NEW THIS THURSDAY: SEVEN ITEMS ON MALE CIRCUMCISION AND SEXUAL FUNCTION

Tuesday, 27th of August 2013

SEVEN ITEMS ON MALE CIRCUMCISION AND SEXUAL FUNCTION

Dear All,

The benefits of male circumcision for preventing HIV acquisition in male heterosexuals are well established. Counter-arguments have been reviewed and rebutted in a recent review article, accessible at http://www.ghdonline.org/uploads/JLM2012_Male_circ_does_prevent_HIV_infection.pdf Promotion of voluntary male circumcision is now policy for UNAIDS and its sister organizations.

Many adolescents from non-circumcising cultures face the question of whether to have themselves circumcised. The following articles address the question, pertinent to them, of sexual function and satisfaction in the circumcised male and his female partner.

Good reading.

DOES MALE CIRCUMCISION AFFECT SEXUAL FUNCTION, SENSITIVITY, OR SATISFACTION? - A SYSTEMATIC REVIEW

J Sex Med. 2013 Aug 12. doi: 10.1111/jsm.12293. [Epub ahead of print]

Morris BJ, Krieger JN.

Source

School of Medical Sciences, University of Sydney, Sydney, New South Wales, Australia.

Abstract below; full text available to journal subscribers

INTRODUCTION:

Circumcision of males is commonly carried out worldwide for reasons of health, medical need, esthetics, tradition, or religion. Whether circumcision impairs or improves male sexual function or pleasure is controversial.

AIMS:

The study aims to conduct a systematic review of the scientific literature.

METHODS:

A systematic review of published articles retrieved using keyword searches of the PubMed, EMBASE, and Cochrane databases was performed.

MAIN OUTCOME MEASURES:

The main outcome measure is the assessment of findings in publications reporting original data relevant to the search terms and rating of quality of each study based on established criteria.

RESULTS:

Searches identified 2,675 publications describing the effects of male circumcision on aspects of male sexual function, sensitivity, sensation, or satisfaction. Of these, 36 met our inclusion criteria of containing original data. Those studies reported a total of 40,473 men, including 19,542 uncircumcised and 20,931 circumcised. Rated by the Scottish Intercollegiate Guidelines Network grading system, 2 were 1++ (high quality randomized controlled trials) and 34 were case-control or cohort studies (11 high quality: 2++; 10 well-conducted: 2+; 13 low quality: 2-). The 1++, 2++, and 2+ studies uniformly found that circumcision had no overall adverse effect on penile sensitivity, sexual arousal, sexual sensation, erectile function, premature ejaculation, ejaculatory latency, orgasm difficulties, sexual satisfaction, pleasure, or pain during penetration. Support for these conclusions was provided by a meta-analysis. Impairment in one or more parameters was reported in 10 of the 13 studies rated as 2-. These lower-quality studies contained flaws in study design (11), selection of cases and/or controls (5), statistical analysis (4), and/or data interpretation (6); five had multiple problems.

CONCLUSION:

The highest-quality studies suggest that medical male circumcision has no adverse effect on sexual function, sensitivity, sexual sensation, or satisfaction. Morris BJ and Krieger JN. Does male circumcision affect sexual function, sensitivity, or satisfaction?-A systematic review. J Sex Med **;**:**-**.

EFFECTS OF CIRCUMCISION ON MALE SEXUAL FUNCTIONS: A SYSTEMATIC REVIEW AND META-ANALYSIS

Asian J Androl. 2013 Jun 10. doi: 10.1038/aja.2013.47. [Epub ahead of print]

Tian Y, Liu W, Wang JZ, Wazir R, Yue X, Wang KJ.

Source

Department of Urology, West China Hospital, Sichuan University, Chengdu 610041, China.

