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Abstract and Figures

Objective To estimate the incidence of incisional hernias requiring surgical repair after cesarean delivery over a 10-year period. Methods This population- and register-based cohort study identified all women in Denmark with no history of previous abdominal surgery who had a cesarean delivery between 1991 and 2000. The cohort was followed from their first until 10 years after their last cesarean delivery within the inclusion period or until the first of the following events: hernia repair, death, emigration, abdominal surgery, or cesarean delivery after the inclusion period. For women who had a hernia repair, hospital records regarding the surgery and previous cesarean deliveries were tracked and manually analyzed to validate the relationship between hernia repair and cesarean delivery. Data were analyzed with a competing risk analysis that included each cesarean delivery. Results We identified 57,564 women who had had 68,271 cesarean deliveries during the inclusion period. During follow-up, 134 of these women had a hernia requiring repair. Of these 68 (51% [95% CI 42–60%]) were in a midline incision although the transverse incision was the primary approach at cesarean delivery during the inclusion period. The cumulated incidence of a hernia repair within 10 years after a cesarean delivery was 0.197% (95% CI 0.164–0.234%). The risk of a hernia repair was higher during the first 3 years after a cesarean delivery, with an incidence after 3 years of 0.157% (95% CI 0.127–0.187%). Conclusions The overall risk of an incisional hernia requiring surgical repair within 10 years after a cesarean delivery was 2 per 1000 deliveries in a population in which the transverse incision was the primary approach at cesarean delivery.
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Incidence of Incisional Hernia after Cesarean Delivery: A
Register-Based Cohort Study
Anna J. M. Aabakke
1
*, Lone Krebs
1
, Steen Ladelund
2
, Niels J. Secher
3,4
1Department of Obstetrics and Gynecology, University of Copenhagen, Holbæk Hospital, Holbæk, Denmark, 2Clinical Research Center, University of Copenhagen,
Hvidovre Hospital, Hvidovre, Denmark, 3The Research Unit Women’s and Children’s Health, The Juliane Marie Center, Copenhagen University Hospital, Copenhagen,
Denmark, 4Department of Obstetrics and Gynecology, Aarhus University Hospital, Aarhus, Denmark
Abstract
Objective:
To estimate the incidence of incisional hernias requiring surgical repair after cesarean delivery over a 10-year
period.
Methods:
This population- and register-based cohort study identified all women in Denmark with no history of previous
abdominal surgery who had a cesarean delivery between 1991 and 2000. The cohort was followed from their first until 10
years after their last cesarean delivery within the inclusion period or until the first of the following events: hernia repair,
death, emigration, abdominal surgery, or cesarean delivery after the inclusion period. For women who had a hernia repair,
hospital records regarding the surgery and previous cesarean deliveries were tracked and manually analyzed to validate the
relationship between hernia repair and cesarean delivery. Data were analyzed with a competing risk analysis that included
each cesarean delivery.
Results:
We identified 57,564 women who had had 68,271 cesarean deliveries during the inclusion period. During follow-up,
134 of these women had a hernia requiring repair. Of these 68 (51% [95% CI 42–60%]) were in a midline incision although
the transverse incision was the primary approach at cesarean delivery during the inclusion period. The cumulated incidence
of a hernia repair within 10 years after a cesarean delivery was 0.197% (95% CI 0.164–0.234%). The risk of a hernia repair was
higher during the first 3 years after a cesarean delivery, with an incidence after 3 years of 0.157% (95% CI 0.127–0.187%).
Conclusions:
The overall risk of an incisional hernia requiring surgical repair within 10 years after a cesarean delivery was 2
per 1000 deliveries in a population in which the transverse incision was the primary approach at cesarean delivery.
Citation: Aabakke AJM, Krebs L, Ladelund S, Secher NJ (2014) Incidence of Incisional Hernia after Cesarean Delivery: A Register-Based Cohort Study. PLoS
ONE 9(9): e108829. doi:10.1371/journal.pone.0108829
Editor: Katariina Laine, Oslo University Hospital, Ulleva
˚l, Norway
Received April 28, 2014; Accepted June 13, 2014; Published September 30, 2014
Copyright: ß2014 Aabakke et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: This work was supported by grants from the Faculty of Health, University of Copenhagen (www.sund.ku.dk), The Region Zealand Health Sciences
Research Foundation (http://www.regionsjaelland.dk/sundhed/forskning/praktisk%20om%20forskning/sider/den-regionale-forskningsfond.aspx), and Depart-
ment of Obstetrics and Gynecology, University of Copenhagen, Holbæk Hospital. The funders had no role in study design, data collection and analysis, decision to
publish, or preparation of the manuscript.
Competing Interests: The authors have declared that no competing interests exist.
* Email: aabakke@gmail.com
Introduction
Cesarean delivery is the most common surgical procedure in the
United States, and the rates are increasing worldwide [1,2]. In the
United States, Latin America, Australia, and several European
countries cesarean delivery rates are presently above 30% [3–6].
