Medical research done over the past decades has provided conclusive evidence that male circumcision has many medical benefits. In fact, both the American Academy of Pediatricians (AAP) and the Centers for Disease Control (CDC) have endorsed male circumcision for health reasons: in December 2014 the US Centers for Disease Control (CDC) in Atlanta made a policy statement strongly supporting circumcision . The new draft guidelines mirror an updated policy on circumcision released by the American Academy of Pediatrics in 2012. For further information regarding the CDC Statement, see e.g. the article on Scientific American, and for more on the AAP Statement, see WebMD and CNN.

Medical studies have shown that circumcision greatly reduces the risk of urinary tract infections (UTI), especially in the first year of life. These infections can cause serious problems, especially in infants. For example, UTI can cause scarring of the kidney and ultimately hypertension or kidney failure. To make matters worse, studies have shown that UTI are becoming more resistant to anti-biotics, thereby making treatment both much harder and less effective.

Cancer of the penis is virtually non-existent in circumcised men. Of the 60000 cases reported since the 1930´s, fewer than 10 occurred in circumcised men. The risk of penile cancer in uncircumcised men is 1 case per 400-600 men, while in circumcised men it is 1 case per 75000 to 8 million men. Circumcision also helps to reduce the risk of cervical cancer in female partners. Prostate cancer may also be increased for uncircumcised men.

Extensive research done during the past 15 years have convincingly shown that infant circumcision reduces the risk of contracting sexually transmitted diseases, including HIV/AIDS (for further information, see the section on HIV/AIDS). Scientific studies done over the past 10 years or so have established that circumcision reduces female-to-male HIV transmission rates by around 60%. The medical evidence is now overwhelming. The main question has been how circumcision can best be introduced as a public health policy. International agencies like the United Nations have started voluntary male medical circumcision (VMMC) campaigns in e.g. many sub-Saharan countries to save the lives of men and women in regions particularly vulnerable to the spread of HIV. As a result many sub-Saharan countries have undertaken measures to dramatically increase circumcision. These measures have been ongoing for the past few years and have shown many positive effects already. These ongoing efforts to spread circumcision in developing nations in order to curb the spread of HIV are a triumph of common sense, global health initiatives, science, and basic humanity. For further information on VMMC see here.

Circumcision also eliminates problems like phimosis (non-retractable foreskin) and balanitis (inflammation of the foreskin). Even though these problems only occur in about 10% of men, they can be very painful if not treated. In older males, phimosis can cause urine blockage with acute hypersensitive kidney damage. Other painful problems that might occur include paraphimosis (where the retracted foreskin cannot be brought back again over the glans) and posthitis (inflammation of the foreskin). Uncircumcised men are often unaware that these problems are all related to the presence of a foreskin, and that the discomfort and pain that they are experiencing are easily treatable. In almost all cases, the only permanent treatment is circumcision.

A summary of a risk-benefit analysis of circumcision can be found in the flyer circ-risk-benefits