The researchers said that cesarean deliveries appear to cause an overall 80% increased risk of severe maternal complications when compared with vaginal delivery.
For women 35 or older, the risk from C-section is nearly triple that of normal delivery, and that risk leaps to fivefold if they undergo a C-section before labor has commenced, the investigators found.
For women younger than 35, there was about a 50% higher risk of severe complications.
“Cesarean can save lives in some situations. However, it is not a trivial procedure,” said senior researcher Dr. Catherine Deneux-Tharaux, a research director with the Center for Epidemiology and Statistics at the Sorbonne in Paris. “It, in itself, carries risks of severe complications for the mother, mainly heavy bleeding, and should only be chosen as the delivery route when the risk-benefit balance has been discussed with the doctor.”
C-section rates have soared over the past two decades in most developed countries, where more than one in every five women deliver by cesarean, the study authors said in background notes.
To see what risks these operations might pose to the mother, Deneux-Tharaux and her colleagues compared 1,444 women who experienced severe complications after delivery with 3,464 women who did not.
The proportion of C-section deliveries was twice as high among the women who experienced severe complications, compared with the healthy “control” group (36% versus 18%).
The increased risk of complications associated with C-sections remained even after the researchers took into account other factors that influence maternal health, and after they excluded women with pre-existing health conditions that could lead to complications.
Birth by C-section “carries risk of severe complications for the mother, both at short-term and for the next pregnancy,” Deneux-Tharaux said. “In consequence, the mode of delivery should always be fully discussed by the women with the obstetrician or midwife, in order to avoid unnecessary procedures that carry risk.”