Objective: To determine the type of recurrent pregnancy loss associated with antiphospholipid antibodies.
Methods: This was a retrospective analysis of women who had two or more pregnancy losses and who were tested for antiphospholipid antibodies. The specific type of pregnancy losses were determined in patients with and without antiphospholipid antibodies.
Results: In our highly selected referral population, 76 of 366 women (21%) tested positive for lupus anticoagulant or anticardiolipin antibodies of 20 or more immunoglobulin-G phospholipid antibody units. Pregnancy loss occurred in 280 of 333 (84%) prior pregnancies in women with and 1240 of 1479 (84%) without antiphospholipid antibodies. However, 50% of pregnancy losses in women with antiphospholipid antibodies were fetal deaths, compared with less than 15% in women who were antiphospholipid antibody-negative. More than 80% of women with antiphospholipid antibodies had at least one fetal death, compared with less than 25% of women without (P < .001). The specificity of fetal death for the presence of antiphospholipid antibodies in patients with recurrent pregnancy loss was 76%. In contrast, two or more early first-trimester losses without fetal death had a specificity of only 6% for antiphospholipid antibodies.
Conclusion: Fetal death is more characteristic of the type of loss experienced by patients with recurrent pregnancy loss than early first-trimester pregnancy loss in women with antiphospholipid antibodies.