News item for July 11, 2017
Circumcision may actually IMPROVE sexual function!
Students of the medical sciences should be familiar with the hierarchy of evidence (*)
At the top of the pile we have randomised controlled trials (RCTs), systematic reviews and meta-analyses. The studies intactivists cherry pick all come from lower down the hierarchy. Like the studies conducted in Belgium and Denmark by Bronselaer (2013) and Frisch (2011) respectively, which were cross-sectional in design (despite the word “cohort” in the title of the former), and are endlessly cited by opponents of circumcision. And much of what intactivists say is right at the bottom – opinions.
Until now, on the topic of the effect of circumcision on male sexual function, pleasure and satisfaction, there were three systematic reviews: Morris & Krieger, (2013); Shabenzadeh et al, (2016); Tian et al, (2013), the last including a meta-analysis; and two RCTs: Kigozi et al, (2008) and Krieger et al, (2008). All found that circumcision has no adverse effect on male sexual function, pleasure or satisfaction, maybe even a slight beneficial effect. There is also a RCT showing that the female partners of circumcised men also tend to report an improvement (Kigozi et al, 2009).
Now they have been joined by another systematic review and meta-analysis: “Circumcision does not have [an] effect on premature ejaculation: A systematic review and meta-analysis” by researchers from Sichuan University in China (Yang et al. 2017). And what did they find?
Circumcision had no adverse effect on ease of achieving orgasm, it reduced pain on intercourse, and circumcised men were also less likely to suffer erectile dysfunction. Although there was some indication it increased time to orgasm, this was not by enough to make a difference to premature ejaculation. In short, circumcision has no adverse effect on the parameters studied, some modest positive effects, but does not cure premature ejaculation.
It does not look good for intactivists when every single study in the top two tiers of the hierarchy of evidence contradicts them. And more high quality studies keep being published. And, as the latest study (in common with Tian et al from China, and Shabenzadeh et al from Denmark) is by workers in a non-circumcising culture, who are not partisans in the debate, it cannot be accused of bias.
The science is in: All the best studies consistently show that circumcision does not harm sexual function, pleasure or satisfaction. It is high time that intactivists ended their denialism and accepted the science.
Bronsealer, G.A., Schober, J.M., Meyer-Bahlburg, H.F.L., T’Sjoen, G., Vlietinck, R., Hoebeke,P.B. (2013) Male circumcision decreases penile sensitivity as measured in a large cohort. BJU Int., 111(5), 820-7.
Frisch, M., Lindholm, M., Grønbæk, .M. (2011) Male circumcision and sexual function in men and women: a survey-based, cross-sectional study in Denmark. Int. J. Epidemiology, 40(5), 1367-81.
Kigozi, G., Watya, S., Polis, C.B., Buwembo, D., Kiggundu, V., Wawer, M.J., Serwadda, D., Nalugoda, F., Kiwanuka, N., Bacon, M.C., Ssempijja, V., Makumbi, F., Gray, R.H. (2008)
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., 101(1), 65-70.
Kigozi, G., Lukabwe, I., Kagaayi, J., Wawer, M.J., 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, R.H. (2009) Sexual satisfaction of women partners of circumcised men in a randomized trial of male circumcision in Rakai, Uganda BJU Int., 104(11), 1698-1701.
Krieger, J.N., Mehta, S.D., Bailey, R.C., Agot, K., Ndinya-Achola, J.O., Parker, C., Moses, S. (2008) Adult male circumcision: Effects on sexual function and sexual satisfaction in Kisumu, Kenya. J. Sex. Med., 5(11), 2610-22.
Morris, B.J., Krieger, J.N. (2013) Does male circumcision affect sexual function, sensitivity, or satisfaction?—A systematic review. J. Sex. Med., 10(11), 2644-57.
Shabanzadeh, D.M., Düring, S., Frimodt-Møller, C. (2016) Male circumcision does not result in inferior perceived male sexual function – a systematic review. Danish Medical Journal, 63(7), A5245.
