Maternal Lyme disease and congenital heart disease: A case-control study in an endemic area.

OBJECTIVE

The purpose of this study was to determine whether maternal Lyme disease increases the risk of congenital heart defect.

STUDY DESIGN

This retrospective case-control study was carried out at a medical center in a suburban area where Lyme disease is endemic. Case patients comprised 796 children with a diagnosis of congenital cardiac anomaly. Control subjects comprised 704 children without cardiac defects selected from the records of the same pediatric cardiology service. Maternal histories were obtained through a mailed questionnaire survey. Unconditional logistic regression analyses examined the relationship between a history of preconception and prenatal clinical Lyme disease or tick bite and case or control status.

RESULTS

There was no association between congenital heart defect and maternal tick bite (adjusted odds ratio 1.1, 95% confidence interval 0.5-2.5) or maternal Lyme disease within 3 months of conception or during pregnancy (adjusted odds ratio 0.9; 95% confidence interval 0.2-3.6).

CONCLUSION

A woman who has been bitten by a tick or is treated for Lyme disease during or before pregnancy is not at increased risk for giving birth to a child with a congenital heart defect.