Administration of low molecular weight heparin within two hours before caesarean section increases the risk of wound haematoma

A retrospective analysis of the relation between time interval from prophylactic administration of low molecular weight heparin (LMWH) to delivery and the occurrence of wound haematoma was performed in all women, who had a caesarean section in 1998. After administration of LMWH within 2 hours of surgery, the percentage of women with a wound haematoma was significantly larger (12% vs 3%). Multivariate regression analysis, including other risk factors for wound haematoma, indicated administration of LMWH within 2 hours prior to delivery as the only statistically significant factor, which influenced the development of wound haematoma (odds ratio = 5.3, 95% CI = 1.2-22.8)