A prospective study on the occurrence of autoantibodies in low-risk pregnancies

OBJECTIVE: This investigation was done to study the prevalence of anti-nuclear antibodies (ANA), anti-cardiolipin antibodies (aCL), and rheumatoid factor (RF), in presumed healthy women during their pregnancies. STUDY DESIGN: During an 18 month period blood samples were taken in the first, second and third trimester from 1200 pregnant women, representing a low-risk population. Clinical data on the pregnancy outcome were obtained by birth statistics after their deliveries. The diagnoses of preeclampsia, intrauterine growth retardation, fetal death, or abruptio placentae were stated in 57 of these women. An age- and parity-matched control group of 207 women with normal pregnancy outcome was drawn from the same low-risk population (n= 1200). A nonpregnant control group consisted of 157 women. The prevalence of ANA (immunofluorescence microscopy on HEp-2 cells), aCL-immunoglobulin G (enzyme-linked immunosorbent assay), and RF (latex agglutination test) in preeclampsia, intrauterine growth retardation, fetal death, or abruptio placentae were compared to the normal pregnancies, and to the nonpregnant controls. RESULTS: ANA occurred significantly more often (P<0.05) in pregnancies complicated by preeclampsia when compared to normal pregnancies. aCL occurred sparsely in normal as well as complicated pregnancies. RF was infrequently seen among all women in this study. CONCLUSION: An association was noted between the occurrence of ANA and preeclampsia. However, this association was too insensitive to use as a clinical tool.