Several studies have found both short- and long-term complica-
tions related to cesarean delivery [7–11]. Incisional hernia is a
well-known long-term complication of abdominal surgery, with a
reported incidence of 3.0–20.6% in association with midline
incisions and 0–2.1% with lower transverse incisions [12–19]. Two
meta-analyses have confirmed that the risk of developing an
incisional hernia after abdominal surgery is higher after a midline
than a transverse incision [20,21]. However, only one study, with 6
to 12 months follow-up, has focused on incisional hernia after
cesarean delivery [12]. The authors found no incisional hernias
after 280 cesarean deliveries performed through a transverse
incision. Studies have found that more than 50% of incisional
hernias occur more than 1 year after surgery, indicating that the
incidence of incisional hernia after cesarean delivery might be
underreported [16,22].
The objective of this study was to estimate the incidence of
incisional hernias requiring surgical repair after cesarean delivery
in a large cohort during a 10-year period.
Materials and Methods
This was a population-based cohort study with data obtained
from the Danish National Patient Register and the Danish
Medical Birth Register.
In Denmark all in- and out-patient hospital contacts are
registered in the Danish National Patient Register established in
1977 and all births in the Danish Medical Birth Register
established in 1968 [23,24]. Both registers were administered by
the Danish National Board of Health at the time of data
extraction. All Danish citizens have a unique personal identifica-
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tion number, and information in the registers is linked to this
number. The registers contain information on age, gender,
surgical procedure, diagnosis, readmission, and reoperation, but
no surgical details (e.g. type of incision and suture material).
Surgical procedures have since 1996 been recorded based on
codes according to the NOMESCO classification of surgical
procedures (a common Nordic classification) [25]. Before 1996,
surgical registrations were based on a national classification of
treatments and surgical procedures. The completeness of the
registration in the Danish National Patient Register is 98–100%,
and the validity of the system in terms of the type of surgical
procedure has been proven to be high [26–28].
This study was based on a search in the two registries. The main
inclusion criterion was a cesarean delivery between January 1,
1991 and December 31, 2000 in women with no history of
previous abdominal surgery. Women who had had a cesarean
delivery during the inclusion period were identified through the
codes for cesarean delivery (sectio_u and, sectio_f [1991–95], and
KMCA 10, 11, 12a, 12b [1996–2000]). The cohort was followed
from their first cesarean delivery until 10 years after their last
cesarean delivery in the inclusion period for an event of hernia
repair. Hernia repairs performed during 1991–95 were identified
by the codes herniotomia incisionalis (40680), herniotomia
ventralis (42400), herniotomia parietis abdominis (40600), hernio-
plastica cum implantation (40800), hernioplastica cum implanta-
tione laparascopica (40801), and herniotomia (40740, 42900, and
no previous diagnosis of inguinal hernia). Hernia repairs during
1996–2000 were identified by the code for surgeries of incisional
hernia (KJAD). We registered only the primary hernia repair, and
any recurrences were not included. We also registered events of
death, emigration, abdominal surgery, and cesarean deliveries
during the follow-up period. The surgical codes for hernia repair
do not contain information about the anatomical location of the
hernia. Therefore, for women with a hernia repair, hospital
records of the primary examination, description of surgery, and
discharge letter were retrieved as were the descriptions of the
previous cesarean deliveries. The records were manually analyzed
by two investigators (AA and LK) to validate the relationship
between hernia repair and cesarean delivery and to determine the
type of incision. When in doubt, consensus was obtained through
discussion. Before study initiation, the following exclusion criteria
for the hernia repairs were defined: Diastasis recti without hernia,
hernia not in the cesarean incision, and no hernia. Cases in which
no validation information was accessible were maintained in the
cohort as confirmed cases so that the incidence of hernia repair
was not falsely underestimated.
Ethics Statement
The results of the study were reported following the STROBE
recommendations for strengthening the reporting of observational
studies in epidemiology [29].
The study was approved by the Danish Data Protection Agency
(reg. no. 2013-41-2155). Ethical approval was not required.
Written informed consent was not required and therefore not
obtained for the clinical records to be used in the study. However,
patient records and the data-set were anonymized before analysis.
Statistics
The cumulative risk of a hernia repair after cesarean delivery
was estimated by a competing risk analysis [30]. Each cesarean
delivery during the inclusion period was analyzed individually.
The competing endpoints that mutually excluded each other were
hernia repair, death, abdominal surgery, and a consecutive
cesarean delivery. Emigration during the follow-up period caused
censoring. Right censoring also occurred after 10 years if the
woman did not meet any of the endpoints mentioned above.
Continuous data were analyzed by unpaired ttest when
normally distributed and by Mann Whitney test when not.
Nominal data were analyzed by chi
2
test or, when relevant,
Fischer’s exact test. Pvalues ,0.05 were regarded as statistically
significant.
The analyses were performed using R 3.0.2 (R Foundation for
Statistical Computing, Vienna, Austria) with the add-on library
cmprsk [30], and IBM SPSS Statistics 21 (SPSS Inc., Chicago, IL,
USA).
