Anticardiolipin and antinuclear antibodies in patients with unexplained recurrent abortions

In a controlled study on a resident population in Kuwait, 103 patients with unexplained recurrent spontaneous abortions were investigated for the frequency of positive tests for anticardiolipin antiobodies (ACA) and antinuclear antibodies (ANA). The frequency of ACA was significantly (P<0.001) higher in patients (32.0%) than in controls (7.1%). Only four patients (3.8%) were positive for both IgG and IgM ACA. The frequency of positive tests for ANA was also significantly (P<0.001) higher in patients (13.6%) than in controls (1.2%). No difference was found between first and second trimester aborters in the frequency of positive tests for either ACA or ANA. Primary aborters did not differ from secondary aborters in the frequency of ACA. However, secondary aborters had significantly higher frequency of ANA. There was no concordance between ACA and ANAN positive tests. These results suggest that ACA may be associated with some cases of unexplained recurrent abortions and that tests for both IgG and IgM isotypes should be carried out in the investigations of these patients.