ObjectiveLabor induction is an increasingly common procedure, even among women at low risk, although evidence to assess its risks remains sparse. Our objective was to assess the association between induction of labor and postpartum hemorrhage (PPH) in low-risk parturients, globally and according to its indications and methods.MethodPopulation-based case-control study of low-risk women who gave birth in 106 French maternity units between December 2004 and November 2006, including 4450 women with PPH, 1125 of them severe, and 1744 controls. Indications for labor induction were standard or non-standard, according to national guidelines. Induction methods were oxytocin or prostaglandins. Multilevel multivariable logistic regression modelling was used to test the independent association between induction and PPH, quantified as odds ratios.ResultsAfter adjustment for all potential confounders, labor induction was associated with a significantly higher risk of PPH (adjusted odds ratio, AOR1.22, 95%CI 1.04–1.42). This excess risk was found for induction with both oxytocin (AOR 1.52, 95%CI 1.19–1.93 for all and 1.57, 95%CI 1.11–2.20 for severe PPH) and prostaglandins (AOR 1.21, 95%CI 0.97–1.51 for all and 1.42, 95%CI 1.04–1.94 for severe PPH). Standard indicated induction was significantly associated with PPH (AOR1.28, 95%CI 1.06–1.55) while no significant association was found for non-standard indicated inductions.ConclusionEven in low risk women, induction of labor, regardless of the method used, is associated with a higher risk of PPH than spontaneous labor. However, there was no excess risk of PPH in women who underwent induction of labor for non-standard indications. This raises the hypothesis that the higher risk of PPH associated with labor induction may be limited to unfavorable obstetrical situations.

Objective Caesarean rate increased in France between 1995 and 2003, but remained stable between 2003 and 2010. Our objective was to analyse these trends by identifying the groups of women who contributed to the increase and those who contributed to the stabilisation.Design Cross-sectional population-based study from the French national perinatal surveys.Setting All maternity units in France.Population Representative samples of women delivering in 1995 (n = 13 147), 2003 (n = 14 482), and 2010 (n = 14 681).Methods Robson classification, based on pregnancy and delivery characteristics, was used for each group. Results Overall caesarean rates were 15.4% in 199515.4% in , 19.7% in 200315.4% in and 20.5% in 201015.4% in . Between 199515.4% in and 2003, the contribution to the overall caesarean rate of all groups but one rose. Between 2003 and 2010, the contribution of all groups but three stabilised or decreased: nulliparous women in spontaneous labour with singleton cephalic fetuses at term (D = + 0.5%, 95% CI 0.1-0.9%), an increase explained by their higher caesarean rate; nulliparous women with induced labour at term (D = + 1.1%, 95% CI 0.8-1.4%) caused by an increase in both the caesarean rate and the relative size of this group; and women with previous caesarean (D = + 0.8%, 95% CI 0.3-1.3%), because of the growing size of this group.Conclusion Proposing and evaluating interventions for improving the management of labour in nulliparous women could help to maintain caesarean rates and mitigate increases among multiparous women in the future.

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