Results
Between January 1991 and December 2000, 57,564 unique
women, with no history of previous abdominal surgery, had a total
of 68,271 cesarean deliveries. Of these, 158 were identified as
having a subsequent hernia repair performed within 10 years after
their cesarean delivery within the inclusion period. Analysis of the
hospital records excluded 24 cases. Of these, 4 women had a
history of previous abdominal surgery, 4 had abdominal surgery
after the cesarean delivery but before the hernia repair, one had
the hernia repair done coincidently with the including cesarean
delivery, 9 hernias were not in the cesarean incision, 5 had
diastasis recti without hernia, and 1 had no hernia. A total of 134
cases of hernia repair were included in the analysis. In 20 patients,
hospital records from the hernia repair surgery were not available,
primarily due to destruction of medical records after 10 years of
inactivity. In 68 cases (51% [95% CI 42–59%]) the hernias treated
were in a midline incision, in 50 cases (37% [95% CI 29–46%]) in
a transverse incision, and in 16 cases (12% [95% CI 7–19%]) in an
incision of unknown type due to missing cesarean delivery records.
Study design and flow including information on competing events
are illustrated in Figure 1. The basic characteristics of the hernia
repairs based on type of incision did not differ and are shown in
Table 1. There was no change over time in either the frequency of
cesarean deliveries resulting in hernia repairs or the distribution of
transverse and midline incisions among the hernias requiring
hernia repair (data not shown).
The cumulated incidence of a hernia repair within 10 years
after a cesarean delivery was 0.197% (95% CI 0.164–0.234%)
(Figure 2). The risk of a hernia repair was higher within the first 3
years after a cesarean delivery, with a cumulated incidence at 3
years of 0.157% (95% CI 0.127–0.187%) (Figure 2 and Table 2).
Among women who developed an incisional hernia requiring
surgical repair the median time from cesarean delivery to repair
was 1.36 years (IQR 0.79–2.27 years).
Discussion
This prospective cohort study found a cumulated risk of 0.197%
of developing an incisional hernia requiring surgical repair within
10 years after a cesarean delivery. The risk of a hernia repair was
higher during the first 3 years after a cesarean delivery.
Less than half of the hernia repairs were performed within the
first year after the cesarean delivery (Table 2). Our study thereby
confirms previous studies showing that less than half of incisional
hernias develop within the first year after surgery [22]. However, it
cannot be ruled out that women who developed an incisional
hernia within the first year after a cesarean delivery postponed
repair of various reasons.
Through validation, we found that the repairs identified in this
study were of hernias in both midline and transverse incisions and
that more than half of them were of hernias in midline incisions.
During the study period, the majority of cesarean deliveries in
Incisional Hernia after Cesarean Delivery
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Denmark were performed through a transverse incision, but,
unfortunately, the distribution of the two types of incisions during
the study period is unknown. We therefore can only try to make an
estimate of the risk of surgical repair of a hernia in transverse
incisions based on previously published data: In order not to
underestimate the risk, unknown incision types are assumed to be
transverse and the following assumptions regarding midline
incisions are made. The lowest found incidence of incisional
hernia in midline incisions is reported to be 3.0% in gynecological
surgeries [13]. Additionally, one study found that 16% of
incisional hernias occurring within 10 years of laparotomy are
surgically repaired [16]. Based on these findings, surgical hernia
repair was performed on 0.48% of all midline incisions in the study
population. Under these assumptions surgical repair of transverse
incision hernias was performed after 66 of 54.104 cesarean
deliveries during a 10 year period corresponding to an overall
crude incidence of 0.12%. The risk of a hernia in a transverse
incision requiring repair is therefore probably lower than the risk
found in this study. Previous studies have found that the risk of
developing a hernia in a midline compared with a transverse
incision is increased, with odds ratios of 1.68 to 3.33 [20,21]. This
difference most likely explains why more than half the hernia
repairs in our study were performed on hernias in midline
incisions, although the percentage of midline incisions in the
cesarean delivery cohort was low. We found no statistically
significant differences between the hernia repairs performed in a
midline compared with transverse incision regarding time from
cesarean delivery to repair, number of previous cesarean
deliveries, age at the cesarean delivery, or percentage performed
as an emergency procedure.
Factors other than the type of incision have been suggested to
influence the development of incisional hernias. The suture
material and suture technique used to close the fascia have been
shown to affect the risk of incisional hernia in midline incisions. A
Figure 1. Flow through the study. Number in brackets is number of excluded and censored cases found through validation. CD: cesarean
delivery. NA: Not available.
doi:10.1371/journal.pone.0108829.g001
Table 1. Basic characteristics of surgical repairs performed on hernias in midline and transverse incisions.
