OBJECTIVE: To compare placental pathology between women with and without thrombophilia who had severe preeclampsia, intrauterine growth retardation, severe abruptio placentae, or stillbirth. METHODS: After delivery, 68 women with singleton pregnancies with one of the above complications were evaluated for an inherited thrombophilia: factor V Leiden, methylenetetrahydrofolate reductase and prothrombin gene mutation, and deficiencies of protein S, protein C, and antithrombin III. Thirty-two women were thrombophilic (group A), and 36 women were not (group B). There was no difference in maternal age, parity, and type of pregnancy complication. A single pathologist examined each placenta. RESULTS: The gestational age at delivery, birth weight, and placental weight were significantly lower in group A. Three parameters showed significant differences between the groups: thrombophilic women had a higher number of villous infarcts (P < .01), more multiple infarcts (P < .05), and a higher incidence of placentas with fibrinoid necrosis of decidual vessels (P < .05). CONCLUSION: Placentas of women with severe complications and thrombophilia have an increased rate of vascular lesions.