Background
Caesarean section is the most commonly performed abdominal surgical procedure, and the incidence is rising worldwide [
1,
2]. The percentage of births by Caesarean Section (CS) is low in the eastern and southern African region (6.2%), but there is a large variation between and within African countries [
1,
3]. In the case of previous CS, sometimes CS is the only option offered, but in most settings, women can either choose an elective CS or a trial of labour (TOL) [
4]. In low-income countries (LICs), both the risks of TOL as well as the risks of repeat CS are increased compared to high-income countries [
5‐
8]. Maternal mortality after CS in Africa is 50 times higher than in high-income countries (HICs), mostly due to anaesthesia complications and haemorrhage [
9,
10]. The most feared complication of TOL is uterine rupture (UR), which occurs in 0.47% of women who have a TOL [
11]. In low-income countries, UR is reported to occur in up to 6.7% of cases, but these numbers are not reliable since these studies describe only in-hospital deliveries and do not report population data [
12,
13]. Adhesion formation after surgery can be the cause of chronic pain and infertility; both common long-term maternal morbidities after CS, as well as a reason for readmission and repeated surgery [
14]. Adhesions are associated with both a longer operation time and intra-operative morbidity such as bladder lesions [
14,
15]. In subsequent pregnancies, the advantages of vaginal birth after CS (VBAC) are more relevant, since the risks of UR and abnormal placentation increase with the number of previous CS [
16]. In many African countries, the total fertility rate (TFR) is high, making VBAC after previous CS an essential strategy in reducing the rising rate of CSs and its associated morbidities [
17]. Rates of VBAC vary between 38 and 48% across African countries and hospitals [
13,
17,
18].
Internationally, there is debate concerning surgical CS techniques and adhesion formation. Two large meta-analyses examined closure of the visceral peritoneum and reported opposite conclusions [
19,
20]. In Ndala Hospital, Tabora Region, Tanzania, different surgical techniques for CS are in use, which are closure and non-closure of the visceral peritoneum. We performed a retrospective study to assess maternal and neonatal morbidity and mortality after repeat CS in this rural hospital in an LIC and evaluated the effect of surgical technique on the formation of adhesions.
Results
Among the 3966 women who gave birth in the hospital during the 22-month study period, there were 450 CSs (11.3%) of which 321 (71%) were 1
st CS, 80 (18%) were 2
nd CS, 36 (8%) were 3
rd CS, 12 (3%) were 4
th, and one was a 5
th CS (0.2%). In 99% of patients (115/116) who underwent a 2
nd or 3
rd CS, presence and severity of adhesions were reported. Adhesions were considered to be severe in 56% (44/79) of 2
nd CS and in 64% (23/36) of 3
rd CS (
p = 0.08). For 1
st CS, the skin incision was more often transverse when operated in Ndala, compared with those who underwent surgery in other hospitals: 71% (54/76) vs 8% (3/38),
p < 0.01. The baseline characteristics of women with repeat CS (data for 2
nd and 3
rd CS only) are shown in Table
1.
