Antiphospholipid antibodies and infertility: fact or fallacy.

Some clinicians are convinced that antiphospholipid antibodies, including antibodies to any one of five-to-seven phospholipid antigens, are associated with infertility. Additionally, some clinicians recommend that infertile women who have antiphospholipid antibodies and are undergoing in-vitro fertilization should be treated with heparin to improve the rate of pregnancy. However, experts disagree regarding the relationship between antiphospholipid antibodies and infertility. There is also substantial evidence that treatment with heparin does not alter the rate of pregnancy following in-vitro fertilization. Why the confusion? Probable culprits include variation in study design and the selection of infertile patients. Another important problem is that assays for antiphospholipid antibodies other than anticardiolipin are not standardized. Before the real relationship between antiphospholipid antibodies and infertility is discovered, assays for antiphospholipid antibodies other than anticardiolipin must be standardized and properly designed studies conducted. Randomized, controlled trials must be done to determine if heparin should be recommended as an adjunctive treatment for in-vitro fertilization in women with antiphospholipid antibodies.