Prevalence of antiphospholipid antibodies in patients with fetal loss.

The prevalence of antiphospholipid and antinuclear antibodies in 102 patients with at least three unexplained miscarriages before a gestational age of 12 weeks, or at least one intrauterine fetal death after 12 weeks, was investigated and compared with the prevalence in 102 normal pregnant controls. Six patients had a history of thrombosis and six had 'lupus-like' disease. Twenty one patients had anticardiolipin antibodies compared with 10 controls. Serum samples of nine patients and one control contained antinuclear antibodies. The lupus anticoagulant was present in the plasma of five patients with anticardiolipin antibodies. The influence of patient selection on the results was illustrated by the finding that antiphospholipid antibodies and antinuclear antibodies were mainly detected in patients with lupus-like disease or a history of thrombosis. When these patients were excluded there was no significant difference in the prevalence of anticardiolipin and antinuclear antibodies between patients and controls. Therefore, in the absence of lupus-like disease or a history of thrombosis, screening for antiphospholipid antibodies in patients with adverse pregnancy outcomes seems not to be indicated.