Transverse incision Midline incision
P
(n = 50) (n = 68)
Age at last cesarean delivery before hernia repair (years) [Mean (SD)] 32 (5) 32 (5) 0.836
*
Number of cesarean deliveries before hernia repair [Median (IQR)] 1.5 (1.0–2.0) 2.0 (1.0–2.8) 0.139
{
Time from cesarean delivery to hernia repair (months) [Median (IQR)] 18.5 (9.6–26.0) 21.7 (11.4–60.8) 0.078
{
Acute hernia repair [n (%)] 2 (4.5%) 2 (3.1%) 1.000
`
Data analyzed with *unpaired t-test,
{
Mann Whitney test, and
`
Fischer’s exact test.
doi:10.1371/journal.pone.0108829.t001
Incisional Hernia after Cesarean Delivery
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suture technique with continuous sutures placed 1 cm apart and
1 cm from the incision using a suture 4 times the length of the
incision has been shown to prevent hernias [31]. Additionally, a
meta-analysis found that slowly absorbable suture material caused
fewer hernias [32]. Unfortunately, there are no studies on closure
techniques of the fascia in transverse incisions for cesarean
delivery. The risk of incisional hernia after cesarean delivery seems
to be so low that randomized trials with incisional hernia as the
primary outcome would need a very large number of participants
and at least 3 years of follow-up. And unfortunately, two current
multifactorial randomized trials with long-term follow-up after
cesarean delivery are not exploring methods to close the fascia
[33,34]. The development of incisional hernias may also be
influenced by factors such as BMI and post-cesarean complications
including infection. Unfortunately these variables were not
available in the Danish registers during the study period and
were not uniformly registered in the available medical records, and
could therefore not be included in this analysis. A case-control
study could theoretically evaluate differences in various risk factors
between cases with a hernia repair and a control group. However,
since data about BMI, post-operative infection, and surgical
technique for fascial closure were not consistently registered in the
records in the 1990s, the study would only be able to add
information about risk differences due to incision type and confirm
previously estimated odds ratios.
This is the largest study to date that gives an estimate of the risk
of developing an incisional hernia requiring repair after cesarean
delivery and the first study with a follow-up time of more than 1
year. However, the study has some limitations that need to be
considered. Register studies are dependent on the rate, complete-
ness, and accuracy of the registration. Both the registration rate
and the validity of type of surgical procedures in the Danish
National Patient Register have been shown to be high, and we
assume that our data are representative [26–28]. The surgical
codes for hernia repair do not contain information about
anatomical location of the hernia explaining the relatively high
rate of hernia repairs that were found to be unrelated to a previous
cesarean delivery through validation. We excluded women with
previous abdominal surgery from our cohort, and there may have
been some cases of hernia repairs after a cesarean delivery in this
group. However, it is unlikely that the incidence is different in the
excluded group compared with our cohort, and thus exclusion of
these women should not have affected our results.
Figure 2. Cumulative incidence of incisional hernias requiring repair after cesarean delivery. CD: cesarean delivery.
doi:10.1371/journal.pone.0108829.g002
Table 2. Cumulative incidence of incisional hernias requiring surgical repair 1, 3, and 10 years after a cesarean delivery.
1 year 3 years 10 years
Hernia repair 0.072 (0.052–0.092) 0.157 (0.127–0.187) 0.197 (0.164–0.231)
Data are expressed as % (95% confidence interval).
doi:10.1371/journal.pone.0108829.t002
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The Danish National Patient Register was established in 1977,
and patients with abdominal surgeries performed before 1977
could not be identified and excluded from our cohort. Addition-
ally, we excluded some cases of hernia repair in the process of
validation due to the identification of previous abdominal
surgeries. This may have caused us to underestimate the actual
incidence of hernia repair after cesarean delivery. But there are
also some factors that may have led to an overestimation of the
actual incidence of hernia repair after cesarean delivery. During
the process of validation, a number of hospital records were not
retrievable. We maintained these unconfirmed cases in the cohort
in order to avoid underestimation. Additionally, more than half
the repairs were of hernias in midline rather than transverse
incisions, the latter being the preferred incision for cesarean
delivery in the Western world [35]. Unfortunately, the distribution
of the two types of incisions in Denmark in the 1990s is unknown,
although the transverse incision was the incision of choice. We
were therefore not able to separately estimate the risk of a hernia
repair in the two types of incisions.
The risk of developing an incisional hernia after a cesarean
delivery that does not require repair was not investigated in this
study. The validity of diagnostic codes in the Danish registries
have been shown to be poor [36,37] and we therefore selected the
surgical code of hernia repair. Medical treatment is free in
Denmark and we therefore assume that clinically important
incisional hernias were treated surgically due to the risk of serious
adverse events (e.g. incarceration). But small hernias may be left
un-treated, and thus the risk of an incisional hernia might be
higher than the risk of surgical hernia repair found in this study.
In conclusion, this study found that the overall risk of having an
incisional hernia requiring repair within 10 years of a cesarean
delivery was 2 per 1000 cesarean deliveries. Most hernias were in
midline incisions in a population in which the transverse incision
was the primary approach at cesarean delivery. Consequently the
risk of developing a hernia in a transverse cesarean incision
following current surgical recommendations is very low and should
not restrict the use of cesarean delivery.
Acknowledgments
We thank Steen Rasmussen, University of Copenhagen, Hvidovre Hospital
for his assistance with data management. He was paid for the service
through project funds.
