Objective: This study was undertaken to test the hypothesis of an association between pharmacologic agents used for labor induction, in particular dinoprostone, and postpartum disseminated intravascular coagulation (DIC).
Study design: A retrospective hospital-based case-control study. Adjusted odds ratios (AOR) were calculated by a conditional logistic regression.
Results: Forty valid cases of postpartum DIC were compared against 197 matched controls. Labor was induced in 17% of controls, and 56% of cases (AOR = 7.2; 95% CI: 2.1-24.6). The association was observed for both dinoprostone (AOR = 6.7; 95% CI: 1.7-26.5) and oxytocin (AOR = 8.4; 95% CI: 1.4-50.9). Other risk factors identified were as follows: a maternal age older than 34 years (AOR = 9.5; 95% CI: 2.4-37.7), complications during pregnancy (AOR = 5.5; 95% CI: 1.3-22.8), and a gestational age of over 40 weeks (AOR = 3.5; 95% CI: 1.1-11.1). Such factors were shown to also have an interaction with the induction of labor. Oxytocin augmentation showed a negative association (AOR = 0.1; 95% CI: 0.02-0.4). The absolute risk attributable to induction was estimated in 5 per 10,000 deliveries.
Conclusion: The pharmacologic induction of labor is associated with an increased risk of postpartum DIC, regardless the substance used. Although the absolute risk seems to be quite low, the obstetricians should not neglect it, in particular for the special risk groups identified.