The risks linked to caesarean births (whether chosen by the woman or her clinicians) are higher, regardless of variables such as demographics, medical and pregnancy history, gestational age of the foetus, pregnancy complications, where the baby is born and the skills of those helping to deliver the baby.
Researchers randomly selected eight Latin American countries and from those, 120 also randomly selected health facilities provided complete data on 97,307 deliveries of babies during a three-month study period. These data came from the Latin American component of the WHO Global Survey on Maternal and Perinatal Health, specifically carried out for this study in 2005.
They wanted to compare the risks and benefits of caesarean delivery compared to vaginal delivery. Of the 97,307 cases, 33.7 percent were caesarean and 66.3 percent vaginal. Overall, perinatal outcomes were good in these 120 hospitals, not far from those in developed countries.
They found that a woman having a caesarean delivery had twice the risk of illness and mortality (including death, hysterectomy, blood transfusion and admission to intensive care) as a woman having a vaginal delivery.
There was a five times higher risk of having to have antibiotic treatment after birth for women who had a caesarean delivery (elective or decided by clinicians) than those who had a vaginal delivery.
Risk of having to stay in a neonatal intensive care unit for newborn babies who were born head-first was doubled after a caesarean delivery compared to a vaginal birth.
The authors also found that the risk of neonatal death was also significantly increased (more than 70 percent higher) up to hospital discharge for babies who were born head first from both an elective and a clinician chosen caesarean delivery, compared to a vaginal delivery.
However, caesarean delivery had a large protective effect in preventing foetal deaths in cases of breech born babies and reduced overall risks in those cases.
The authors conclude that there are no net benefits from the very liberal use of caesarean delivery on maternal and neonatal outcomes, both at the institutional or individual level, and it can do harm. The exceptions are fewer postpartum severe vaginal complications, and better foetal outcomes among breech presentations.
An accompanying editorial says that more accurate estimates of probabilities from other populations are needed to support informed childbirth choices.