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Join Date: Jul 2000
Location: USA
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There are a few postulated reasons for the function of the mammalian foreskin. The nerve concentration and moisture of the foreskin has lead to speculation that it improves sexual performance and satisfaction, but the evidence from objective clinical studies such as The National Health and Social Life Survey doesn’t support that conjecture; Laumann et. al. in Circumcision in the United States. Prevalence, prophylactic effects, and sexual practice. J Am Med Assoc 1997; 277: 1052-7 found that circumcision is actually associated with a decreased risk of sexual dysfunction. There are very few other objective peer-reviewed clinical studies looking at the effects of circumcision upon sexual function or satisfaction, and the inclusion of men who underwent the procedure for medical or religious reasons may bias the results.
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J Urol. 2002 May;167(5):2111-2. Effects of circumcision on male sexual function: debunking a myth? Collins S, Upshaw J, Rutchik S, Ohannessian C, Ortenberg J, Albertsen P.
Department of Urology, Louisiana State University School of Medicine, New Orleans, Louisiana, USA.
PURPOSE: Claims of superior sexual sensitivity and satisfaction for uncircumcised males have never been substantiated in a prospective fashion in the medical literature. We performed such a study to investigate these assertions. MATERIALS AND METHODS: The Brief Male Sexual Function Inventory (BMSFI) was administered to sexually active males older than 18 years before undergoing circumcision. After a minimum interval of 12 weeks after the operation, the survey was again administered. The 5 domains of the BMSFI (sexual drive, erections, ejaculation, problem assessment overall satisfaction) were each given a summed composite score. These scores before and after circumcision were then analyzed by Wilcoxon signed-rank testing. RESULTS: All 15 men who participated in the study between September 1999 and October 2000 were available for followup. Mean patient age plus or minus standard deviation was 36.9 +/- 12.0 years. There was no statistically significant difference in the BMFSI composite scores of reported sexual drive (p >0.68), erection (p >0.96), ejaculation (p >0.48), problem assessment (p >0.53) or overall satisfaction (p >0.72). CONCLUSIONS: Circumcision does not appear to have adverse, clinically important effects on male sexual function in sexually active adults who undergo the procedure.
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Most of these men had medical indications for circumcision which could skew the results in favor of the procedure. After all, if one’s foreskin has been painfully inflamed and irritated, it’s removal will likely be an improvement. That bias, along with the small sample size and relatively short follow-up may have confounded the study.
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Urology. 2004 Jan;63(1):155-8 Circumcision in adults: effect on sexual function. enkul T, IserI C, sen B, KarademIr K, Saracoglu F, Erden D. Department of Urology, GATA Haydarpasa Training Hospital, Uskudar, Istanbul, Turkey.
OBJECTIVES: To evaluate the effects of adult circumcision on sexual function in men circumcised only for religious or cosmetic reasons. METHODS: The study group consisted of 42 male patients with a median age of 22.3 years (range 19 to 28) referred for circumcision from June 2002 to January 2003. Of the 42 men, 39 desired circumcision for religious reasons. Before circumcision, their sexual performance was evaluated using the Brief Male Sexual Function Inventory (BMSFI) and ejaculatory latency time. The BMSFI evaluation and ejaculatory latency time measurements were repeated after a postoperative interval of at least 12 weeks. The scores in the five main sections of the BMSFI and the ejaculatory latency times before and after circumcision were analyzed. RESULTS: The differences in the mean BMSFI scores were not statistically significant in any of the five sections. However, the mean ejaculatory latency time was significantly longer after circumcision (P = 0.02). CONCLUSIONS: Adult circumcision does not adversely affect sexual function. The increase in the ejaculatory latency time can be considered an advantage rather than a complication.
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This study was small, had a short follow-up period, and was likely biased by the religious motivation for circumcision. Nonetheless, the increased ejaculatory latency time (ie. coitus time was about 1 minute longer following circumcision) didn’t result in decreased satisfaction. In other words, taking longer to ejaculate didn’t seem to bother these men.