Abstract below; full text available to journal subscribers

This meta-analysis was performed to assess sexual functions following adult male circumcision. We searched the Cochrane Central Register of Controlled Trials, PUBMED, EMBASE, the Cochrane Database of Systematic Review and Web of Science from their inception until January 2013 to identify all eligible studies that reported on mens sexual function after circumcision. The Cochrane Collaborations RevMan 5.2 software was employed for data analysis, and the fixed or the random effect model was selected depending on the proportion of heterogeneity. We identified 10 studies, which described a total of 9317 circumcised and 9423 uncircumcised men who were evaluated for the association of circumcision with male sexual function. There were no significant differences in sexual desire (odds ratio (OR): 0.99; 95% confidence interval (CI): 0.92-1.06), dyspareunia (OR: 1.12; 95% CI: 0.52-2.44), premature ejaculation (OR: 1.13; 95% CI: 0.83-1.54), ejaculation latency time (OR: 1.33; 95% CI: 0.69-1.97), erectile dysfunctions (OR: 0.90; 95% CI: 0.65-1.25) and orgasm difficulties (OR: 0.97; 95% CI: 0.83-1.13). These findings suggest that circumcision is unlikely to adversely affect male sexual functions. However, these results should be evaluated in light of the low quality of the existing evidence and the significant heterogeneity across the various studies. Well-designed and prospective studies are required for a further understanding of this topic.Asian Journal of Andrology advance online publication, 10 June 2013; doi:10.1038/aja.2013.47.

SENSATION AND SEXUAL AROUSAL IN CIRCUMCISED AND UNCIRCUMCISED MEN

J Sex Med. 2007 May;4(3):667-74. Epub 2007 Apr 6.

Payne K, Thaler L, Kukkonen T, Carrier S, Binik Y.

Source

Riverside Professional Center, Ottawa, Ontario, Canada. kimberley.payne@mail.mcgill.ca

Abstract below; full text is available to journal subscribers.

INTRODUCTION:

Research, theory, and popular belief all suggest that penile sensation is greater in the uncircumcised as compared with the circumcised man. However, research involving direct measurement of penile sensation has been undertaken only in sexually functional and dysfunctional groups, and as a correlate of sexual behavior. There are no reports of penile sensation in sexually aroused subjects, and it is not known how arousal affects sensation. In principle, this should be more closely related to actual sexual function.

AIM:

This study therefore compared genital and nongenital sensation as a function of sexual arousal in circumcised and uncircumcised men.

METHODS:

Twenty uncircumcised men and an equal number of age-matched circumcised participants underwent genital and nongenital sensory testing at baseline and in response to erotic and control stimulus films. Touch and pain thresholds were assessed on the penile shaft, the glans penis, and the volar surface of the forearm. Sexual arousal was assessed via thermal imaging of the penis.

RESULTS:

In response to the erotic stimulus, both groups evidenced a significant increase in penile temperature, which correlated highly with subjective reports of sexual arousal. Uncircumcised men had significantly lower penile temperature than circumcised men, and evidenced a larger increase in penile temperature with sexual arousal. No differences in genital sensitivity were found between the uncircumcised and circumcised groups. Uncircumcised men were less sensitive to touch on the forearm than circumcised men. A decrease in overall touch sensitivity was observed in both groups with exposure to the erotic film as compared with either baseline or control stimulus film conditions. No significant effect was found for pain sensitivity.

CONCLUSION:

These results do not support the hypothesized penile sensory differences associated with circumcision. However, group differences in penile temperature and sexual response were found.

THE EFFECT OF MALE CIRCUMCISION ON SEXUAL SATISFACTION AND FUNCTION, RESULTS FROM A RANDOMIZED TRIAL OF MALE CIRCUMCISION FOR HUMAN IMMUNODEFICIENCY VIRUS PREVENTION, RAKAI, UGANDA

BJU Int. 2008 Jan;101(1):65-70.

Kigozi G, Watya S, Polis CB, Buwembo D, Kiggundu V, Wawer MJ, Serwadda D, Nalugoda F, Kiwanuka N, Bacon MC, Ssempijja V, Makumbi F, Gray RH.

Source

Rakai Health Sciences Program, Entebbe, Uganda.

Abstract below; full text available to journal subscribers

OBJECTIVE:

To investigate the relationship between adult male circumcision and sexual satisfaction and function in men, as observational studies on the effect of adult male circumcision on sexual satisfaction show conflicting results.

SUBJECTS AND METHODS:

We investigated self-reported sexual satisfaction and function among men enrolled in a randomized trial of male circumcision for human immunodeficiency virus (HIV) prevention conducted in Rakai, Uganda. In all, 4456 sexually experienced HIV-negative males aged 15-49 years were enrolled; 2210 were randomized to receive immediate circumcision (intervention arm) and 2246 to circumcision delayed for 24 months (control arm). Men were followed up at 6, 12 and 24 months, and information on sexual desire, satisfaction and erectile dysfunction was collected. These variables were compared between the study arms and over time within the study arms, using chi-square or Fishers exact tests. The trial registration number is NCT00425984.