Table 1
Characteristics of women with repeat CS
Operative characteristics |
Median estimated blood loss | 150 (100–300) | 225 (150–300 | 0.98 |
(ml, interquartile range) | (n = 78) | (n = 36) | |
Classical incision in uterus | 1 (1%) | 2 (6%) | 0.23 |
Inadequate lower segment | 15 (19%) | 10 (28%) | 0.27 |
Total number tube ligation | 26 (33%) | 27 (75%) | 0.01 |
Skin incision |
Midline | 36 (45%) | 25 (69%) | 0.01 |
Transverse | 43 (54%) | 11 (31%) | 0.02 |
Combined (T-incision) | 1 (1%) | 0 | 0.69 |
Adhesions (total) | n = 79 | n = 36 | |
Minor | 35 (44%) | 23 (64%) | 0.08 |
Severe | 44 (56%) | 13 (36%) | |
Neonatal outcome | n = 82 | n = 32 | |
Stillbirth | 8 (10%) | 0 | 0.05 |
Child alive, Apgar score < 7 at 5’ | 2 (2%) | 0 | 0.48 |
Adverse neonatal outcome (stillbirth and Apgar score < 7 at 5) | 10 (12%) | 0 | 0.02 |
Hospital previous CS | n = 80 | n = 72 | |
Ndala | 57 (71%) 4 | 8 (67%) | 0.54 |
Other hospital | 23 (29%) | 21 (29%) | 0.95 |
Unknown | 0 | 3 (4%) | 0.10 |
Adverse perinatal outcomes were observed more often (12% vs 0%,
p = 0.02) in women with 2
nd CS than 3
rd CS. Thirty-eight of 49 women (78%) who were booked for an elective repeat CS were in labour before the planned surgery. Adverse neonatal outcome was more common when severe adhesions were present (16% vs 6%), but this was not statistically significant (
p = 0.14, Table
2). A transverse skin incision was statistically significantly associated with fewer adhesions than a midline incision.
Table 2
Severity of adhesions in second CSa
Median age (yrs, interquartile range) | 22 (20–26) | 25 (20–30) | 0.04 |
Median blood loss (ml, interquartile range) | 150 (100–400) | 175 (120–300) | 0.79 |
Neonatal outcome | n = 45 | n = 36 | |
Stillbirth | 6 (14%) | 1 (3%) | 0.10 |
Child alive, Apgar Score of < 7 at 5’ | 1 (2%) | 1 (3%) | 0.69 |
Adverse neonatal outcome (stillbirth or Apgar Score < 7 at 5) | 7 (16%) | 2 (6%) | 0.14 |
Characteristics at 1st CS |
Uterotomy closure in 2 layers | 59% (19/32) | 71% (15/21) | 0.55 |
Transverse incision | 35% (15/43) | 62%(21/34) | 0.03 |
Closure visceral peritoneum | 59% (19/32) | 53% (16/30) | 0.82 |
Closure rectus muscles | 16%(5/32) | 20% (4/20) | 0.72 |
Wound infection | 14% (3/22) | 6%(1/16) | 0.62 |
Of the 13 cases with multiple repeat CS (12 women with a 4th CS, one with a 5th CS), all neonates had Apgar scores above seven at 5 min, and no neonatal or severe acute maternal morbidity or mortality was recorded.
Discussion
In this rural hospital in an LIC, severe adhesions after CS are common. Adverse neonatal outcome is observed in 12% of 2nd CS, while this was not the case in 3rd CS. Half of the patients had a midline incision during their first CS, which was associated with severe adhesions.
The majority of patients (78%) who were booked for an elective repeat CS were in labour before the planned surgery. This has been described in a study from Uganda as well [
4]. No data were collected on the scheduled surgery date, and it is unclear if the women did not come for their surgical appointment, or if labour started beforehand. The first could be because women who prefer vaginal birth are afraid they are not allowed a TOL in the hospital and deliberately arrive late, with higher risk of adverse outcome [
4,
25]. The latter could be explained by the fact that no reliable gestational age was available and the planned CS was intentionally planned late to prevent accidental iatrogenic preterm birth. The statistically lower incidence of adverse perinatal outcome in 3
rd CS (0% compared to 12% in 2
nd CS,
p = 0.02) suggests when when they are advised not to have a TOL, women present in time.
We observed a high incidence of adverse perinatal outcome after 2
nd CSs (12%). This might reflect the high general perinatal mortality rate in emergency CSs in a low-resource setting, which has been reported to be up to 19% [
26]. In our hospital the perinatal mortality in 1
st CSs is unknown. The aim of this study was to evaluate surgical techniques in CS, but our research has also provided insight in the practice of TOL and repeat CS. Because of the risk of selection bias and without information on successful VBAC rates, this study is not suited to address the risks and benefits of elective CS vs TOL. However, the finding of such a high incidence of adverse perinatal outcomes in 2
nd CS (after TOL) warrants further research into the practice of TOL in our hospital. A new study to assess the safety of TOL after a previous CS in Ndala Hospital has already started.