Earlier this year a 65 year-old gentleman I saw put on his pre-operative history form that he had been circumcised a few years ago (I have never performed a circumcision, so the subject doesn't come up very often in my practice). Surprisingly, the circumcision didn’t have anything to do with his beliefs or medical condition; it was all because of his wife. She had been plagued by chronic vaginal yeast infections, and despite repeated courses of anti-fungals, the infection just wouldn’t completely clear. Though he was asymptomatic, his wife’s gynecologist suggested that he get circumcised after several dual his-and-her anti-fungal courses failed to resolve her. He did, and she never had another yeast infection. This previously intact man had no illness or religious belief that led him to get circumcised, so he was in a unique position to compare his pre and post circumcised state. What did he think of the results? “I just wish I had it done before,� he said; he felt that their sex life was better now than pre-circumcision, though he acknowledged that his wife could be enjoying sex more because the candida infection was gone. What about sensitivity and pleasure? The pleasure was just as good as before, and he felt that longer coitus was actually a benefit, not a detraction. Of course, all of this is highly subjective, and there are potentially billions of other anecdotes in the world today; we’ve seen just a small sample of them on these fora. There was a published study that found a majority of its female respondents preferred an intact penis, but this study was probably biased because it recruited subjects through an anti-circumcision newsletter. Had they recruited from a different population, say an Israeli newspaper, the results probably would have been much different although still biased.
Another possible reason for the foreskin may have to do with sexual attraction and territoriality. The vestibule created by the foreskin and glans can harbor cellular debris and small amounts of urine, seminal discharges, and other excretions. In the micro-environment they create, these compounds can caseate to create smegma, which contributes to a unique odor called musk Musk, in turn, may let others know of a male’s presence. This could be the case in other mammals, and it may even be attractive to some female mammals, but it’s not likely to be important in humans. Human evolution has resulted in the loss of many of the olfactory and pheremone receptors that other animals have, and there isn’t any good evidence to indicate that musky men attract more mates or repel potential competitors any better than others.
One function of the foreskin, at least from a microbial standpoint, is to provide an enhanced portal of entry. The microbial environment under the foreskin induces immunological changes that increase the concentration of high affinity receptors found on certain types of cells. These receptors in turn are what many infectious agents use to gain access to a human host. An example is HIV, which infects humans through specific receptors that are more numerous in uncircumcised penile heads, which may explain the increased risk of HIV acquisition associated with an intact foreskin:
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American Journal of Pathology 2002 Sep;161(3):867-73 Susceptibility to human immunodeficiency virus-1 infection of human foreskin and cervical tissue grown in explant culture. Patterson BK, et. al. Department of Pediatrics, Division of Infectious Diseases, Children's Memorial Hospital, Chicago.
Numerous studies have indicated a protective effect of male circumcision against acquisition of human immunodeficiency virus (HIV)-1. We investigated mechanisms responsible for the possible increased HIV-1 susceptibility of human foreskin. Foreskins from eight pediatric and six adult patients with (n = 3) and without (n = 11) histories of sexually transmitted disease were evaluated. Six cervical biopsies from HIV-1-seronegative women were included as controls. CD4(+) T cells, macrophages, and Langerhans' cells (LCs) were quantified using image analysis. Cells expressing HIV-1 co-receptors CCR5 and CXCR4 were quantified using immunofluorescence and image analysis. Foreskin biopsies were infected ex vivo in organotypic culture with HIV-1. HIV-1 DNA copies in foreskin and cervical mucosal tissue were compared and the infected cell phenotype was determined. Foreskin mucosa contained higher mean proportions of CD4(+) T cells (22.4%), macrophages (2.4%), and LCs (11.5%) in adults than in children (4.9%, 0.3%, and 6.2%, respectively) or in cervical mucosa (6.2%, 1.4%, and 1.5%, respectively). The highest proportions of CD4(+) T cells and LCs occurred in patients with a history of infection. Foreskin immune cells expressed predominantly the CCR5 HIV-1 co-receptor. Adult foreskin mucosa had greater susceptibility to infection with HIV(bal) than cervical mucosa or the external surface of foreskin tissue. Circumcision likely reduces risk of HIV-1 acquisition in men by decreasing HIV-1 target cells.
