Hypercoagulability leading to placental thrombosis has been implicated in severe pregnancy complications. We compared the perinatal outcome in women with severe preeclampsia, intrauterine growth retardation (IUGR) and severe abruptio placentae and multiple acquired and inherited thrombophilias (study group, n=22) to matched women with similar complications and single thrombophilia (control group, n=22). Gestational age at delivery and birth weight were significantly lower in the study group compared to the control group (p<0.01) and among the study women with severe preeclampsia and IUGR. Severe pregnancy complications may occur earlier during pregnancy and more seriously affect perinatal outcome in women with multiple thrombophilias.