Vaginal Birth After Caesarean - Drawbacks and Benefits

Drawbacks and Benefits

A caesarean section leaves a scar in the wall of the uterus which is considered weaker than the normal uterine wall. During labor in a subsequent pregnancy, there is a small risk of a ruptured uterus (0.47% chance among women having a trial of labor after cesarean section versus 0.03% among women scheduling repeat caesarean deliveries). If a uterine rupture does occur, the risk of perinatal death is approximately 6%. Mothers with a previous 'bikini cut' or lower uterine segment caesarian are considered the best candidates, as that region of the uterus is under less physical stress during labor and delivery. Aside from uterine rupture risk, the drawbacks of VBAC are usually minor and identical to those of any vaginal delivery, including the risk of perineal tearing. Maternal morbidity, NICU admissions, length of hospital stay, and medical costs are typically reduced following a VBAC rather than a repeat caesarean delivery.

The risk of post-operative infection doubles if vaginal delivery is attempted but results in another caesarean. All complications of caesarean section are more likely and more severe if it is done as an emergency after a failed attempt at vaginal delivery rather than as a planned operation.

Repeat caesarean sections become increasingly complicated with each subsequent operation, as the probability of internal abdominal adhesions, bladder injuries, and abnormal placentation (placenta praevia or placenta accreta) increases dramatically, with placenta accreta reportedly affecting 50-67% of women having three or more caesarean sections. According to the United States Agency for Healthcare Research and Quality, "Abnormal placentation has been associated with both maternal and neonatal morbidity including need for antepartum hospitalization, preterm delivery, emergent caesarean delivery, hysterectomy, blood transfusion, surgical injury, intensive care unit (ICU) stay, and fetal and maternal death and may be life-threatening for mother and baby."