Birth by Caesarean section and female offspring's risk of Caesarean section delivery

The objective of this study was to examine the association of birth by Caesarean section (CS) with female offspring's risk of CS delivery.

We used data from the 3G Multigenerational Cohort, which includes women whose births and their own subsequent pregnancies and deliveries were recorded in the population-based Nova Scotia Atlee Perinatal Database. The current analysis was limited to the women's first delivery (n = 23,605). Confounding variables were identified using a directed acyclic graph. The association between birth by CS and later CS delivery was examined with Poisson regression adjusted for confounding variables.

Seventeen percent of women were born via CS, and 23 % delivered by CS. Compared to women born vaginally, women born by CS had an adjusted relative risk (RR) of 1.36 (95 % confidence interval [CI] 1.30, 1.43) for delivering by CS. Restricting the sample to women born to nulliparous mothers did not change the association (RR 1.35), while restriction to women born out of low-risk pregnancies weakened it slightly (RR 1.25).

Birth by CS is associated with a 36 % increased risk of women delivering their first child by CS. This increase is likely due to shared medical and socio-cultural factors.