Edwin Stanton Spencer edited the language in the article and was paid
for the service through project funds.
Author Contributions
Conceived and designed the experiments: AA LK SL NJS. Performed the
experiments: AA LK SL. Analyzed the data: AA SL. Contributed
reagents/materials/analysis tools: SL AA. Contributed to the writing of
the manuscript: AA.
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Incisional Hernia after Cesarean Delivery
PLOS ONE | www.plosone.org 6 September 2014 | Volume 9 | Issue 9 | e108829
... These hernias are defined as ventral hernias, located peripherally to the midline up to 5 cm from the pubic arch [2]. They can occur after numerous surgeries, especially after gynaecological interventions (caesarean section, ovarian interventions, total or partial hysterectomy) [3][4][5][6]. These hernias can be found in the literature as "suprapubic" or "parapubic" incisional hernias. ...
... These hernias can be found in the literature as "suprapubic" or "parapubic" incisional hernias. [4][5][6][7]. ...
... A review found that 2 out of every 1000 deliveries via c-section required surgery for an incisional hernia, that is for 10 years after a csection the risk of developing an incisional hernia was 0.197%. This study was conducted in Denmark and thus we must consider that the risk of developing one is higher in Pakistan considering the C-section rate per woman is much higher 14 . Most studies done have focused either on the risk of developing an incisional hernia or on undertaking a simultaneous repair of a paraumbilical hernia at the time of a csection 15 . ...
Article
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Background: Anterior abdominal wall hernias constitute one of the most common surgical presentations. According to the World Bank data Pakistan has one of the highest birth rates per woman in the region at 3.6 births per woman. In Pakistan there has also been a large increase in C-section rates with nearly 20% of all pregnancies being delivered via C-section, nearly 1 out of every 5 births. Multi-parity is a risk factor for developing paraumbilical hernias and C-sections lead to incisional hernia developments. Methodology: The study conducted was a cross-sectional study at a tertiary care hospital in the department of surgery from 1st June 2021 till 1st September 2021. Any woman presenting with a ventral hernia to the clinic was asked to fill out a questionnaire. 60 women presented over the study period and were enrolled. Results: Fifty five percent paraumbilical hernias and 41.7% incisional hernias were reported. The mean number of pregnancies was 4.10 S.D 1.531 with a range from 0-8. C-sections were 2 times more common than SVDs. Increasing number of pregnancies associated with younger age of onset. Higher number of vaginal deliveries and C-sections were each associated with the development of a ventral hernia. Conclusion: The high fertility rate and C-section rate in Pakistan incurs a huge risk to women developing ventral hernias and poses a burden to the public healthcare system. Keywords: Paraumbilical hernia; parity; Pakistan
... Additionally, current recommendations that state that blunt abdominal entry should be preferred over sharp entry are not supported by this, the largest trial ever undertaken addressing this comparison. 12,13 Although some studies have shown that blunt abdominal entry can also result in a shorter operating time, this does not seem to lead to measurable improvements in clinical outcomes. However, shorter operating times might lead to more eff ective use of theatre time in centres with large numbers of caesarean sections being done. ...
Article
The CORONIS trial reported differences in short-term maternal morbidity when comparing five pairs of alternative surgical techniques for caesarean section. Here we report outcomes at 3 years follow-up.
... Two larger studies in the review were conducted in high-income countries where transverse incision was recommended to limit the occurrence of incisional hernia [21]. These showed incisional hernia repair rates of 0.16% [22] and 0.5 [23] %. The rate of 1.0% in the present study is comparable, though difference in study design makes it difficult to compare results. ...
Article
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Background The rate of caesarean section without medical indication is rising but the risk for surgical complications has not been fully explored. Methods Altogether 79 052 women from the Swedish Medical Birth Register who delivered by caesarean section only from 2005 through 2016 were identified and compared with a control group of women delivering vaginally only from the same register and the same period of time. By cross-linking data with the National Patient Register the risks for bowel obstruction, incisional hernia and abdominal pain were analysed, as well as risk factors for these complications. We also analysed acute complications, uterine rupture, and placenta praevia. Findings Caesarean section is associated with an increased risk for bowel obstruction (OR 2.92; CI 2.55–3.34), surgery for bowel obstruction (OR 2.12; CI 1.70–2.65), incisional hernia (OR 2.71; CI 2.46–3.00), surgery for incisional hernia (OR 3.35; CI 2.68–4.18), and abdominal pain (OR 1.41; CI 1.38–1.44). Smoking, obesity, and more than one section delivery added significantly to the risk for these complications. Interpretation Caesarean section is considered a safe procedure, but awareness of the risk for serious complications is important when deciding on mode of delivery. In this study, more than one section, obesity and smoking significantly increased the risk for complications after caesarean section. Prevention of smoking and obesity among fertile women worldwide must continue to be a high priority.
... [8] Apart from surgery, other associated predisposing factors were ascites, chronic cough, steroid abuse, and child birth. [8] Published data from Italy, [7] Nigeria, [9,10] Yemen, [11] India [12] and Denmark [13] support the above findings. Although incisional hernia may remain silent and asymptomatic for years, it may enlarge over time and lead to complications like pain, bowel obstruction, and strangulation. ...
