Maternal febrile illnesses, medication use, and the risk of congenital renal anomalies

BACKGROUND Renal anomalies occur in about three infants per 1000 live births and have been associated with several environmental risk factors. Researchers have yet to assess the effect of maternal febrile illnesses on renal anomalies, even though febrile illnesses have been associated with other birth defects. Our objective was to determine whether maternal illness, fever, or medication use during the first trimester of pregnancy is associated with the occurrence of renal anomalies. METHODS In this population‐based case‐control study, we evaluated 192 infants with renal anomalies (renal agenesis [n = 44], obstructive defects [n = 134], and renal duplication defects [n = 14]) and 3029 infant without birth defects, all of whom were born in metropolitan Atlanta, Georgia, from 1968 through 1980. Maternal illness was defined as reported flu‐like illness and/or episodic illness during the first trimester. RESULTS Our adjusted multivariate analyses showed that among the 192 case‐infants, 38 had mothers with an illness (adjusted odds ratio [AOR], 1.71; 95% confidence interval [CI], 1.15–2.52), 20 had mothers who reported a fever (AOR, 1.80; 95% CI, 1.07–3.02) and 26 had mothers who reported taking medication (AOR, 1.69; 95% CI, 1.07–2.68). Fifteen mothers reported a fever and medication use (AOR, 1.90; 95% CI, 1.05–3.45). Nonprescription aspirin‐containing medication use showed the strongest association (AOR, 3.45; 95% CI, 1.36–8.75) with renal anomalies. CONCLUSIONS Our data suggest that maternal exposure to illness, fever, and medication (particularly aspirin) may increase the risk of congenital renal anomalies. Birth Defects Research (Part A), 2003. © 2003 Wiley‐Liss, Inc.