Effect of antiphospholipid antibodies in women undergoing in-vitro fertilization: role of heparin and aspirin.

To describe the prevalence of antiphospholipid antibodies in women undergoing in-vitro fertilization (IVF) and to determine if heparin and aspirin affect implantation rates, 191 women with a history of infertility undergoing IVF were prospectively tested for antiphospholipid antibodies. This was a two-centre, non-randomized comparison of women with positive antiphospholipid antibodies receiving heparin and aspirin versus standard treatment. An enzyme-linked immunosorbent assay, with referenced standards and known positive and negative sera on each plate, was utilized to measure antibodies to cardiolipin, phosphatidylinositol, phosphatidylglycerol, phosphatidylserine and phosphatidylethanolamine. Statistical analyses of results included analysis of variance and Fisher's two-tailed exact test. Antiphospholipid antibodies were detected in 18.8% of patients undergoing IVF compared with only 5.5% in the 200 normal controls, 26% in 200 women with recurrent pregnancy loss, and 32% in 200 women with systemic lupus erythematosus. In conclusion, antiphospholipid antibodies were found more frequently in women undergoing IVF than in the normal control population. Although implantation rates appeared higher in the group of women treated with heparin and aspirin, no statistically significant differences were detected in implantation, pregnancy and ongoing pregnancy rates between those who received standard therapy and those treated with heparin and aspirin.