Prevalence of antiphospholipid antibodies among women experiencing unexplained infertility and recurrent implantation failure

The prevalences of antiphospholipid antibodies (APAs) among 1,325 women with a history of unexplained infertility and 676 women experiencing recurrent implantation failure were compared with 789 women experiencing recurrent pregnancy loss and 205 fertile control women. Eight percent and 9% of women with a history of unexplained infertility and recurrent implantation failure had more than one positive APA compared with 1.5% of fertile negative control women and 11% of positive control women experiencing recurrent pregnancy loss.