Article
Background: The steady rise in laparotomy rates, particularly resulting from gynecologic and obstetric procedures in our environment has given rise to corresponding increase in the proportions of incisional hernias (IH). Over the years, discussion on the appropriate repair technique for IH has continued, nevertheless, with advances in laparo-endoscopy and introduction of prosthetic meshes, the surgical treatment has been revolutionized. Aims: The aim of this study is to examine the risk factors and the evolutionary trend in surgical repair in our center. Methodology: This is a descriptive prospective study of adult patients with incisional hernias. The study was carried out in a tertiary health institution from January 2011 to December 2017. Results: A total of 177 patients were recruited, 147 (83.1%) females and 30 (16.9%) males. Nearly two-thirds, 115 patients (65.0%) received prosthetic mesh repair, the rest, 62 patients (35.0%) were fixed using suture-based techniques. Among the 115 mesh repairs, 110 (995.7%) were in females and the remaining five (4.3%) were in males. The most frequent precipitating surgery was caesarean section in 72 patients (40.7%), followed by gynecology operations, 45 patients (25.4%), none-obstetrics and gynecology laparotomies, 50 patients (28.2%) and others, 10 patients (5.7%). Of the 177 patients evaluated, in 99 patients (55.9%) there was history of wound infection in the previous surgery while 24.9%, 5.1%, 4.5% and 1.1% reported that they had prolonged cough, diabetes, jaundice, and urinary obstruction in the peri-operative period of the initiating operations. The rate of recurrence was 17.7% in the non-mesh repairs and 0.0% in the group that had mesh repair. Conclusion: In our locality, the trend over time shows a shift from predominantly anatomic suture-based repair to a tensionless mesh implant with far lower recurrent rates. Laparotomy incisions for obstetric and gynecologic procedures are the most common precipitating incisions.
... Overall, IH (70.3%) was the commonest indication for the abdominal wall reconstruction in this study. It has been cited that IH occurs in approximately 5-15% of laparotomies and may rise to 26% in the context of wound sepsis [16][17][18][19][20][21]. This is followed, simultaneously by divarication of recti and abdominal wound dehiscence, each accounting for less than a tenth (8.8%) of the reconstructions done (Table 2). ...
Article
Introduction: the role of surgery in managing massive midline abdominal wall defects has continued to rise, leading to higher demand for more effective techniques in order to limit recurrences. There is paucity of data on this subject in Southeast Nigeria. The aim of this study is to document the indications and challenges of treatment of complex, midline abdominal wall defects in our centre. Methods: this was a cross-sectional study of adult patients with complex, midline abdominal wall defects managed with mesh implants over a five-year period. Results: a total of 182 adult patients, predominantly females 160(87.9%), received mesh implants for complex abdominal wall defects. The common indications were incisional hernia 128(70.3%), abdominal wound dehiscence 16(8.8%) and divarication of recti 16(8.8%). About one-third 62(34.1%) of the patients required additional abdominoplasty procedure. Delay towards prompt surgical repair was noted in 168(92.3%) patients, notably due to financial constraints 32(17.6%) followed by comorbidities requiring serial assessments 24(13.2%). Superficial wound infection rate was 5.5% while deep (mesh) infection was noted in two (1.1%) patients. Recurrence and perioperative mortality rates were 1.1% and 1.6% respectively. Diabetes mellitus in obese female patients was an independent predictor of perioperative death (p=0.000). Conclusion: the most common indication for abdominal wall reconstruction in our environment is incisional hernia. The use of prosthetic meshes to repair complex abdominal wall defects is largely safe and effective in our practice, but timely reconstruction is commonly hampered by multi-faceted economic, clinical and pathological barriers.
Article
Purpose This retrospective study aims to describe morphological and therapeutic peculiarities of the suprapubic incisional hernia (SIH) encountered after a Joël-Cohen laparotomy. Patients and Method Serie-report: 9 patients had an SIH, 2 were sub-umbilical and did not concern the suprapubic scar, 3 were central, 2 on the whole length of the suprapubic scar, and 2 were bilateral in one case associated to a sub-umbilical incisional hernia. Results SIH were wide openings, with a hernial fascia constituted from the anterior fascia, without connexion with the parietal peritoneum, in a sub-umbilical position above the suprapubic scar, or through the suprapubic scar. Rectus muscle was ruptured or sclerosed. There were 2 distinct defects, an anterior one through the anterior fascia, and a posterior one between the rectus muscles. The parietal peritoneum was retracted leaving bare the posterior side of the rectus muscles. There was an interstitial retro-fascial space, so the SIH was bisaccular. When releasing the parietal peritoneum was not feasible, the prosthesis was placed in a retro-fascial space. When the parietal peritoneum was released, the prosthesis was placed in a preperitoneal space. The anterior defect closure was not always completely feasible, fulfilled with a Vicryl prosthesis. One patient presents an abdominal wall bulging in case of efforts. Conclusion SIH after a Joël-Cohen laparotomy is wide and dilapidating. The cure is difficult. This technique should be reserved to real emergency obstetrical procedure. We highlight the importance of the parietal peritoneum closure after gynecological or obstetric surgery.