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These changes also occur in the glans of an uncircumcised penis; as a result, adult circumcision is not as likely to reduce the risk of HIV infection as well as neonatal circumcision does. A similar mechanism exists for HPV, which causes genital warts and is a risk factor for cervical cancer in women, which is why partners of intact men have been found to have a substantially higher risk for this malignancy compared with the partners of circumcised men. A similar combination of factors may also explain the increased risk of penile malignancies associated with an intact foreskin.
The Laumann study did not find evidence that circumcision reduces the risk of HIV, but it was conducted on an American population with a high rate of asexual and homosexual HIV transmission. Unlike the much of the world, HIV in the US is transmitted primarily through intravenous drug abuse and male homosexual sex, and circumcision is unlikely to offer much protection against either dirty needles or high risk anal-receptive sex. Several studies since then conducted on populations in which HIV is primarily transmitted by heterosexual sex have found circumcision to confer a markedly decreased risk of HIV infection, and several other studies have found a smaller but still significant risk reduction in HPV. These findings maintain statistical significance even when one corrects for other potentially confounding variables such as numbers of sex partners and cultural differences. Many studies since 1997 have been conducted to determine whether or not there is a protective effect against infectious diseases from circumcision, and there’s now overwhelming clinical evidence that circumcision confers a substantial reduction in the risk of HIV acquisition.
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Reprod Fertil Dev. 2004;16(5):555-9. The HIV/AIDS pandemic: new ways of preventing infection in men. Short RV. Department of Obstetrics and Gynaecology, University of Melbourne, Victoria 3010, Australia.
Nelson Mandela has recently said that HIV/AIDS is the greatest health crisis in human history. At the end of 2001, UNAIDS estimated that there were 40 million people living with the infection, with 5 million new cases, and 3 million deaths per year. About half the infected individuals are men, and heterosexual intercourse is the commonest route of infection. Although condoms remain the first line of defence, they are unpopular in parts of Africa, where the pandemic is worst, so an alternative is needed. Post-coital penile hygiene has received little attention. Wiping the glans penis and inner foreskin immediately after intercourse with an acidic solution like lemon or lime juice, or even vinegar, should immediately kill the virus and might prevent infection; clinical trials are urgently needed. Several studies in Africa and India have now conclusively demonstrated a 2-7-fold protective effect of male circumcision against HIV infection. Circumcision removes the inner foreskin and the frenulum, which are the prime sites of HIV entry into the penis...
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Lancet. 2004 Mar 27;363(9414):1039-40. Male circumcision and risk of HIV-1 and other sexually transmitted infections in India. Reynolds SJ, Shepherd ME, Risbud AR, Gangakhedkar RR, Brookmeyer RS, Divekar AD, Mehendale SM, Bollinger RC.
Division of Infectious Diseases, Johns Hopkins University Medical School, Ross 1150, 720 Rutland Avenue, Baltimore, Maryland 21205, USA.
Circumcised men have a lower risk of HIV-1 infection than uncircumcised men. Laboratory findings suggest that the foreskin is enriched with HIV-1 target cells. However, some data suggest that circumcision could simply be a marker for low-risk behaviours. In a prospective study of 2298 HIV-uninfected men attending sexually transmitted infection clinics in India, we noted that circumcision was strongly protective against HIV-1 infection (adjusted relative risk 0.15; 95% CI 0.04-0.62; p=0.0089); however, we noted no protective effect against herpes simplex virus type 2, syphilis, or gonorrhoea. The specificity of this relation suggests a biological rather than behavioural explanation for the protective effect of male circumcision against HIV-1.
