Supernumerary nipples and renal anomalies.

The authors found a total of 504 supernumerary nipples in healthy newborn infants, schoolchildren and patients in the paediatric ward and outpatient clinic. The prevalence of supernumerary nipples was 4.29% among newborn infants and 5.86% among schoolchildren; 496 children with supernumerary nipples were examined with ultrasound for renal malformations and 410 acutely ill patients served as controls. The other control group consisted of 1957 newborn infants routinely screened by ultrasound. The prevalence of renal anomalies was 3.74% in children with supernumerary nipples, 3.17% in the control group, 2.86% in newborn infants with supernumerary nipples and 1.89% in control newborn infants. The differences are not significant.