Thrombophilic mutations are a main risk factor for placental abruption.

BACKGROUND AND OBJECTIVES The aim of the present study was to evaluate inherited thrombophilic factor V Leiden and factor II A20210 mutations in women presenting with abruption of a normally implanted placenta. DESIGN AND METHODS In a multi-center, case-control study, 50 consecutive women requiring immediate delivery because of abruption of the placenta were enrolled. Inclusion criteria were: abruptio placentae requiring immediate delivery, normally implanted placenta, Caucasian ethnic background, parity <3, delivery performed at Institutions. Exclusion criteria were: history of thromboembolism, history of 2 or more spontaneous abortions, uterine leiomyomas with a diameter >5 cm, illicit drug abuse, premature rupture of membranes, multiple pregnancy. One hundred Caucasian women with uneventful pregnancies carried to term, matched for parity and age, served as controls. RESULTS Heterozygotes were found to be significantly more prevalent among women with abruptio placentae than among controls. The carriership of the FV Leiden mutation confers a OR of 9.12 (95% C.I.: 2.18-31.7; p=0.0005). Women carrying F II A20210 mutation have a OR of 12.25 (95% C.I.: 2.36-29.6; p=0.0004). No homozygotes or double heterozygotes were found. Twenty-three patients (46%) also met the criteria for a diagnosis of pre-eclampsia (PE). In such cases the prevalence of mutations (factor V: 6 cases, 26.1%; factor II: 5 cases, 21.7%) was similar to that in women without pre-eclampsia (factor V: 5 cases, 18.7%; factor II: 5 cases, 18.5%). INTERPRETATION AND CONCLUSIONS The presence of either of the above reported thrombophilic mutations represents a relevant risk factor for the occurrence of placental abruption in Caucasians. This risk is independent of the development of pre-eclampsia. Patients who have had dramatic abruption of a normally implanted placenta should undergo evaluation for the presence of genetic mutations of coagulation factors V and II.