Thanks to an ignorant point of view perpetuated by doctors during most of the 20th century and verbalised at the New York Association of Obstetricians & Gynecologists in 1916 (“Once a cesarean, always a cesarean.”), vaginal birth after caesarian has been much maligned. But views are thankfully changing. Whilst precautions must be taken, the risks surrounding the VBAC and far less than was once feared. This article outlines what you need to know if you’re considering it.
The scar from your previous caesarean is strong. While many people fear that the scar will rupture, and cause the death of the Mother and/ or her Child, medical studies have shown that this risk is greatly overstated.
The only way that VBAC differs from other labours is the small increased risk of uterine rupture – about 0.4% (one in 250). The risk of uterine rupture prior to elective repeat caesarean is 0.2%
To put this risk into some perspective, consider that the probability of requiring a caesarean section for other emergency obstetric situations (not related to the previous caesarian section), such as acute foetal distress, cord prolapse or ante partum haemorrhage is up to 30 times higher.
Early VBAC studies did not always distinguish between a scar rupture and dehiscence. The latter is a partial separation of the uterine wall with little or no symptoms and minimal (if any) maternal or foetal morbidity. The risk of uterine dehiscence or rupture combined occurs with the same frequency, up to 2%, whether a woman choses VBAC or planned repeat caesarean.
A recent Australian study estimated the risk of uterine rupture in VBAC at 0.3% (one in 300). In that study, the risk of the baby dying because of uterine rupture in a woman trying for VBAC was 0.05% (one in 2000). It has been suggested that between 693 and 3332 women would need to undergo elective repeat caesarean to prevent a single baby death attributable to VBAC.
A VBAC, where not medically contraindicated (advised against) has advantages for the baby, too. The contractions of labour massage and stimulate the baby and get him/her ready for birth. Waiting until labour starts assures that the baby is ready to enter the world, rather than being immature, with lungs that may not be able to cope with life outside his/her mother’s protective womb.