Prevalence of Thrombophilia in Women with Spontaneous Pregnancy Loss.

We retrospectively analyzed the records of 145 female patients ages 18 to 50 who were referred to the Thrombosis and Hemostasis Section of the Hematology-Oncology Division at Mt. Sinai Hospital from January 2000 to June 2004 for evaluation of thrombophilia as the etiology of pregnancy loss (PL).

Recurrent Pregnancy Loss (RPL) was defined as 2 or more PL in the first trimester of gestation. Women with one or more PL in the second and/or third trimester of gestation or stillbirth, or a combination of above were also analyzed.

The following thrombophilic conditions were evaluated: factor V Leiden, prothrombin gene mutation (G20210), antiphospholipid (APL) antibodies and lupus anticoagulant (LAC), homocysteine and functional levels of protein C, S and antithrombin.

Of the 145 patients, 20 were excluded from analysis for the following reasons: isolated 1 first trimester PL (15 patients), no verification of antiphospholipid antibodies (4 patients) and insuficient data (1 patient).

Of the evaluable patients, 75 (60%) had 2 or more first trimester PL, 14 (11.2%) patients had 1 or more second trimester PL, 2 (1.6%) patients had 1 or more third trimester PL and 24 (19.2%) patients had PL in different trimesters.

70 of the 125 patients (56%) were found to have a thrombophilic condition: 25 had antiphospholipid antibodies, 21 had factor V Leiden (20 heterozygous and 1 homozygous), 16 had prothrombin gene mutation (all heterozygous), 5 had protein S deficiency, 2 had homocysteine level, and 1 had protein C deficiency. We did not identify any patient with antithrombin deficiency.

Of the 75 patients with first trimester PL, 36 (48%) were found to have a thrombophilic condition: 18 (50%) had antiphospholipid antibodies, 9 (25) had factor V Leiden (1 homozygous and 8 heterozygous) (17%), 5 (13.8) had heterozygous prothrombin gene mutation (8%), 3 (8.3%) had increased homocysteine level and 3 had a low protein S level (8.3%).

In summary, we found a thrombophilic condition associated with PL in 56% in this patient population. The majority of patients had recurrent first trimester PL. The most prevalent thrombophilic disorder was the presence of antiphospholipid antibodies, followed by factor V Leiden, prothrombin gene mutation and protein S deficiency and the least common was increased homocysteine level. These results suggest that testing for thrombophilia may be warranted in women with recurrent PL.