advanced search

<< Back To Home

NEW THIS THURSDAY: TWO FROM DENMARK ON MALE CIRCUMCISION AND SEXUAL FUNCTION

Tuesday, 27th of August 2013

• TWO ITEMS FROM DENMARK
• 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 Frisch1,*, Morten Lindholm1 and Morten Grønbæk2

+ 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 Morris1,*, Jake H Waskett2 and Ronald H Gray3

+ 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.

Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2011; all rights reserved.

 

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.

Abstract/FREE Full Text

↵ Barros AJ, Hirakata VN

. Alternatives for logistic regression in cross-sectional studies: an empirical comparison of models that directly estimate the prevalence ratio. BMC Med Res Methodol 2003;3:21.

↵ Savu A, Liu Q, Yasui Y

. Estimation of relative risk and prevalence ratio. Stat Med 2010;29:2269-81.

↵ Morris BJ

. Why circumcision is a biomedical imperative for the 21st century. BioEssays 2007;29:1147-58.

↵ 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