This study found a prevalence of 56% of severe adhesions after the first CS. This is similar to findings of a recent study in Ghana [
27]. Adhesions are a recognised cause of maternal morbidity and a frequent finding in repeat CS [
28]. The relationship between adhesions and surgical technique was only examined in women with a 2
nd CS. Because of the smaller number of higher order repeat CS, as well as different techniques used in previous CS, finding an association was not possible for this group.
In many studies, maternal and perinatal mortality are not significantly different in women with or without adhesions. Adhesiolysis increases the time to delivery of the child and makes the costs significantly higher [
29‐
31]. These studies were conducted in HICs, with a low general perinatal mortality, and CS were performed by medical specialists under optimal conditions. In LICs, the consequences of adhesions could be more severe, which can explain the trend we found towards a higher neonatal mortality rate.
Many studies have been conducted to identify ways to prevent adhesions by assessing surgical techniques, as well as pharmacotherapeutic “adhesion barriers” [
32,
33]. Whether closure of the peritoneum during CS affects (reduces or increases) the incidence of adhesions is still debated [
19,
20]. Reviews are based on uncontrolled prospective and retrospective studies. Long-term results of the Coronis RCT reassuringly showed no difference in any outcomes related to adhesions (such as chronic pain and infertility) after closure or non-closure of the peritoneum [
34]. Long-term results of the CAESAR RCT are expected as well [
35]. In the meantime, arguments for non-closing are the shorter operating time and the use of less suture material. Still, if closing the peritoneum reduces adhesions, this investment could easily be worthwhile. This is why some authors have already argued for the closure of the peritoneum [
36]. In our retrospective study, there was no association between the closure of the peritoneum and the presence of adhesions.
The difference in the type of incision between patients operated in Ndala Hospital and other hospitals highlights the generally low rate of transverse incisions in LICs [
37]. Ndala Hospital has regularly had foreign doctors performing and teaching CS using Pfannenstiel or Misgav-Ladach techniques with a transverse incision [
38]. In Tanzania, many domestically educated doctors are only trained in performing CS with subumbilical midline incisions. This explains the difference in 1
st CS techniques found in this study (71% transverse incisions for CSs performed in Ndala, 8% when CS was performed elsewhere). The WHO advises midline incision because it is easier when using local anaesthesia [
39]. However, transverse incisions have been shown beneficial for different short-term outcomes (such as pain and wound infection) in a low-resource setting [
40]. RCTs in general surgery have shown an increased risk of incisional hernias in midline incisions [
41]. For this, as well as for cosmetic reasons, transverse skin incision could be the technique of choice [
37]. To our knowledge, no studies have examined adhesion formation following different CS skin incisions. In our research, we found significantly fewer adhesions after a previous transverse incision.
In this retrospective study, the significantly higher maternal age at second CS in women with severe adhesions could be either a finding due to bias or a biological effect. Recently, another large study has also found an increase in adhesion formation in women ≥35 years (adjusted odds ratio 1.28, 95% CI: 1.05–1.55) [
42].
Study limitations
There could be confounding by indication, as doctors could decide for themselves whether to close the peritoneum and observation bias in recognising and noting adhesions. The presence and subjective severity of adhesions was a regular part of the operating report. We stratified the presence of adhesions in two groups, without details of the location or a more precise grading, such as has been used in prospective studies [
43]. Another bias could be caused by women with many adhesions being less likely to become pregnant. Since most midline incisions were done in other hospitals, different patient and doctor characteristics could be a confounder for the increased number of adhesions after a midline incision CS. Information on perinatal outcome is limited to the Apgar score at 5 min without knowledge of the condition at discharge; there is no long-term follow up or registration of perinatal mortality. Strengths of this study are both the relatively high number of patients and information at the level of rural district hospitals in an LIC, which allowed us to compare local outcomes to larger studies in the literature.
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