Objective: We evaluated whether the production of prostacyclin and thromboxane by normal human placental tissue is consistently altered by incubation with immunoglobulin G fractions prepared from plasma of patients with lupus anticoagulant.
Study design: The immunoglobulin G fractions were prepared from eight patients with lupus anticoagulant and eight control patients. Doses of these fractions (3 mg, 7.5 mg, and 12 mg) were incubated with placental explants obtained from normal pregnancies, and prostacyclin and thromboxane production was assessed over 48 hours.
Results: Prostacyclin production was similar for placental tissue incubated with immunoglobulin fractions from control and lupus anticoagulant patients at all of the doses tested. Placental production of thromboxane was significantly increased with immunoglobulin fractions from lupus anticoagulant patients for all three doses (p = 0.02).
Conclusions: The immunoglobulin G fraction from patients with lupus anticoagulant consistently alters placental thromboxane production without affecting prostacyclin production. Increases in placental thromboxane production may contribute to antiphospholipid antibody-mediated pregnancy loss.