Nelson CP et al. (2005) The increasing incidence of congenital penile anomalies in the United States. J Urol 174: 1573–1576

A study of 4,837,224 males born between 1988 and 2000 has confirmed that the incidence of congenital penile anomalies in the US is rising. Furthermore, the study showed that white race, high socioeconomic status, private insurance and northeast geographic location significantly increased the odds of these anomalies.

Nelson and colleagues analyzed data from the Nationwide Inpatient Sample database, and found that the incidence of congenital penile anomalies increased significantly from 7.0/1,000 to 8.3/1,000 over the course of the study—a 12% increase.

Penile anomalies were seen almost twice as often in white newborns compared to those of Hispanic race. Multivariate analysis revealed that the odds of identifying anomalies were 19% higher in the highest socioeconomic category compared to the lowest category. The incidence also varied dramatically with geographic region, with the highest incidence seen in the northeast US and the lowest in the west.

The most common anomaly identified was HYPOSPADIAS, with the same demographic factors associated with a higher incidence.

The authors discuss the potential limitations of their study, including ascertainment bias, coding irregularities, and administrative data sources. Although the increasing incidence of congenital penile anomalies demonstrated in this study has been previously observed, there is little known regarding the underlying causes. Genetic, hormonal and environmental factors have been proposed, and the authors hope that their findings will encourage further research into possible etiologies.