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It may at first seem confusing or even suspicious that studies can now find evidence that wasn’t previously apparent, but it’s really not all that unusual in clinical studies. For instance; evidence of condom effectiveness for HIV prevention is based primarily on high-risk non-American populations as studies in the US did not consistently find a protective effect from condom use on HIV infection rates. To date, there have been no head-to-head  studies directly comparing and contrasting the efficacy of condoms to circumcision in the US or elsewhere, and there are no studies that show either one is more effective than the other. Neither condoms nor circumcision are 100% effective against HIV, and since each works differently, there’s no reason to believe that one negates the other. Condoms offer some protection against HIV, circumcision offers some, and since they work by different mechanisms, it’s likely that the two together provide more protection than either one alone. None of this means that circumcision or condoms cannot offer some protection for IV drug abusers or male homosexuals against HIV, but the protective effect of either is not absolute and may be overshadowed by high-risk behaviors such as needle-sharing and/or anal intercourse
Circumcison decreases the risk of neonatal urinary tract infections, which unlike most adult urinary tract infections are very serious and can lead to death or end-stage renal disease requiring long-term dialysis even when treated with antibiotics. However, even though the risk reduction is relatively high (greater than 3-fold), the overall benefit is low because neonatal UTIs are uncommon.
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Pediatrics. 2000 Apr;105(4 Pt 1):789-93Newborn circumcision decreases incidence and costs of urinary tract infections during the first year of life.Schoen EJ, Colby CJ, Ray GT.
Departments of Genetics and Pediatrics, Kaiser Permanente Medical Care Program of Northern California, Oakland, CA 94611, USA.
OBJECTIVE: To assess the effect of newborn circumcision on the incidence and medical costs of urinary tract infection (UTI) during the first year of life for patients in a large health maintenance organization. SETTING: Kaiser Permanente Medical Care Program of Northern California (KPNC). PATIENTS: The population consisted of members of KPNC. The study group consisted of a cohort of 28 812 infants delivered during 1996 at KPNC hospitals; of the 14 893 male infants in the group, 9668 (64.9%) were circumcised. A second cohort of 20 587 infants born in 1997 and monitored for 12 months was analyzed to determine incidence rates. DESIGN: Retrospective study of all infants consecutively delivered at 12 facilities. OUTCOME MEASURES: Diagnosis of UTI was determined from the KPNC computerized database using the International Classification of Diseases, Ninth Revision code for inpatients and KPNC Outpatient Summary Clinical Record codes for outpatients. A sample of 52 patient charts was reviewed to confirm the International Classification of Diseases, Ninth Revision and KPNC Outpatient Summary Clinical Record codes and provide additional data. RESULTS: Infants <1 year old who were born in 1996 had 446 UTIs (292 in females; 154 in males); 132 (86%) of the UTIs in males occurred in uncircumcised boys. The mean total cost of managing UTI was 2 times as high in males ($1111) as in females ($542). This higher total cost reflected the higher rate of hospital admission in uncircumcised males with UTIs (27.3%) compared with females (7.5%); mean age at hospitalization for UTI was 2.5 months old for uncircumcised boys and 6.5 months old for girls. In 1996, total cost of managing UTI in uncircumcised males ($155 628) was 10 times higher than for circumcised males ($15 466) despite the fact that uncircumcised males made up only 35.1% of the male patient base in 1996, reflecting the more frequent occurrence of UTI in uncircumcised males (132 episodes) than in circumcised males (22 episodes), and the larger number of hospital admissions in uncircumcised males (38) than in circumcised males (4). The incidence of UTI in the first year of life was 1:47 (2.15%) in uncircumcised males, 1:455 (.22%) in circumcised males, and 1:49 (2. 05%) in females. The odds ratio of UTI in uncircumcised:circumcised males was 9.1:1. CONCLUSIONS: Newborn circumcision results in a 9. 1-fold decrease in incidence of UTI during the first year of life as well as markedly lower UTI-related medical costs and rate of hospital admissions. Newborn circumcision during the first year of life is, thus, a valuable preventive health measure, particularly in the first 3 months of life, when uncircumcised males are most likely to be hospitalized with severe UTI.