RESULTS:

There were no differences between the study arms at enrollment and problems with sexual satisfaction and function were reported by <2% of participants in both study arms at all time points. At 6 months, no difficulty with penetration was reported by 98.6% of circumcised men and 99.4% of controls (P = 0.02), and no pain on intercourse was reported by 99.4% circumcised and 98.8% of uncircumcised men (P = 0.05). There were no differences between the study arms in penetration or dyspareunia at later visits. Sexual satisfaction increased from 98.0% at enrollment to 99.9% at 2 years among the controls (P < 0.001), but there was no trend in satisfaction among circumcised men (enrollment 98.5%, 2 years 98.4%, P = 0.8).

CONCLUSION:

Adult male circumcision does not adversely affect sexual satisfaction or clinically significant function in men.

SEXUAL SATISFACTION OF WOMEN PARTNERS OF CIRCUMCISED MEN IN A RANDOMIZED TRIAL OF MALE CIRCUMCISION IN RAKAI, UGANDA

BJU Int. 2009 Dec;104(11):1698-701. doi: 10.1111/j.1464-410X.2009.08683.x. Epub 2009 Jun 12.

Kigozi G, Lukabwe I, Kagaayi J, Wawer MJ, Nantume B, Kigozi G, Nalugoda F, Kiwanuka N, Wabwire-Mangen F, Serwadda D, Ridzon R, Buwembo D, Nabukenya D, Watya S, Lutalo T, Nkale J, Gray RH.

Source

Rakai Health Sciences Program, Entebbe, Uganda. gkigozi@rhsp.org

Abstract

OBJECTIVE:

To investigate the effect of adult medical male circumcision on female sexual satisfaction.

SUBJECTS AND METHODS:

We investigated self-reported sexual satisfaction among 455 women partners of men circumcised in a randomized trial of male circumcision for the prevention of human immunodeficiency virus in Rakai, Uganda. Women aged 15-49 years were interviewed about their sexual satisfaction before and after their partners were circumcised. We analysed female-reported changes in sexual satisfaction using chi-square or Fishers exact tests.

RESULTS:

Only 2.9% (13/455) of women reported less sexual satisfaction after their partners were circumcised; 57.3% (255/455) reported no change in sexual satisfaction and 39.8% (177/455) reported an improvement in sexual satisfaction after their partners circumcision. There were no statistically significant differences in sexual satisfaction before and after partners circumcision by age, religion and education status.

CONCLUSION:

The overwhelming majority of women (97.1%) report either no change or improved sexual satisfaction after their male partner was circumcised. These findings suggest that male circumcision has no deleterious effect on female sexual satisfaction.

MALE CIRCUMCISION AND SEXUAL FUNCTION IN MEN AND WOMEN: A SURVEY-BASED, CROSS-SECTIONAL STUDY IN DENMARK†

Volume 40, Issue 5, Pp. 1367-1381.

International Journal of Epidemiologyije.oxfordjournals.org

Int. J. Epidemiol. (2011) 40 (5): 1367-1381. doi: 10.1093/ije/dyr104 First published online: June 14, 2011

Morten Frisch 1,*, Morten Lindholm 1 and Morten Grønbæk 2

+ Author Affiliations

1Department of Epidemiology Research, Statens Serum Institut, DK-2300 Copenhagen S, Denmark and 2National Institute of Public Health, DK-1353 Copenhagen K, Denmark

↵*Corresponding author. Department of Epidemiology Research, Statens Serum Institut, 5 Artillerivej, DK-2300 Copenhagen S, Denmark. E-mail: mfr@ssi.dk

Accepted May 26, 2011.

Abstract below; full text is at http://ije.oxfordjournals.org/content/40/5/1367.full

Background

One-third of the worlds men are circumcised, but little is known about possible sexual consequences of male circumcision. In Denmark (~5% circumcised), we examined associations of male circumcision with a range of sexual measures in both sexes.

Methods

Participants in a national health survey (n = 5552) provided information about their own (men) or their spouses (women) circumcision status and details about their sex lives. Logistic regression-derived odds ratios (ORs) measured associations of circumcision status with sexual experiences and current difficulties with sexual desire, sexual needs fulfilment and sexual functioning.

