Failure to progress, or “dystocia” accounts for close to 30% of all cesareans. When the cervix won’t dilate or if it slows down or stops altogether at some point and labor is taking longer than average, a cesarean may be suggested. Also, prolonged labor may be caused by the baby not descending or contractions that aren’t strong enough, even after an attempted augmentation with cervical ripening agents or Pitocin.
If the baby’s head is too large to fit through the pelvis (which is often called cephalopelvic disproportion or “CPD”), either because the mother is too small or the baby is too big, a cesarean may be necessary. Sometimes a woman has a deformed pelvis because of a birth defect or a debilitating disease such as rickets or polio, which makes a vaginal delivery incredibly difficult or impossible.
A cesarean may be necessary if certain maternal health conditions are present. Toxemia, high blood pressure, gestational diabetes (which can lead to an extra large-sized baby), pre-eclampsia, heart or pulmonary disease, HIV infection, obstruction of the birth canal by fibroids and active genital herpes lesions are all possible indicators that a cesarean may need to take place, but not in all situations. Maternal exhaustion accounts for a small number of cesareans.
Problems with the baby such as genetic deformity, neural tube defects, hydrocephalus or heart problems can lead to a cesarean. Some babies may not survive the process of labor and vaginal birth. Also, multiple births run a higher risk of complications if a vaginal delivery is attempted. Cesareans are routinely performed with the delivery of twins, triplets (or more), since giving birth to multiples poses unique challenges. Multiples are much more common now, as a result of fertility treatments, which also contributes partially to the increase in the overall cesarean rates.
Close to a third of all cesareans are repeat cesareans, although more and more women are electing to try VBAC (vaginal birth after cesarean). On the other hand, many hospitals and doctors are choosing not to offer VBACs any longer.
The reason for the high number of repeat cesareans is partly because of the concern for a possible uterine rupture. Pre-planned or “elective” cesareans (for non-medical reasons) are becoming increasingly popular. The reason for this jump is mainly simply for convenience purposes (for the doctor, as well as the mother).