We thank Prof. Waldinger for his excellent discussion of lifelong premature ejaculation , but we are concerned that he makes no mention of the possible effects of circumcision on the human sexual response, including ejaculation. Although male circumcision may be uncommon in the Netherlands, male circumcision is widely practised in the Muslim nations, in Israel, in the USA, and to a lesser extent in other English-speaking nations, which results in ≈ 20% of the world's males being circumcised . We think some additional comment is in order.
Taylor et al. showed that circumcision typically removes more than half the skin and mucosa of the penis. They also reported the existence of a ridged band of highly innervated mucosal tissue just inside the tip of the prepuce near the mucocutaneous boundary . Winkelmann  called the mucocutaneous boundary a specific erogenous zone. The ridged band is invariably removed by circumcision; the removal of so much highly innervated tissue must affect the sensory input to both the CNS and the autonomic nervous system, and therefore is likely to affect human sexual response. Some would postulate that removing so much sensory tissue would be likely to delay ejaculation.
However, others take a different view. When a normal intact male has coitus the foreskin typically partially or totally engulfs the glans penis on the outstroke . Halata and Munger  report that the principal innervation of the glans penis is near the corona. Zwang  argues that circumcision denudes the penis and fully exposes the corona of the glans penis to direct stimulation, and that although nerves have been lost to circumcision, the direct stimulation of the corona hyperstimulates that area, thereby causing circumcised males to have a greater incidence of premature ejaculation. There is some evidence to support this hypothesis. O’Hara and O’Hara  carried out a survey of women's preferences for the circumcised or intact penis in their male partners. The women reported that their circumcised male partners were more likely to have premature ejaculation than were intact partners . In addition, a survey of males carried out in Queensland found that circumcised males were more likely to report premature ejaculation . Furthemore, circumcision may also degrade erectile function. Fink et al. reported degraded erectile function after circumcision of men. Immerman and Mackey  suggested that circumcision may cause brain re-organization caused by sensory deprivation. This too may affect male sexual response.
Male circumcision appears to be a confounding factor in studies of sexual response. We further suggest that studies in the USA might not give a fair picture because so many men in the USA are circumcised. The National Health and Social Life Survey reported a circumcision incidence of 77% amongst males born in the USA . This high incidence of circumcised males in the population may distort results obtained from USA-based studies of sexual function in one way or another. More study is needed. We propose that any future studies of sexual function and sexual problems should record the circumcision status of subjects and controls to see if any pattern emerges.