Results

Age at first intercourse, perceived importance of a good sex life and current sexual activity differed little between circumcised and uncircumcised men or between women with circumcised and uncircumcised spouses. However, circumcised men reported more partners and were more likely to report frequent orgasm difficulties after adjustment for potential confounding factors [11 vs 4%, ORadj = 3.26; 95% confidence interval (CI) 1.42–7.47], and women with circumcised spouses more often reported incomplete sexual needs fulfilment (38 vs 28%, ORadj = 2.09; 95% CI 1.05–4.16) and frequent sexual function difficulties overall (31 vs 22%, ORadj = 3.26; 95% CI 1.15–9.27), notably orgasm difficulties (19 vs 14%, ORadj = 2.66; 95% CI 1.07–6.66) and dyspareunia (12 vs 3%, ORadj = 8.45; 95% CI 3.01–23.74). Findings were stable in several robustness analyses, including one restricted to non-Jews and non-Moslems.

Conclusions

Circumcision was associated with frequent orgasm difficulties in Danish men and with a range of frequent sexual difficulties in women, notably orgasm difficulties, dyspareunia and a sense of incomplete sexual needs fulfilment. Thorough examination of these matters in areas where male circumcision is more common is warranted.

DOES SEXUAL FUNCTION SURVEY IN DENMARK OFFER ANY SUPPORT FOR MALE CIRCUMCISION HAVING AN ADVERSE EFFECT?

International Journal of Epidemiologyije.oxfordjournals.org

Int. J. Epidemiol. (2012) 41 (1): 310-326. doi: 10.1093/ije/dyr180 First published online: November 28, 2011

Brian J Morris 1,*, Jake H Waskett 2 and Ronald H Gray 3

+ Author Affiliations

1School of Medical Sciences, University of Sydney, Sydney NSW 2006, Australia, 2Circumcision Independent Reference and Commentary Service, 157 Stand Lane, Radcliffe, Manchester M26 1JR, UK and 3Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205, USA

↵*Corresponding author. School of Medical Sciences and Bosch Institute, Building F13, University of Sydney, Sydney NSW 2006, Australia. E-mail: brian.morris@sydney.edu.au

ARTICLE

In the current issue of International Journal of Epidemiology Frisch et al. extend previous research that showed 11% of sexually active Danish men and women fulfilled rather stringent criteria for having at least one sexual dysfunction.1 Their new survey examined associations with male circumcision (MC).2 Of 5395 men invited to participate, 48% accepted, and 1893 uncircumcised and 203 circumcised men were interviewed, as were 40% of the 5521 female partners invited. The survey involved 12 questions related to sexual activity and function. The findings for uncircumcised and circumcised participants were largely similar, there being no difference in age at first intercourse, perceived importance of a good sex life, sexual activity with partner in the past year, frequency of sex, sexual function overall, premature ejaculation, erectile difficulties or dyspareunia (painful intercourse).

The only differences found were (i) that circumcised men had a greater number of sex partners since age 15 and (ii) under orgasm difficulties (where the options were no, occasional or frequent), 10 of the 95 circumcised men reported frequent. The authors stated that most men, circumcised or otherwise, reported no or only occasional difficulties.

A note of caution is, however, needed in interpretation of these new findings. Before explaining our reservation, it may be worth noting that under Conflicts of interest Frisch declares his active involvement in opposition to MC. The tone of the paper accords with such a stance.

The low participation rates are concerning as these can lead to self-selection bias. The statistics merit particular scrutiny. The large number of predictors in their statistical model versus the relatively small number of circumcised men with frequent orgasm difficulties (10 circumcised) and women with dyspareunia (n = 8) is problematic, and may indicate overfitting and, consequently, instability in the model. The study also did not correct for multiple testing.

Another concern is that their use of odds ratios (ORs) as a measure of association is inappropriate if the outcome of interest is common (>10%). The prevalence risk ratio is the more appropriate measure.3,4 As an example, the authors report an odds ratio of 3.26 [95% confidence interval (95% CI) 1.15–9.27] for frequent sexual function difficulties in women with circumcised partners (31%) compared with uncircumcised partners (22%), whereas the prevalence risk ratio is 1.41. All of the odds ratios for frequent outcomes are similarly biased, and this exaggerates the apparent associations.

