Maternal predictive factors for fetal congenital heart block in pregnant mothers positive for anti-SS-A antibodies.

OBJECTIVE

To determine the maternal predictive factors for fetal congenital heart block (CHB) in pregnancy in mothers positive for anti-SS-A antibodies.

METHODS

The Research Team for Surveillance of Autoantibody-Exposed Fetuses and Treatment of Neonatal Lupus Erythematosus, the Research Program of the Japan Ministry of Health, Labor and Welfare, performed a national survey on pregnancy of mothers positive for anti-SS-A antibodies. We analyzed 635 pregnant mothers who tested positive for anti-SS-A antibodies before conception but had no previous history of fetal CHB. We performed univariate and multivariate analysis (models 1, 2, and 3 using different set of independent variables) investigated the relation between risk of fetal CHB and maternal clinical features.

RESULTS

Of the 635 pregnant mothers, fetal CHB was detected in 16. Univariate analysis showed that fetal CHB associated with use of corticosteroids before conception (OR 3.72, p = 0.04), and negatively with use of corticosteroids (equivalent doses of prednisolone (PSL), at ≥10 mg/day) after conception before 16-week gestation (OR 0.17, p = 0.03). In multivariate analysis, model 1 identified the use of corticosteroids before conception (OR 4.28, p = 0.04) and high titer of anti-SS-A antibodies (OR 3.58, p = 0.02) as independent and significant risk factors, and model 3 identified use of corticosteroids (equivalent doses of PSL, at ≥10 mg/day) after conception before 16-week gestation as independent protective factor against the development of fetal CHB (OR 0.16, p = 0.03). Other maternal clinical features did not influence the development of fetal CHB.

CONCLUSION

The results identified high titers of anti-SS-A antibodies and use of corticosteroids before conception as independent risk factors, and use of corticosteroids (equivalent doses of PSL, at ≥10 mg/day) after conception before 16-week gestation as an independent protective factor for fetal CHB.