Pregnancy outcome. Influence of antiphospholipid antibody titer, prior pregnancy losses and treatment.

OBJECTIVE

To evaluate the effectiveness of combination therapy in preventing fetal loss in women with circulating antiphospholipid antibodies and a previous history of adverse pregnancy outcomes.

STUDY DESIGN

We identified 18 pregnant women with antiphospholipid antibodies who had a total of 59 prior pregnancies. Of these pregnancies, spontaneous first-trimester abortions occurred in 36 (61.0%); fetal demise after the first trimester occurred in 9 (15.2%); voluntary terminations were elected in seven (11.9%) pregnancies; and there were seven (11.9%) surviving infants. During their next pregnancies, these patients were treated with prednisone and/or low-dose aspirin.

RESULTS

Fourteen patients delivered successfully between 33 and 39 weeks' gestation, resulting in a live birth rate of 77.8% and a pregnancy loss rate of 22.2%. We also observed an association between the number of prior fetal losses, the anticardiolipin antibody titer and the fetal survival rate following therapy. Two or more prior fetal losses and high autoantibody titer resulted in a fetal survival rate of 50-75% with varying therapeutic regimens and dosages. However, an improved fetal survival rate of 75-100% was observed with less than two prior fetal losses and low-mid anticardiolipin antibody titer with the same therapy.

CONCLUSION

Therefore, the results of this study suggest that although pharmacologic prophylaxis improves the outcome of pregnancies complicated by circulating antiphospholipid antibodies, such an outcome is influenced by the number of prior fetal losses and the anticardiolipin antibody titer.