Mild thrombocytopenia and the risk for postpartum hemorrhage in twin pregnancies.

Objective: We aimed to investigate the association of mild thrombocytopenia with postpartum hemorrhage (PPH) and blood transfusion among women with twin gestations.

Methods: A retrospective cohort study (Jan 2015 to May 2019) was performed. Women with twin pregnancies and pre-delivery mild thrombocytopenia were compared to those with normal platelet count. The primary outcome was the rate of PPH, defined as a composite of one or more of the following: (1) need for packed red blood cell transfusion; (2) postpartum hemoglobin decline of ≥3 g/dL; and (3) the use of postpartum uterotonics agents in addition to oxytocin.

Results: Of 1085 women who were included in final analysis, 315 (30.9%) had mild thrombocytopenia (and 770 (69.1%) served as controls. The rate of PPH was increased in the study group (14% vs. 9.4%, P = 0.03), as was the use of uterotonic agents (3.8% vs. 1.3%, respectively, P = 0.02). The rate of blood product transfusion and hemoglobin decline >3 g/dL was not significantly different between the groups. In multivariate logistic regression analysis, mild thrombocytopenia was associated with a higher risk for PPH (OR 1.55 [95% CI 1.02-2.35], P = 0.02).

Conclusion: Mild thrombocytopenia in twin pregnancies is associated with an increased risk of interventions such as the use of uterotonic agents.