Thrombophilia is common in women with idiopathic pregnancy loss and is associated with late pregnancy wastage.

OBJECTIVE

To describe the characteristics of thrombophilia in women with idiopathic pregnancy loss.

DESIGN

Prospective observational study.

SETTING

Tertiary referral center in a teaching academic hospital.

PATIENT(S): One hundred forty-five patients with repeated pregnancy loss and 145 matched controls.

INTERVENTION(S): Prospective assessment of thrombophilia in patients and controls.

MAIN OUTCOME MEASURE(S): Prevalence of activated protein C (APC) resistance, protein C, protein S, and antithrombin III deficiencies, antiphospholipid antibodies, factor V Leiden, factor II G20210A, and MTHFR C677T mutations.

RESULT(S): At least one thrombophilic defect was found in 66% of study group patients compared with 28% in control group patients. Combined thrombophilic defects were documented in 21% of women with pregnancy loss compared with 5.5% of control patients. Late pregnancy wastage occurred more frequently in women with thrombophilia compared with women without thrombophilia (160/429 [37%] vs. 39/162 [24%], respectively). APC resistance was documented in 39% of women with pregnancy loss compared with 3% of the control patients. APC resistance without factor V Leiden mutation was documented in 18% of women with pregnancy loss compared with none of the controls. While factor V Leiden mutation was more common in women with pregnancy loss (25% vs. 7.6%), factor II G20210A and homozygosity for MTHFR C677T contributed to pregnancy loss only in the presence of other thrombophilia.

CONCLUSION(S): Thrombophilia was found in the majority (66%) of women with idiopathic pregnancy loss. APC resistance with or without factor V Leiden mutation is the most common thrombophilic defect, and combined thrombophilia is a frequent finding in women with pregnancy loss. Thrombophilia is associated with increased frequency of late pregnancy wastage.