THE PREVALENCE OF LUPUS ANTICOAGULANT AND ANTICARDIOLIPIN ANTIBODIES IN WOMEN WITH A HISTORY OF FIRST TRIMESTER MISCARRIAGES

Objective To determine the prevalence of lupus anticoagulant and raise d anticardiolipin antibodies in women with a history of two or more mi scarriages in the first trimester of pregnancy. Design A prospective s tudy of lupus anticoagulant and anticardiolipin antibody levels in uns elected women with a history of two or more first trimester miscarriag es. Setting The prepregnancy clinic and miscarriage antenatal clinic i n a tertiary referral centre. Subjects Two hundred and forty-three wom en, of whom 113 (47%) had a past history of two miscarriages, and 130 (53%) had three or more miscarriages. Main outcome measures Quantitati ve detection of lupus anticoagulant and anticardiolipin antibodies; nu mber of miscarriages in women in the normal and the abnormal groups. R esults Of the 243 women tested, 41 (16.8%) had an abnormality of lupus anticoagulant or anticardiolipin antibodies. This was significantly d ifferent from the normal population as previously reported. Sixteen wo men (6.6%) were positive for lupus anticoagulant, 20 (8.2%) had elevat ed anticardiolipin antibodies, and five (2%) had both abnormalities. T he most frequently positive test for lupus anticoagulant was the dilut e Russel viper venom time, and IgG was the most frequently elevated an ticardiolipin antibody. Of the women with a history of only two miscar riages, 15% had an abnormality of lupus anticoagulant or anticardiolip in antibodies, compared with 185% of those with a history of three or more miscarriages. This did not reach statistical significance. There were 117 (48%) primary miscarriers and 126 (52%) secondary miscarriers . Of the primary miscarriers, 17% had an abnormality, compared to 18% of the secondary miscarriers. Conclusions These findings provide furth er evidence of an association between lupus anticoagulant and anticard iolipin antibodies and early pregnancy loss. It is not known if these are the cause of miscarriage, markers for miscarriage, or if antiphosp holipid antibodies develop as a result of a noncontinuing pregnancy. F urther studies comparing various treatments are required before women with these antibodies can be optimally managed.