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Introduction: The digitalization of medicine has led to a considerable growth of heterogeneous health datasets, which could improve healthcare research if integrated into the clinical life cycle. This process requires, amongst other things, the harmonization of these datasets, which is a prerequisite to improve their quality, re-usability and interoperability. However, there is a wide range of factors that either hinder or favor the harmonized collection, sharing and linkage of health data. Objective: This systematic review aims to identify barriers and facilitators to health data harmonization-including data sharing and linkage-by a comparative analysis of studies from Denmark and Switzerland. Methods: Publications from PubMed, Web of Science, EMBASE and CINAHL involving cross-institutional or cross-border collection, sharing or linkage of health data from Denmark or Switzerland were searched to identify the reported barriers and facilitators to data harmonization. Results: Of the 345 projects included, 240 were single-country and 105 were multinational studies. Regarding national projects, a Swiss study reported on average more barriers and facilitators than a Danish study. Barriers and facilitators of a technical nature were most frequently reported. Conclusion: This systematic review gathered evidence from Denmark and Switzerland on barriers and facilitators concerning data harmonization, sharing and linkage. Barriers and facilitators were strictly interrelated with the national context where projects were carried out. Structural changes, such as legislation implemented at the national level, were mirrored in the projects. This underlines the impact of national strategies in the field of health data. Our findings also suggest that more openness and clarity in the reporting of both barriers and facilitators to data harmonization constitute a key element to promote the successful management of new projects using health data and the implementation of proper policies in this field. Our study findings are thus meaningful beyond these two countries.
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Objectives: This report presents 2011 data on U.S. births according to a wide variety of characteristics. Data are presented for maternal characteristics, including age, live-birth order, race and Hispanic origin, marital status, attendant at birth, method of delivery, and infant characteristics (e.g., period of gestation, birthweight, and plurality). Birth and fertility rates are presented by age, live-birth order, race and Hispanic origin, and marital status. Selected data by mother's state of residence and birth rates by age and race of father also are shown. Trends in fertility patterns and maternal and infant characteristics are described and interpreted. Methods: Descriptive tabulations of data reported on the birth certificates of the 3.95 million births that occurred in 2011 are presented. Denominators for population-based rates are postcensal estimates derived from the U.S. 2010 census. Birth and fertility rates for 2001-2009 are based on revised intercensal population estimates. Denominators for 2011 and 2010 rates for the specific Hispanic groups are derived from the American Community Survey; denominators for earlier years are derived from the Current Population Survey. Results: The number of births declined 1% in 2011 to 3,953,590. The general fertility rate also declined 1%, to 63.2 per 1,000 women aged 15-44. The teen birth rate fell 8%, to 31.3 per 1,000 women. Birth rates declined for women in their 20s, were unchanged for women aged 30-34, and rose for women aged 35-44. The total fertility rate (estimated number of births over a woman's lifetime) declined 2% to 1,894 per 1,000 women. The number and rate of births to unmarried women declined; the percentage of births to unmarried women was essentially stable at 40.7%. The cesarean delivery rate was unchanged from 2010 at 32.8%. The preterm birth rate declined for the fifth straight year to 11.73%; the low birthweight rate declined slightly to 8.10%. The twin birth rate was not significantly changed at 33.2 per 1,000 births; the rate of triplet and higher-order multiple births also was essentially stable at 137.0 per 100,000.
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Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (http://www.strobe-statement.org/) should be helpful resources to improve reporting of observational research.
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Uterine rupture is a rare but severe complication in pregnancies after a previous cesarean section. In Denmark, the monitoring of uterine rupture is based on reporting of relevant diagnostic codes to the Danish Medical Birth Registry (MBR). The aim of our study was to examine the validity of registration of uterine rupture in the MBR within the population of pregnant women with prior cesarean section by conducting a review of the medical records. We reviewed 1709 medical records within the population of singleton pregnant woman delivering at term between 1997 and 2007. We retrieved the medical records of all women in the MBR with a code for uterine rupture during labor regardless of whether or not a prior cesarean section had been reported to the registry. In addition medical records of all women with a code for previous cesarean section and delivery of a child with adverse perinatal outcome were retrieved. Among women recorded in the MBR with a previous cesarean section and uterine rupture, only 60.4% actually had a uterine rupture (partial or complete). At least 16.2% of complete uterine ruptures were not reported to the registry. Considering only complete uterine ruptures, the sensitivity and specificity of the codes for uterine rupture were 83.8% and 99.1%, respectively. During the study period the monitoring of uterine rupture in the MBR was inadequate.
