Till 2005 it was not considered medically necessary. But in recent times, the practice of newborn circumcision is going up. 60 to 75% of males are circumcised in the United States. The percentage varies depending upon the ethnic groups and religion.

The main reason for this change is that several large studies showed that a 60% decrease in HIV transmission in circumcised males compared to uncircumcised males. This has influence in the decision of parents for newborn circumcision.

The circumcised penis is easier to keep clean. An uncircumcised boy must be taught properly how to clean his penis gently but thoroughly. This must happen mostly when the boys are three years old. Before that the retraction may not be possible and this is normal. Uncircumcised boys get more urinary tract infections. This is significant in infants. The reason is that circumcision prevents the growth of bacteria under the foreskin.

Uncircumcised men have higher risk of sexually transmitted diseases like syphilis, herpes simplex type-2 and human papillomavirus. It is the case with HIV infection also. Gonorrhoea and inflammation of the urethra are less common in circumcised men.

Less infection with human papilomavirus means the partner is also partially safe from cervical cancer. Penis cancer comes exclusively to uncircumcised men.

Circumcision increases the risk of the inflammation of the opening of the penis.