Thromboprophylaxis in pregnant women with thrombophilia and a history of thrombosis.

Background Despite intensive research, thromboembolism still accounts for significant maternal morbidity and mortality. We examined thrombophilia in patients with thromboembolism during pregnancy and evaluated the efficiency of antithrombotic prophylaxis in patients with thrombophilia for the prevention of recurrent thromboembolism. Materials and methods Sixty-eight women with a history of thromboembolism were managed during pregnancy, in light of their thrombotic history and the result of thrombophilia assessment. Group I (n=50) received prophylaxis with low molecular weight heparin (LMWH)±aspirin (50-100 mg/day) in preconception period or from the 1st trimester, during pregnancy and at least 6 weeks postpartum. Group II (n=18) received LMWH±aspirin from the II to III trimester. Results Thromboses were associated with pregnancy in 27 patients (39.7%), with systemic diseases - in nine (13.2%), oral contraceptives use - 22 (32.3%), immobilization due to surgery and/or trauma, long flight - six (8.9%), septic complications - two (2.9%). Nevertheless, 24.5% of patients had no apparent provoking factor for the development of thrombotic complications. Thirty-seven (54%) patients with venous thromboembolism (VTE) had familial history of VTE, and 25 (36.7%) had personal history of pregnancy complications (fetal loss syndrome, preeclampsia and placental abruption) (P<0.05 vs. control). Thrombophilia was detected in 58 (85.3%). Usual thrombogenic polymorphisms [factor V (FV) Leiden and prothrombin G20210A, heterozygous forms] were revealed in 16 (23.5%) and eight (11.7%) patients, respectively. Antiphospholipid antibodies (aPL) circulation was found in 34 (50%) patients. Non-usual thrombogenic polymorphisms were identified in 44 (64.7%) of the women and hyperhomocysteinemia - in 30 (44.2%). In group I no one had severe obstetric complications. All the patients were delivered at term and all the babies were alive. In group II moderate-to-severe obstetric complications were noted: preeclampsia - in 11 (16.2%), severe preeclampsia - seven (10.3%), preterm delivery - in 18 (26.4%) patients from subgroup II (P<0.05). Conclusions Women with a personal or a family history of thromboembolism and obstetric complications should be screened for thrombophilia. Beginning anticoagulant therapy early in such patients is effective not only for preventing recurring thrombosis but also preventing obstetric complications. Late prophylaxis after the completion of the trophoblast invasion therapy is much less effective.