Article
Objective: In women undergoing delivery by caesarean section, do the following alternative surgical techniques affect the risk of adverse outcomes: single- versus double-layer closure of the uterine incision; closure versus nonclosure of the pelvic peritoneum; liberal versus restricted use of a subrectus sheath drain? Design: Pragmatic, 2 × 2 × 2 factorial randomised controlled trial. Setting: Hospitals in the UK and Italy providing intrapartum care. Population: Women undergoing their first caesarean section. Methods: The interventions were alternative approaches to the three aspects of the caesarean section operation. A telephone randomisation service was used. Surgeons could not be masked to allocation, but women were unaware of which allocations had been used. The analysis was by intention-to-treat, with a prespecified subgroup analysis for women 'in labour' or 'not in labour' at the time of caesarean section. Main outcome measures: Maternal infectious morbidity. Results: A total of 3033 women were recruited. Overall, the risk of maternal infectious morbidity was 17%. For each pair of interventions, there were no differences between the arms of the trial for the primary outcome: single- versus double-layer closure of the uterine incision [relative risk (RR) = 1.00, 95% confidence interval (95% CI) = 0.85-1.18]; closure versus nonclosure of the pelvic peritoneum (RR = 0.92, 95% CI = 0.78-1.08); liberal versus restricted use of a subrectus sheath drain (RR = 0.92, 95% CI = 0.78-1.09). There were no differences in any of the secondary morbidity outcomes and no significant adverse effects of any of the techniques used. Conclusions: These results have implications for clinical practice, particularly in relation to current guidance on the closure of the peritoneum, which suggests that nonclosure is preferable. The potential effects of these different surgical techniques on longer term outcomes, including the functional integrity of the uterine scar during subsequent pregnancies, are now becoming increasingly important for guiding clinical practice.
Article
While transverse incision is the recommended entry technique for cesarean delivery in high-income countries, it is our experience that midline incision is still used routinely in many low-income settings. Accordingly, international guidelines lack uniformity on this matter. Although evidence is limited, the literature suggests important advantages of the transverse incision, with lower risk of long-term disabilities such as wound disruption and hernia. Also, potential extra time spent on this incision appears not to impact neonatal outcome. Therefore, we suggest that it is time for a change in guidelines for low-income settings in which resources are limited for treating complications that may be life threatening.
Article
Background: The CORONIS Trial was a 2×2×2×2×2 non-regular, fractional, factorial trial of five pairs of alternative caesarean section surgical techniques on a range of short-term outcomes, the primary outcome being a composite of maternal death or infectious morbidity. The consequences of different surgical techniques on longer term outcomes have not been well assessed in previous studies. Such outcomes include those related to subsequent pregnancy: mode of delivery; abnormal placentation (e.g. accreta); postpartum hysterectomy, as well as longer term pelvic problems: pain, urinary problems, infertility. The Coronis Follow-up Study aims to measure and compare the incidence of these outcomes between the randomised groups at around three years after women participated in the CORONIS Trial. Methods/Design: This study will assess the following null hypotheses: In women who underwent delivery by caesarean section, no differences will be detected with respect to a range of long-term outcomes when comparing the following five pairs of alternative surgical techniques evaluated in the CORONIS Trial: 1. Blunt versus sharp abdominal entry 2. Exteriorisation of the uterus for repair versus intra-abdominal repair 3. Single versus double layer closure of the uterus 4. Closure versus non-closure of the peritoneum (pelvic and parietal) 5. Chromic catgut versus Polyglactin-910 for uterine repair The outcomes will include (1) women’s health: pelvic pain; dysmenorrhoea; deep dyspareunia; urinary symptoms; laparoscopy; hysterectomy; tubal/ovarian surgery; abdominal hernias; bowel obstruction; infertility; death. (2) Outcomes of subsequent pregnancies: inter-pregnancy interval; pregnancy outcome; gestation at delivery; mode of delivery; pregnancy complications; surgery during or following delivery. Discussion: The results of this follow-up study will have importance for all pregnant women and for health professionals who provide care for pregnant women. Although the results will have been collected in seven countries with limited health care resources (Argentina, Chile, Ghana, India, Kenya, Pakistan, Sudan) any differences in outcomes associated with different surgical techniques are likely to be generalisable throughout the world. Trial registration: ISRCTN31089967
Article
Incisional hernia is a late complication of laparotomy for which an evidence-based prohylactic approach is still lacking. Postoperatively, incisional hernias occur because of multiple factors. Preoperative comorbidities belong to these risk factors. A risk reduction related to concomitant diseases mostly does not succeed. There is a range of studies comparing the techniques of surgical wound closure. A consensus of these is that a running suture of the fascia with slowly absorbable or non-absorbable sutures results in the lowest incidence of incisional hernias. A one-cm distance between the stitches and a minimal distance of one cm to the fascial margin as well as a 4 : 1 suture length to wound length ratio are still valid principles. In any case, solely optimising the surgical technique of the abdominal wall closure is not able to reduce the incidence of incisional hernias. Prevention of postoperative complications by adequate pain management, respiratory training and early mobilisation are procedures to reduce the incidence of incisional hernias. However, systematic studies are lacking. To avoid an incisional hernia, only a practical approach remains which, however, does not meet the requirements of evidence-based medicine.