To estimate the association between delivery preferences during pregnancy and actual delivery mode.
This was a prospective cohort study using data from the Norwegian Mother and Child Cohort Study (N=65,959). We analyzed predictors of birth outcome by means of women's preferences for mode or delivery and a range of medical and socioeconomic factors with multivariable logistic regression models. The term "elective" cesarean delivery includes cesarean deliveries planned 8 hours or more before delivery and performed as planned.
When asked about delivery preference at 30 weeks of gestation, 5% of the women reported a preference for a cesarean delivery, 84% had a preference for vaginal delivery, and 11% were neutral. Among those with a cesarean delivery preference, 48% subsequently had a cesarean delivery (12% acute and 36% elective), and of those with a vaginal preference 12% delivered by cesarean (8.7% acute and 3.1% elective). When adjusting for maternal characteristics and medical indications, the odds for an acute cesarean delivery among nulliparous women with a cesarean delivery preference was almost two times higher (odds ratio [OR] 1.97, 95% confidence interval [CI] 1.49-2.62) and for elective cesarean delivery the preference was 12 times higher (OR 12.61, 95% CI 9.69-16.42) than for women with a vaginal preference. For multiparous women, the corresponding figures were OR 3.13 (95% CI 1.39-7.05) and OR 10.04 (95% CI 4.59-21.99). When multiparous women with previous cesarean deliveries were excluded, the OR for an elective cesarean delivery was 26 times higher given a cesarean delivery preference compared with a vaginal delivery preference (OR 25.78, 95% CI 7.89-84.28). Based on a small subset of women with planned cesarean delivery on maternal request (n=560), we estimated a predicted probability of 16% for nulliparous women (25% for multiparous women) for such cesarean delivery.
Pregnant women's expressed preferences for delivery mode were associated with both elective and acute cesarean deliveries.