If you have had a previous c-section, in a subsequent pregnancy you will have two options for delivery: having a repeat elective (scheduled) c-section or having a trial of labour in the hopes of having a vaginal delivery (VBAC = vaginal birth after c-section). Research has shown that 7 of 10 women who have previously had a caesarian section can successfully have a vaginal delivery in a subsequent pregnancy. Most women prefer to have a vaginal birth because it reduces the time spent in hospital, reduces the need for pain medication, reduces the risk of infection, and has a faster recovery time. Repeated c-sections increase the risk of abnormal implantation of the placenta, and this risk increases with each additional c-section. C-sections become more challenging to perform with each additional c-section and therefore become more prone to complication. For these reasons, vaginal delivery is especially ideal if you know that you want to have many children.
The likelihood of a successful VBAC varies somewhat depending on the reason for your first c-section. If the reason for your c-section is unlikely to recur (for example a breech baby, or an abnormal fetal heart rate), you probably have a higher likelihood of success than someone who had to have a c-section because the baby just would not fit through the pelvis (especially if you are growing an equally large baby this time).
Women who are pregnant who have a scar on their uterus from a previous c-section carry a small risk of uterine rupture (where the scar opens up). The risk of uterine rupture to the mother includes bleeding, hysterectomy, and rarely death. The risk of uterine rupture to the baby includes brain damage, damage to other organs, and death.
Uterine rupture can occur in women who have not had a c-section, although it is rare. In women who have not had a previous c-section, the risk of uterine rupture is 1 in 5,000 and the risk that the baby will have major complications including death as a result of that is 1 in 20,000.
In women who have had a previous c-section and choose to have a scheduled repeat c-section before labour, the risk of uterine rupture is 1 in 350 and the risk the baby will have major complications including death as a result of that is 1 in 1,400.
In women who have had a previous c-section and attempt to labour and have a vaginal birth, the risk of uterine rupture is 1 in 200 and the risk that the baby will have major complications including death as a result of that is 1 in 800.
If medications are required to induce labour or strengthen contractions during labour, there is a lower success rate for vaginal birth and the risk of uterine rupture is 1 in 100 and the risk the baby will have major complications as a result of that is 1 in 400.
In women who are attempting to have a VBAC, we use continuous fetal monitoring in labour. The first sign of uterine rupture is usually an abnormal change in the fetal heart rate. If this is seen, then proceeding to c-section is recommended. Labour can continue as long as the fetal heart rate is normal and progress is being made. A woman can change her mind at any time about trying to have a VBAC or about having an elective repeat c-section.
The standard of care for obstetrics is that a c-section should be able to be initiated within 30 minutes of deciding it needs to be done. At Brockville General Hospital, obstetricians, anesthetists, OR nurses, and surgical assistants are on home call. That means that when nothing imminent is happening, these staff can be at home but are ready to come in when needed. We are organized to initiate a c-section within 30 minutes of deciding to do so. Despite this fulfilling the standard of care, there is the possibility that there could be an adverse outcome.
A decision to have a repeat c-section or try to have a VBAC is a very personal one. You will need to discuss this with your care provider and your partner. Some women will decide that if they go into spontaneous labour prior to a certain date that they will try to VBAC. If they do not go into labour by that date they may decide to have a repeat c-section rather than be induced. Other women do not want to try to VBAC at all, and others want to do everything possible to try to have a vaginal delivery. We will do everything we can to answer your questions and support you in your choice.