Birth after caesarean: choosing between VBAC and a repeat caesarean

A previous caesarean does not close the door on a vaginal birth. The NHS states that most women who have had a caesarean can safely have a vaginal delivery for their next baby. What changes is how labour is looked after, because the scar in the womb is a point of weakness that labour can, rarely, tear open.

Your midwife or obstetrician should offer a conversation, ideally in the second trimester and again in the third, so that you have time to think. It should cover your own chances of success, the risks to you and the baby of each route, and your preferences for the birth experience.

The Royal College of Obstetricians and Gynaecologists reports that about three out of four women with one previous caesarean and an otherwise straightforward pregnancy who go into labour naturally give birth vaginally. If you have also had a vaginal birth at some point, the figure rises to 8 or 9 out of 10.

Some things lower the odds: a reason for the first caesarean that is still present, a high BMI, a large baby, an induction of labour, or going past your due date. These do not rule VBAC out, but they are part of an honest estimate of your chances.

About 25 in 100 women who plan a VBAC end up needing an emergency caesarean. An emergency operation carries more risk than a planned one, including more bleeding and infection.

The most serious VBAC-specific risk is separation or rupture of the scar, about 1 in 200 women according to the RCOG. This risk rises two to three times when labour is induced. The leaflet adds that the risk of brain injury to the baby or of stillbirth around labour is similar to that of a first labour.

With a planned repeat caesarean the chance of scar rupture falls to about 1 in 1,000, and the risk of serious problems for the baby linked with labour is about 2 in 1,000. Between 4 and 5 in 100 babies born by planned caesarean at or after 39 weeks have temporary breathing difficulty.

Surgery brings recovery time, a higher chance of infection and blood clots, and consequences for later pregnancies: the more caesareans, the higher the chance of placental problems such as placenta praevia and placenta accreta. That is why the likely size of your family can matter to the decision.

The RCOG lists situations where a planned vaginal birth is generally not recommended.

• Three or more previous caesareans.

• A previous rupture of the womb.

• A classical caesarean scar, which runs into the upper, muscular part of the womb.

• Another reason this pregnancy needs a caesarean, such as a low-lying placenta.

Plan to give birth in a consultant-led unit with theatre and anaesthetic staff available at all times. You will usually be advised to have continuous monitoring of the baby's heart, a drip in place and a midwife close by. Pain that is constant between contractions, a change in the baby's heart rate, vaginal bleeding or a sudden stop in contractions need immediate review.

If you choose induction, it is discussed carefully, since it is linked with a higher chance of both caesarean and scar rupture. You can change your mind at any stage, including after labour starts.