Without evidence, Frisch et al. argue for reduced penile sensitivity as being responsible for their findings. However, this explanation is questionable since medical MC in Denmark is only partial (CH Anderson, personal communication) and the foreskin is not removed as it is for MC in most other countries such as the USA. Thus, the men who self-reported that they were circumcised may still have had residual foreskin tissue and its associated nerve endings. The only exception would have been the 4% who were Muslim and 2% Jewish who had religious circumcisions. In all, 89% of the circumcised men were Lutheran or not religious, i.e. were typical of a traditional Danish population. Moreover, the fact that 85% had their circumcision after infancy is consistent with it having been performed for treatment of foreskin pathology such as phimosis (which affects ~10%—not 1%—of boys by their late teens5). Moreover, virtually all credible research,5 including clinical measurements and large randomized controlled trials (RCTs),6,7 that the authors disparage, show no difference in sensation or sensitivity during arousal as a result of MC. Their claim that reduced penile sensitivity [of the circumcised penis is] supported by recent neurophysiological studies uses as support a flawed study funded NOCIRC in which a subsequent proper statistical analysis of the data revealed no difference.8 One of the large RCTs, moreover, found that circumcised men reported increased penile sensitivity and enhanced ease of reaching orgasm.6

If their frequent orgasm difficulties finding were valid, a possible reason could be that the data emanate from a population in which very few men are circumcised (here 5%). Psychological factors can affect sexual function. In this regard, Frisch et al. admit that their study had limited statistical power to address whether the observed associations with sexual difficulties applied particularly to neonatal circumcisions or operations performed after infancy. A study in Sydney of men who have sex with men (MSM) noted some associations between MC and sexual difficulties only among those men who had been circumcised after infancy.9 Because of their foreskin problems and associated penile pain and/or difficulties, these men had already acquired behavioural aversions and sexual practices that meant they engaged in less penetrative sex than men who had never had penile problems. Since most of the Danish circumcised men were likely circumcised post-infancy for a medical reason, the majority of the circumcised men in the Frisch study would likely have been previously uncircumcised men who had had a lingering medical problem that one might suspect of causing them distress. If true, as is likely, the findings argue in favour of circumcision in infancy as a prophylactic measure to prevent later medical, and associated sexual and thus psychological, problems that then require medical intervention. Research in China has, moreover, found that men with redundant prepuce or phimosis have poor mental health.10 Psychological factors were also implicated in a Swedish study that reported slight shyness in the school changing-room in 9% of boys after circumcision for medical reasons.11 Could it be that, being aware that their penis looks different from that of most other Danish men, some may suffer anxiety during sex with a fellow countrywoman unused to a circumcised penis?

The findings for women are at odds with a survey in Mexico of women who had experienced sexual intercourse with the same partner before and 2 months after his circumcision.12 That study found no difference in general sexual satisfaction, pain during vaginal penetration, desire and vaginal orgasm.

The findings are also at odds with data from a large RCT of MC for HIV prevention in healthy men.13 Like the men, their wives had experienced intercourse both before and after the procedure, meaning they could compare what it was like with the same man over time. The women reported either no change (57%) or improved (40%) sexual satisfaction after their male partners had been circumcised. One reason was improved genital hygiene of their male partners. The authors of the RCT concluded that MC has no deleterious effect on female sexual satisfaction, and that it might, moreover, have social benefits in addition to the established health benefits.

Frisch et al. fail to point out that dyspareunia can be due to psychological causes. This is likely to be an important factor in the context of a society in which 95% of the men are uncircumcised. So could a type of penis that the women are unused to explain in part the report of dyspareunia by 8 of the 68 (11.8%) female participants when having sexual intercourse with circumcised men?

In contrast to statements to the contrary by Frisch et al. in their paper, rather than a widespread belief, there is now strong evidence from a large meta-analysis and RCTs, as well as biological support, that indeed circumcision provides superior penile hygiene and protects against urinary tract infections, phimosis, paraphimosis, balanoposthitis, venereal [sic] diseases and [genital] cancer.5 Their claim that reduced risks of balanoposthitis, sexually transmitted infections and penile cancer, can be achieved without tissue loss through the maintenance of good penile hygiene combined with proper use of condoms has limited or no research support. For example, phimosis, the biggest risk factor for penile cancer (OR = 12),14 is only eliminated by MC, hygiene does not reduce penile cancer risk15 and condoms offer only partial protection against oncogenic human papillomavirus,14 whereas RCT data show MC reduces HPV-related flat penile lesions by 98%.16 HIV transmission in industrialized parts of the world is mostly from receptive anal intercourse among MSM and contaminated needles, although for heterosexual men MC offers similar protection during intercourse with an infected woman in the USA as in sub-Saharan Africa.5 Moreover, in contrast to the selectively cited outlier studies, data from multiple large populations and a meta-analysis17 suggest female partners of circumcised men may be at lower risk of HIV.

