Vaginal Birth After Cesarean Section (VBAC)
25 - 29% of babies born in the United States are born by Cesarean Section. Doctors once thought a woman who delivered by cesarean section always had to deliver by cesarean section. That is no longer true. Doctors now realize a woman who delivered previously by cesarean section can safely try to deliver her baby vaginally. In fact, 90% of patients with one previous cesarean section will be candidates to deliver vaginally. Of woman who try to deliver vaginally after they have had a cesarean section, 60 - 80% will be successful. A cesarean section can be performed if a woman tries to deliver vaginally and certain circumstances occur.
Potential Benefits of VBAC
- Avoids abdominal surgery
- Less pain
- Less risk of infection
- Lower blood loss
- Shorter hospital stay
- Faster recovery
- Easier to move (mobilize) after delivery
Risks of VBAC
- Rupture of previous uterine scar
- Rupture of Uterus
- Loss of oxygen delivered to the baby
- Increased risk of infection (if cesarean section performed)
Potential Benefits of Repeat Cesarean Section
- Avoids risks of VBAC
- Allows for scheduled cesarean section
- Generally less traumatic and easier recovery than attempted labor followed by cesarean section
Factors to Consider
Type of previous cesarean section. When deciding if you should try a VBAC, the most important factor to consider is the type of cesarean section you had. A vertical (classical) cesarean section runs up and down from just above the bladder toward the top of the uterus. A low transverse cesarean section runs from side to side in the lower uterus. Scars from a prior vertical (classical) cesarean section are more likely to rupture than scars from a prior low transverse cesarean section. Uterine rupture is not common (0.5 - 1.5 % of VBAC), but it can lead to hemorrhage in the mother and a lack of oxygen in the baby. It is not possible to tell what kind of uterine incision was performed by the scar on your abdomen. Therefore, it is important for you and your doctor to document the type of cesarean section you had. This is done by obtaining a copy of your prior physician's operative note.
Placenta Previa. The placenta covers the opening of cervix. The placenta will separate from the uterus when the cervix dilates. This will cause the mother to hemorrhage.
Abruptio Placenta. The placenta separates from the wall of the uterus before the baby delivers. This will lead to a lack of oxygen for the baby.
Problems with the baby. Extremely large babies, babies not growing like they should, babies in a breech or transverse position and babies with certain birth defects are probably best delivered by a repeat cesarean section.
Cephalopelvic Disproportion (CPD). This refers to the relationship of the baby (size and position) with the mother's pelvis (size and shape). In some circumstances a VBAC would be an appropriate choice. For example, this baby is smaller and your pelvis appears to be adequate. In other circumstances a repeat cesarean section would make more sense. For example, this baby is larger and your pelvis appears to be small.
A medical condition you may have or that you may develop. Patients with some medical conditions do better with a vaginal delivery while other medical conditions are best managed by a repeat cesarean section.
Pain control. The indications for pain relief are the same with a VBAC as with any vaginal delivery. IV medications and epidurals can be safely used for pain relief in most circumstances.
VBAC may be a successful and rewarding option for you. However, it is important to remember that every patient is different, every delivery is different, and no delivery is risk free. You need to be aware of the risks involved and the potential benefits when making your decision and you should thoroughly discuss all of these factors with your physician.