RELATIONSHIP BETWEEN LUPUS ANTICOAGULANT (LAC) AND PREGNANCY-INDUCED HYPERTENSION

Lupus anticoagulant (LAC), a serum antiphospholipid autoantibody, is b elieved to be one of the causes of infertility or fetal loss. The purp ose of the present study was to evaluate the role of LAC in the pathog enesis of hypertension during pregnancy. In this study, 20 pregnant wo men with hypertension were classified into two groups: 14 patients who did not have hypertension before the pregnancy but developed it durin g the pregnancy (pregnancy-induced hypertension; Group A) and 6 patien ts who had hypertensive or renal disease before the pregnancy, and dev eloped further hypertension during the pregnancy (pregnancy-aggravated hypertension; Group B). A LAC coagulation assay was performed, and th e presence of LAC in each group was compared. All 14 patients in group A were LAG-negative. In contrast, 3 of the 6 patients in group B were LAC-positive, and had clinical autoimmune diseases. The incidence of pregnancy-induced hypertension was also examined in 15 pregnancies fro m 9 LAC-positive women who had a history of repeated fetal loss but no systemic autoimmune disease (Group C). None of these 15 pregnancies h ad hypertensive complications, even when they reached term. In the pla centas of LAC-positive women, no characteristic changes other than fib rinoid degeneration and microscopic infarction were observed upon hist ological examination. These results suggest that LAC does not relate w ith the onset of hypertension during pregnancy.