Women have lower rates of childbirth after a cesarean section. A new study suggests that this is not by choice, but appears to be an effect of the C-section itself.
Researchers followed 2,021 women after delivering their first babies, 599 of whom had C-sections. The women reported the number of months they had unprotected sex during the three years following the births. The study is in JAMA Network Open.
Of the women who delivered by C-section, 68.9 percent conceived, compared with 76.7 percent of women who delivered vaginally. C-section was also associated with a lower rate of subsequent birth — 42.8 percent, compared with 50.1 percent for vaginal delivery.
After controlling for maternal age, previous infertility, prior miscarriage and other variables, they found that compared with having delivered vaginally, a C-section delivery was associated with a 15 percent lower likelihood of a subsequent conception.
The reason for the lower likelihood of pregnancy after a C-section is not known, but the lead author, Kristen H. Kjerulff, a professor of public health at Pennsylvania State University, said that scarring of the inside of the uterus during the procedure and ensuing low-grade infection may be factors.
The authors note that the study had limits. Much of their data depended on self-reports, which can be unreliable, and the women were of higher socioeconomic status than the general population of women in Pennsylvania, where the study took place.