Supernumerary nipples and renal anomalies in neonates.

A high rate of association between supernumerary nipples (SNNs) and hidden renal anomalies has previously been reported. We examined 2035 term infants and detected SNNs in 49. Only one patient, at age 4 months, was found to have a renal anomaly, as determined by ultrasound examination. The likelihood of finding a renal anomaly in a term infant with an SNN is likely to be lower than previously reported.