Thrombophylaxis and bleeding complications after cesarean section.

OBJECTIVE: To evaluate the safety of different regimes of thromboprophylaxis with low molecular weight heparins (LMWHs) in women undergoing cesarean section.

DESIGN: Retrospective single-center cross-sectional study.

SETTING: University Medical Center, The Netherlands.

POPULATION: All women that delivered by cesarean section in the Erasmus Medical Center, Rotterdam, between January 2004 and December 2007 received thromboprophylaxis. We included women who received thromboprophylaxis according to the routine administration schedule at that time.

METHODS: Three different consecutive regimes of thromboprophylaxis were used. In the first period, women received dalteparin 5000IU pre- and postoperatively (group A), in the second period, nadroparin 5700IU was administered pre- and postoperatively (group B), and in the third period, nadroparin 2850IU was administered not earlier than 6-12 hours postoperatively (group C). Detailed information on individual characteristics, cesarean section and postpartum period were extracted from patient files.

MAIN OUTCOME MEASURES: Postoperative bleeding complications.

RESULTS: A total of 1527 women were eligible and included. In group B, significantly more women experienced bleeding complications (necessitating either conservative treatment or re-laparotomy) compared with the other two groups (19/574 women in group B vs. 9/647 in group A and 1/306 in group C). After adjusting for potential confounders (maternal age, body mass index, and occurrence of preeclampsia/hemolysis, elevated liver enzymes and low platelet count) these effects remained significant (p=0.005). The incidence of thromboembolism was not different in the three groups.

CONCLUSIONS: Different regimes of thromboprophylaxis in women with cesarean section influenced the occurrence of bleeding complications.