Objective: To investigate the role of autoimmune factors as a possible cause for implantation failure as manifested by chemical pregnancy after IVF and ET.
Design: Anticardiolipin, anti-double-stranded DNA (dsDNA), antinuclear antibody, lupus anticoagulant, and rheumatoid factor serum levels were examined in patients with chemical pregnancies and in matched controls.
Setting: An IVF unit, university-based IVF program.
Patients: The study group included 21 patients who had one or more chemical pregnancies and no deliveries. The control group consisted of 21 patients who had conceived and delivered after IVF-ET treatment, without any history of fetal wastage, matched for age, type and duration of infertility, and number of previous IVF cycles.
Results: The incidence of circulating autoimmune antibodies in the study group was 33.3% (7/21). Three patients (14.2%) were positive for anticardiolipin, two (9.5%) were positive for antidsDNA, one (4.7%) for antinuclear factor, and one (4.7%) for rheumatoid factor. Autoimmune antibodies were not detected in any of the control group.
Conclusion: Autoimmunity may play a role in implantation failure in IVF-ET. Circulating autoimmune antibody screening is therefore recommended after chemical pregnancy.