The paper ends with a plea to the WHO to consider the possible sexual consequences of circumcision. The Danish study, however, provides no convincing evidence of sexual dysfunction in circumcised men given the potential self-selection bias due to low participation rates, the potential confounding by indication among the majority of men who were circumcised at older ages, and the inappropriate statistical analyses. We therefore consider that the WHO and other bodies such as the Centers for Disease Control and Prevention should have no qualms in supporting MC as a safe, effective procedure whose benefits far outweigh any immediate risks,5 and where considerable research has failed to provide convincing evidence for any adverse long-term effects on sexual function.

References

↵ Christensen BS, Grønbaek M, Osler M, et al

. Sexual dysfunctions and difficulties in Denmark: prevalence and associated sociodemographic factors. Arch Sex Behav 2011;40:121-32.

↵ Frisch M, Lindholm M, Grønbeck M

. Male circumcision and sexual function in men and women: a survey-based-cross-sectional study in Denmark. Int J Epidemiol 2011;40:1367-81.

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↵ Krieger JN, Mehta SD, Bailey RC, et al

. Adult male circumcision: effects on sexual function and sexual satisfaction in Kisumu, Kenya. J Sex Med 2008;5:2610-22.

↵ Kigozi G, Watya S, Polis CB, et al

. The effect of male circumcision on sexual satisfaction and function, results from a randomized trial of male circumcision for human immunodeficiency virus prevention, Rakai, Uganda. BJU Int 2008;101:65-70.

↵ Waskett JH, Morris BJ

. Fine-touch pressure thresholds in the adult penis. (Critique of Sorrells ML et al. BJU Int 2007;99:864-69.). BJU Int 2007;99:1551–52.

↵ Mao LM, Templeton DJ, Crawford J, et al

. Does circumcision make a difference to the sexual experience of gay men? Findings from the Health in Men (HIM) Cohort. J Sex Med 2008;5:2557-61

↵ Yang L, Ruan LM, Yan ZJ, et al

. [Sexual function and mental state in patients with redundant prepuce or phimosis]. (Article in Chinese.). Zhonghua Nan Ke Xue 2010;16:1095-97.

↵ Stenram A, Malmfors G, Okmian L

. Circumcision for phimosis: a follow-up study. Scand J Urol Nephrol 1986;20:89-92.

↵ Cortés-González JR, Arratia-Maqueo JA, Gómez-Guerra LS

. Does circumcision have an effect on females perception of sexual satisfaction? [in Spanish]. Rev Invest Clin 2008;60:227-30.

↵ Kigozi G, Lukabwe I, Kagaayi J, et al

. Sexual satisfaction of women partners of circumcised men in a randomized trial of male circumcision in Rakai, Uganda. BJU Int 2009;104:1698-701.

↵ Morris BJ, Gray RH, Castellsague X, et al

. The strong protection afforded by circumcision against cancer of the penis. (Invited Review). Adv Urol 2011. Article ID 812368:1–21.

↵ Tsen HF, Morgenstern H, Mack T, et al

. Risk factors for penile cancer: results of a population-based case-control study in Los Angeles County (United States). Cancer Causes Control 2001;12:267-77.

↵ Backes DM, Bleeker MC, Meijer CJ, et al

. Male circumcision is associated with a lower prevalence of human papillomavirus-associated penile lesions among Kenyan men. Int J Cancer 2011. [Epub 26 May 2011].

↵ Weiss HA, Hankins CA, Dickson K

. Male circumcision and risk of HIV infection in women: a systematic review and meta-analysis. Lancet Infect Dis 2009;9:669-77.

Letter to the Editor: Morten Frisch

Author Response to: Does sexual function survey in Denmark offer any support for male circumcision having an adverse effect? Int. J. Epidemiol. (2012) 41 (1): 312-314 first published online November 28, 2011 doi:10.1093/ije/dyr181