Vaginal birth after caesarean section versus elective repeat caesarean section: assess neonatal downstream outcomes too
We thank Ms Cohain and Dr Bewley for their interest in our work.1 We agree that strategies to ultimately decrease the number of women undergoing multiple repeat caesarean sections should include to safely limit the rate of primary caesarean section. However, we disagree with their interpretation of our findings that vaginal birth after caesarean section (VBAC) may be overall safer in birth centres than in hospitals. Even though uterine rupture is a rare complication, it is associated with maternal and neonatal severe morbidity and mortality. The evidence shows that delays in delivery and treatment of uterine rupture increase perinatal morbidity and mortality.2 While these delays can be kept to a minimum in hospitals who have the staff and ability to perform emergency caesarean section, these delays cannot be avoided in birth centres who have to transfer out women with suspected uterine rupture.
We would also like to point out that the 87% successful VBAC rate in birth centres reported in Lieberman et al.3 study cannot be compared with the VBAC rate of 9.2% in USA in 2004.4 The denominator for this 9.2% VBAC rate comprises all women with a previous caesarean section, whether or not they were eligible for a trial of labour and whether or not they had a trial of labour, as opposed to the denominator for the birth centres which includes only women who were eligible for a trial of labour and attempted a VBAC. Furthermore, this high rate of VBAC success in birth centres is at least partially due to the fact that these women were a highly selected population with good prognostic factors for achieving a successful VBAC (all women with known medical or obstetric complications were excluded, all of them went into spontaneous labour and almost half of them had had a prior vaginal delivery); in fact, when women with a prior vaginal delivery were excluded, the VBAC success rate was 80.9%, comparable to the success rate reported in studies done in US hospitals.5
We believe that if we want to reverse the downtrend in VBAC attempts—and the increase in repeat caesarean sections with their morbidity—that we have witnessed in the past 10 years, we must ensure that women are attempting VBAC only in the safest environments; we do not believe that birth centres are the safest environment for women attempting a VBAC.