Vaginal birth after caesarean | |
---|---|
MeSH | D016064 |
In case of a previous Caesarean section a subsequent pregnancy can be planned beforehand to be delivered by either of the following two main methods:
Both have higher risks than a vaginal birth with no previous caesarean section. There are many issues which affect the decision for planned vaginal or planned abdominal delivery. There is a slightly higher risk for uterine rupture and perinatal death of the child with VBAC than ERCS, but the absolute increased risk of these complications is small, especially with only one previous low transverse caesarean section. 60–80% of women planning VBAC will achieve a successful vaginal delivery, although there are more risks to the mother and baby from an unplanned caesarean section than from an ERCS. Successful VBAC also reduces the risk of complications in future pregnancies than ERCS.
Where the woman is labouring with a previous section scar (i.e. a planned VBAC in labour), depending on the provider, special precautions may be recommended. These include intravenous access (a cannula into the vein)and continuous fetal monitoring (cardiotocography or CTG monitoring of the fetal heart rate with transducers on the mother's abdomen). Most women in the UK should be counselled to avoid induction of labour if there are no medical reasons for it, as the risks of uterine rupture of the previous scar are increased if the labour is induced. Other intrapartum management options, including analgesia/anesthesia, are identical to those of any labour and vaginal delivery.
For ERCS, the choice of skin incision should determined by what seems to be most beneficial for the present operation, regardless of the choice of the previous location as seen by its scar, although the vast majority of surgeons will incise through the previous scar to optimise the cosmetic result. Hypertrophic (very thick or unsightly) scars are best excised because it gives a better cosmetic result and is associated with improved wound healing. On the other hand, keloid scars should have their margins left without any incision because of risk of tissue reaction in the subsequent scar.
The choice of VBAC or ERCS depends on many issues: medical and obstetric indications, maternal choice and availability of provider and birth setting (hospital, birthing center, or home). Some commonly employed criteria include:
According to the American Pregnancy Association, 90% of women who have undergone caesarean deliveries are candidates for planned VBAC because there are no obvious antenatal reasons for them as individuals why planned ERCS is safer.