Maternal and Perinatal Outcomes.
Forty-seven studies presented data on maternal outcomes including
uterine rupture (n=39), uterine dehiscence (n=16), maternal mortality
(n=44), blood transfusion (n=10), and hysterectomy (n=17) (Table 2).
Forty-five studies presented data on perinatal outcomes including
stillbirth (n=20), neonatal mortality (n=18), perinatal mortality
(stillbirth and neonatal mortality combined) (n=18), low Apgar score
(n=22), and neonatal ICU admission (n=11) (Table 2).
Although 43 studies reported on uterine rupture or dehiscence, very few
provided a definition (n= 4, 9%) distinguishing between rupture and
dehiscence, and definitions varied across studies. Given difficulty
separating the two conditions and inconsistencies, we combined uterine
rupture and dehiscence to obtain a single summary estimate. Over the
29,823 deliveries amongst studies reporting uterine ruptures or
dehiscence, there were 386 cases of uterine rupture or dehiscence for an
overall weighted mean of 1.3% (± SD 1.6). There was regional variation
in uterine rupture/dehiscence rates, with the lowest reported rate of
1.3% in West Africa and the highest rate of 8.8% in Central Africa.
(Table 3)
Seventeen studies provided data on maternal and/or perinatal outcomes
with a TOLAC and ERCS comparison group, representing 22,599 births in 8
countries (Figure 2). Pooled uterine rupture/dehiscence rate in this
group (n=11 studies) was 1.4% in the TOLAC group and 0.2% in the ERCS
group. However, the risk for uterine rupture did not differ from TOLAC
vs ERCS (OR 1.54 (0.63-3.75 95% CI)). This did not differ when
restricted to the nine studies which reported only on women with one
prior CS [OR 1.70 (0.63-4.6 95%CI)] or with a MINORS score ≥ 16
[OR 1.77 (0.56-5.56 95% CI)].
Maternal mortality rates did not differ by TOLAC vs ERCS (n=13 studies)
(0.3% vs <0.1%, OR 0.77 (0.30-1.98) with similar findings in
studies restricted to women with only one prior CS or with a MINORs
score > 16. Only six studies reported on perinatal
mortality by comparison group. No studies with TOLAC and ERCS comparison
groups separated stillbirth and neonatal mortality. Pooled rates
demonstrated that perinatal mortality was higher in women undergoing
TOLAC (5%) compared to ERCS (1%), OR 3.3 (1.5-6.9 95%CI).