Many different “medical benefits” of circumcision have been claimed, but the only one in which a “statistically significant” benefit has been shown consistently is that circumcised infants are less prone to urinary tract infection (UTI) in the first year of life. After that time, the risk of UTI in both circumcised and normal (intact) males drops to a rate far below that of females throughout the rest of life.

A recent study, initially involving over 58,434 boys in Ontario, was published in the Lancet (1). The relative risk of hospital admission for UTI in the first year of life was 3.7, meaning an intact boy was 3.7 times more likely to be hospitalised for a UTI than his circumcised counterpart. This was highly statistically significant and sounds meaningful until you consider the absolute rarity of UTI’s. The absolute risk of a UTI was 1.88 per 1000 person-years in circumcised boys and 7.02 per 1000 in normal boys. In other words, a normal intact boy has a 99.298% chance of getting through his first year of life without a UTI, whereas a circumcised boy increases his chances to 99.812% (see graph below). Another way of stating this is that 195 circumcisions would be needed to prevent one UTI hospitalization (as shown in graphic above).

In addition, a realistic rate of short-term complications of circumcision is 2 to 10 percent (2). Therefore, somewhere between 4 to 20 complications could be expected for every UTI prevented by surgery (shown in graphic at top of page). Other complications may not show up until sexual maturity, and their true incidence is unknown. It is also known that many infants who get urinary tract infections have underlying congenital anomalies of the urinary tract.

Other interventions are known to significantly decrease the rate of UTI’s, including breastfeeding (because of protective maternal antibodies) and early rooming-in at the hospital after delivery (to colonize the baby with the mother’s harmless skin bacteria instead of more virulent hospital nursery bacteria). In addition, UTI’s are easily treated with antibiotics.

Most studies of UTI’s in infants have serious shortcomings, because the way the UTI is determined is problematic. Urine from the diaper or an external plastic bag is more likely to be contaminated by skin bacteria in intact boys. The only sure method of diagnosis is a suprapubic needle aspiration of the bladder, which was not done systematically in any known study of circumcision and UTI. In addition, in parts of North America where the infant circumcision rate is very high, virtually the only infants to leave the hospital after birth without having been circumcised are premature or sick infants, who may also have a greater tendency to develop urinary tract infections.

The March 1999 AAP statement notes:

Few of the studies that have evaluated the association between UTI in male infants and circumcision status have looked at potential confounders (such as prematurity, breastfeeding, and method of urine collection) in a rigorous way. For example, because premature infants appear to be at increased risk for UTI, the inclusion of hospitalized premature infants in a study population may act as a confounder by suggesting an increased risk of UTI in uncircumcised infants. Premature infants usually are not circumcised because of their fragile health status.

In another example, breastfeeding was shown to have a threefold protective effect on the incidence of UTI in a sample of uncircumcised infants (3). However, breastfeeding status has not been evaluated systematically in studies assessing UTI and circumcision status.

Note that the protective effect of breastfeeding is roughly equivalent to that of circumcision but poses no risk.

No discussion of amputating a normal body part to prevent a potential medical condition would be complete without consideration of the loss of function entailed by the amputation (4). The foreskin is highly erogenous tissue, densely packed with unique nerve endings. It provides a sensory role during sexual activity, as well as a mechanical lubricating role, and a protective role throughout life. The tissue removed from the infant would grow to roughly the size of a 3 by 5 inch index card as he becomes an adult.

Conclusion: It is misleading to speak of a medical “benefit” of a procedure when serious complications occur at a rate far greater than the problem the procedure was meant to address, when less invasive but effective interventions are available, and when the procedure results in a permanent loss of function. Any medical professional who seriously believes that circumcision is a worthwhile measure to prevent urinary tract infection is either ignorant of the data, in denial, or too economically dependant on the continued income provided by circumcision to be objective. Any medical professional who understands the scientific evidence but who agrees to circumcise because of the parents’ misunderstanding of this issue is acting unethically, since a physician’s primary duty is to act in the best interest of his patient (the baby in this case, not the parents). The physician’s duty is to inform the parents of the relevant facts and correct their misconceptions when their beliefs are based on an erroneous understanding of the scientific literature regarding urinary tract infection and circumcision.

David Alwin, MD     

References

1. To T, Agha M, Dick PT, Feldman W. Cohort study on circumcision of newborn boys and subsequent risk of urinary-tract infection. Lancet 1998; 352: 1813-16.
2. Williams N, Kapila L. Complications of Circumcision. Br J Surg 1993; 80:1231-36.
3. Pisacane A, Graziano L, Mazzarella G, et al. Breast-feeding and urinary tract infection. J Pediatr 1992;120:87-89.
4. Taylor JR, Lockwood AP, Taylor AJ. The prepuce: Specialized mucosa of the penis and its loss to circumcision. Br J Urol 1996; 77:291-295.

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• A reasonable strategy for prevention of UTI. Excerpt from the Canadian Pediatric Society statement on circumcision.