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Lancet.1998 Dec 5;352(9143):1813-6. Cohort study on circumcision of newborn boys and subsequent risk of urinary-tract infection. To T, Agha M, Dick PT, Feldman W. Population Health Sciences, Research Institute, Hospital for Sick Children, Department of Public Health Sciences, University of Toronto, Ontario, Canada.
BACKGROUND: A decrease in risk of urinary-tract infection is one of the most commonly given reasons for circumcision of newborn boys. Previous studies have reported rates of UTI to be 10-20 times higher in uncircumcised than in circumcised boys. This population-based cohort study followed neonates in Ontario, Canada, prospectively to study the relation between circumcision and subsequent UTI risk. METHODS: Eligible boys were born to residents of Ontario between April 1, 1993, and March 31, 1994. We used hospital discharge data to follow up boys until March 31, 1996. FINDINGS: Of 69,100 eligible boys, 30,105 (43.6%) were circumcised and 38,995 (56.4%) uncircumcised. 888 boys circumcised after the first month of life were excluded. 29,217 uncircumcised boys were matched to the remaining circumcised boys by date of birth. The 1-year probabilities of hospital admission for UTI were 1.88 per 1000 person-years of observation (83 cases up to end of follow-up) in the circumcised cohort and 7.02 per 1000 person-years (247 cases up to end of follow-up) in the uncircumcised cohort (p<0.0001). The estimated relative risk of admission for UTI by first-year follow-up indicated a significantly higher risk for uncircumcised boys than for circumcised boys (3.7 [2.8-4.9]). 195 circumcisions would be needed to prevent one hospital admission for UTI in the first year of life. INTERPRETATION: Although our findings support the notion that circumcision may protect boys from UTI, the magnitude of this effect may be less than previously estimated.
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Finally, circumcision clearly confers a protective effect against penile carcinoma, a malignancy which may require amputation of the penis for cure:
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Lancet Oncol[/b]. 2004 Apr;5(4):240-7.Penile carcinoma: a challenge for the developing world.Misra S, Chaturvedi A, Misra NC.
Department of Surgical Oncology, King George's Medical College, Lucknow, India.
Although rare in developed countries, carcinoma of the penis is an important problem in the developing world. Circumcision done in childhood offers the greatest protection against this disease. Poor penile hygiene and phimosis are strong risk factors for development of penile carcinoma. Early disease can be treated by conventional resection of the penis, or in selected patients by organ preserving techniques including Mohs micrographic surgery, and laser and radiation therapy. For more advanced primary disease, partial or total penectomy is needed. Elective or therapeutic lymph-node dissection is recommended for inguinal metastatic disease, and depending on the disease status, unilateral or bilateral inguinal or ilioinguinal lymphadenectomy might be needed. The role of chemotherapy, as adjuvant or primary treatment in metastatic disease, needs to be defined in prospective clinical trials, which can be done in developing countries.
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Circumcision is not without risks, but complications resulting in life-threatening injury or permanent deformity are very rare. Nonetheless, the risks may not outweigh the benefits in some populations, particularly in developed countries, though the benefits may be more substantial in selected populations such as those with a high prevalence of HIV infection. Currently, those medical societies in the western world that have issued recommendations regarding routine neonatal circumcision have either been neutral, that is neither recommending for or against the procedure (ie. the American Academy of Pediatrics), or they have recommended against routine neonatal circumcision (ie. The Canadian Paediatric Society) Whether these recommendations will be altered as a result of more recent clinical findings remains to be seen, as does whether or not these recommendations should be applied to populations outside of the industrialized world.
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12-05-2004, 01:15 PM
