Vaginal Birth After Cesarean - written by Tamara Jessiman, CNM
Did you know that all VBAC's are not the same? VBAC stands for Vaginal Birth After Cesarean and means just that: delivering a baby vaginally in a subsequent pregnancy after having had a previous cesarean section. When a woman has a cesarean section, a scar is left on her uterus which is potential a weak spot on the uterus that could open with the forces of labor contractions. Because of this, it has been recommended that only hospitals with immediate anesthesia and surgeon availability be allowed to have VBAC's in order to be able to provide an immediate repeat cesarean section in the event of a problem. We are very pleased that Mount Auburn Hospital has this ability to accommodate VBAC's and in fact many of the women we care for come to us for just that reason. The overall success rate of women attempting a VBAC is between 60-80% nationally. The Midwives At Mount Auburn have a success rate of about 75-80%.
If you have had a previous cesarean section and are pregnant and considering trying to have a vaginal birth, you should talk to your midwife. Depending on the circumstances surrounding the type of cesarean section you had and the reason, it may or may not be advisable to have a TOLAC (Trial of Labor After Cesarean). For example, the majority of cesarean sections done in the United States are done by a "low transverse" incision on the uterus. The risk of the incision opening during labor with this type of cesarean section is the lowest: about 0.2 to 1.5%. If you had a vaginal birth prior to your cesarean section, or spontaneously went into labor in a prior pregnancy, this would actually lower the likelihood of the incision opening. Requiring an induction of labor, having more than one previous cesarean section, or having a big baby would potentially increase the risk.
In addition, the reason for your first cesarean section is very important when considering a TOLAC. If your cesarean was done for a malpresentation (such as breech), the success rate for a VBAC is over 80%. If it was done for a failure to progress (unable to dilate or progress beyond a certain point), the success rate is less: 70% if labor failed to progress in the first stage of labor--before becoming fully dilated, versus 13% if progression stopped after you became fully dilated. Furthermore, if you decide you want to have a TOLAC, but then don't go into labor, success rates decrease further when an induction of labor is necessary. While keeping statistics in mind is important, we as midwives believe that the choices regarding labor and birth should be yours. We are dedicated to supporting you during these decisions, while providing compassionate and safe care.
If you do decide to have a TOLAC, we will continuously monitor your baby's heart rate during labor in order to pick up any fetal distress or sign of the uterine incision opening. We will also have IV access available and anesthesia and an OB/GYN attending available in the event that an immediate repeat cesarean is necessary.
The bottom line is that each person's situation is unique. If you are interested in a VBAC, ask your midwife about it! Having a conversation with your midwife early in your pregnancy is very important before deciding on a TOLAC versus a repeat cesarean section. Periodically throughout your pregnancy you should touch bases with your midwife about this decision, as well, in case anything has changed. The Midwives at Mount Auburn are supportive of helping women have successful VBACs and positive birth experiences.