Tian, W.L., Wang, J-Z., Wazir, R., Yue, X., Wang, K-J. (2013) Effects of circumcision on male sexual functions: a systematic review and meta-analysis. Asian J. Andrology, 15(5), 662-6.
Yang, Y., Wang, X., Bai, Y., Han, P. (2017) Circumcision does not have effect on premature ejaculation: A systematic review and meta-analysis. Andrologia, epub ahead of print.
News item for March 21, 2017
CIRCUMCISION DOES NOT AFFECT SENSATION OR PLEASURE, AND DOES NOT CAUSE LASTING TRAUMA: TWO NEW STUDIES.
Two papers published within weeks of each other will displease the intactivists. First researchers from the University of Illinois at Chicago published results of a study of men from the Dominican Republic. As HIV is a growing problem in Caribbean countries, the potential for circumcision to curb this epidemic is being examined there (it already is proving vital in Africa). In the course of a study into acceptability of voluntary male medical circumcision (VMMC), the researchers circumcised 454 men. Of the 362 who returned for follow up 98 % reported satisfaction with the outcome. Indeed, many went beyond mere satisfaction, two-thirds reporting an improvement in sexual function, and half reported an increase (yes, increase!) in sensation post-op. Fewer coital injuries were reported and, “Virtually all men were enthusiastic about recommending VMMC to their friends and reported better hygiene after the procedure.”
The second study knocks a hole in the notion that infant circumcision causes permanent brain changes. This idea has been circulated by intactivists for years, without any credible evidence, and recently took the form of an attempt to link circumcision to autism (which was swiftly discredited). In the latest study, researchers in Germany, a non-circumcising culture, used an objective approach. There is evidence that early trauma can affect a brain system called the limbic-hypothalamic-pituitary-adrenal (LHPA) axis, causing life-long effects. This includes affecting glucocorticoids, which can be detected in hair. The researchers hypothesised that if infant circumcision caused lasting trauma, then it should affect the LHPA axis, in turn leading to changes in glucocorticoids which can be detected in hair samples. So, with the aid of Jewish subjects, they examined hair samples from circumcised and non-circumcised men and found – no difference.
Of course no study is perfect, and intactivists will nit-pick at anything that does not fit their agenda. The Dominican study was of volunteers, so any men who valued their foreskins may have shunned it, leaving only those who did not value their foreskins. And the German study had a small sample size (9 circumcised, 11 not). But, as pointed out in a recent blog post by a well-read skeptic (https://forthesakeofscience.com/2017/03/10/science-moves-on-bodies-of-evidence/ ), science does not move on single studies, but on bodies of evidence. These two papers are part of a growing body of research confirming that circumcision has little or no effect on sexual pleasure or function. And they fit in with previous research by other workers. The Dominican study, for example, is matched by two randomised controlled trials in Africa which also found no adverse effect. One even found improvements in sensation and pleasure. Replicability is an important part of science. And the German study tallies with others in which no adverse psychological or behavioural effects were found.
When multiple studies, from different workers, approaching the subject from different angles, replicate previous findings, and converge on the same answer it becomes perverse to continue to maintain a contrary position. Irrespective of whether one agrees or not with infant circumcision, the science is clear. It does not detract from sexual pleasure, and it is high time intactivists stopped claiming otherwise.
The studies are:
Brito, M.O., Khosla, S., Pananookooln, S., Fleming, P.J., Lerebours, L., Donastorg, Y., Bailey, R.C. (2017) Sexual pleasure and function, coital trauma, and sex behaviors after voluntary medical male circumcision among men in the Dominican Republic. J. Sex. Med., epub ahead of print. https://www.ncbi.nlm.nih.gov/pubmed/28258953
Ullmann, E., Licinio, J., Barthel, A., Petrowski, K., Oratovski, B., Stalder, T., Kirschbaum, C., Bornstein, S.R. (2017) Circumcision does not alter long-term glucocorticoids accumulation or psychological effects associated with trauma- and stressor-related disorders. Translational Psychiatry, 7(3), 23 pages. http://www.nature.com/tp/journal/v7/n3/pdf/tp201723a.pdf