admitted to the Newborn Special Care Unit (NBSCU) from
2009–2013
Year Number of preterm
babies admitted
to NBSCU
Early
neonatal
deaths
Prevalence
of early neonatal
mortality
2009 61 13 21.3
2010 44 13 29.5
2011 64 24 37.5
2012 47 16 34.0
2013 53 14 26.4
Total 269 80 29.7a
Note: aAverage prevalence.
in Nigeria may be due to the hospital-based nature of this
study, which was likely to reflect referral bias.
This study also found a rising trend in the prevalence
of preterm births during the study period. Although we
found no previous study on the trends in preterm deliver-
ies in Nigeria, the rising trend suggested by this study is
in line with the global trend reported by the WHO on the
incidence of preterm births.17 Besides, although the study
showed rises in both spontaneous and provider-initiated
preterm births, it was striking that there was a much greater
increase in the provider-initiated preterm births. This rise in
provider-initiated preterm births could be a reflection of an
emerging trend in obstetric care in the hospital. The recent
upgrading of the NBSCU of the hospital which resulted
in increased capacity to salvage preterm babies may have
given obstetricians greater confidence in initiating preterm
births as a way of managing obstetric cases with high risk of
intrauterine fetal death.
The high and rising trend in preterm births in this study
contrasts with the pattern in the industrialized world. A recent
report from Europe showed that many countries maintained
or had reduced rates of singleton preterm births over the

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Prevalence and perinatal mortality associated with preterm births
Another finding in this study is the proportion of preterm
babies (6%) born before 28 weeks with signs of life. This
could be one more reason why improvement in newborn
intensive care units is urgently needed to facilitate the sal-
vage of these babies. Besides, with the improvement in the
salvage rate of preterm babies, this finding may indicate
a foreseeable need to lower the legal definition of what
constitutes birth as opposed to miscarriage in Nigeria. This
is because sticking to 28 weeks may no longer be tenable
with increasing birth and survival of babies born before
28 weeks gestational age.
The strengths of this study include the use of comprehen-
sive hospital delivery data, as opposed to newborn admis-
sions only for the determination of the prevalence of preterm
births. The weaknesses include the hospital-based nature of
the study in a country where most deliveries occur outside
of health facilities. This may suggest that the prevalence
rate of preterm deliveries could be substantially different
from the prevalence in the general population. The fact that
complicated obstetric cases are referred to this hospital could
lead to a referral bias leading to over-estimation of preterm
births and deaths.
We conclude that this study found a higher than the
national average in the prevalence of preterm births and
stillbirths, yielding a very high perinatal mortality rate
among preterm births. These may, in part, be a reflection of
suboptimal prenatal and newborn care. An urgent improve-
ment in prenatal and newborn care is therefore needed in
the study center in order to improve the capacity to prevent
or abate preterm labor, and preterm premature rupture of
membranes; and to reduce stillbirths from treatable causes
such as malaria and bacterial infections. Further upgrading
of personnel and facilities in the NBSCU is also required to
minimize early neonatal deaths.
Disclosure
The authors have no conflict of interest in this study.
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Year Number
of preterm
babies
Neonatal
jaundice
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