Maternal exposure to hydroxychloroquine and birth defects.

Area of Science:

• Obstetrics and Gynecology
• Teratology
• Rheumatology

Background:

• Hydroxychloroquine is a common treatment for rheumatic diseases and generally considered safe during pregnancy.
• Recent interest has grown due to its investigation as a potential treatment for coronavirus disease 2019 (COVID-19).
• Limited data exists on the specific risks of birth defects associated with hydroxychloroquine use during pregnancy.

Purpose of the Study:

• To investigate the association between hydroxychloroquine use during pregnancy and the occurrence of specific major birth defects in offspring.
• To analyze self-reported hydroxychloroquine exposure in pregnant women from two large case-control studies.

Main Methods:

• Utilized data from the National Birth Defects Prevention Study and the Slone Epidemiology Center Birth Defects Study.
• Employed a case-control design, comparing infants with major birth defects (cases) to healthy live-born infants (controls).
• Analyzed self-reported medication use, including hydroxychloroquine, from early pregnancy through delivery.

Main Results:

• Hydroxychloroquine use was reported by a small percentage of mothers in both case and control groups across both studies (0.04%-0.06%).
• Women reporting hydroxychloroquine use often had complex medical histories and polypharmacy.
• Observed birth defects were varied, including oral clefts, but statistical analyses (observed:expected ratios with 95% CIs including 1.0) did not indicate a significant risk for specific defects.

Conclusions:

• The observed pattern of birth defects among hydroxychloroquine-exposed infants did not suggest a specific teratogenic effect.
• Current findings provide no meaningful evidence for an increased risk of specific birth defects.
• Results should be interpreted with caution due to the small number of hydroxychloroquine-exposed cases.