A new study has found what thousands of circumcised men already know: that circumcision significantly reduces the sensitivity of the penis and has an adverse impact on male sexual functioning. The study, by researchers at the Department of Urology, Ghent University Hospital, Belgium, confirms earlier findings by Kim and Pang, Sorrells, Frisch and others that the foreskin is the principal source of sensation in the penis, that it facilitates all kinds of sexual activity and enhances sexual pleasure.
ABSTRACT
What’s known on the subject? And what does the study add? The sensitivity of the foreskin and its importance in erogenous sensitivity is widely debated and controversial. This is part of the actual public debate on circumcision for non-medical reason. Today some studies on the effect of circumcision on sexual function are available. However they vary widely in outcome. The present study shows in a large cohort of men, based on self-assessment, that the foreskin has erogenous sensitivity. It is shown that the foreskin is more sensitive than the uncircumcised glans mucosa, which means that after circumcision genital sensitivity is lost. In the debate on clitoral surgery the proven loss of sensitivity has been the strongest argument to change medical practice. In the present study there is strong evidence on the erogenous sensitivity of the foreskin. This knowledge hopefully can help doctors and patients in their decision on circumcision for non-medical reason.
Objectives To test the hypothesis that sensitivity of the foreskin is a substantial part of male penile sensitivity. To determine the effects of male circumcision on penile sensitivity in a large sample.
Subjects and methods The study aimed at a sample size of ≈1000 men. Given the intimate nature of the questions and the intended large sample size, the authors decided to create an online survey. Respondents were recruited by means of leaflets and advertising.
Results The analysis sample consisted of 1059 uncircumcised and 310 circumcised men. For the glans penis, circumcised men reported decreased sexual pleasure and lower orgasm intensity. They also stated more effort was required to achieve orgasm, and a higher percentage of them experienced unusual sensations (burning, prickling, itching, or tingling and numbness of the glans penis). For the penile shaft a higher percentage of circumcised men described discomfort and pain, numbness and unusual sensations. In comparison to men circumcised before puberty, men circumcised during adolescence or later indicated less sexual pleasure at the glans penis, and a higher percentage of them reported discomfort or pain and unusual sensations at the penile shaft.
Conclusions This study confirms the importance of the foreskin for penile sensitivity, overall sexual satisfaction, and penile functioning. Furthermore, this study shows that a higher percentage of circumcised men experience discomfort or pain and unusual sensations as compared with the uncircumcised population. Before circumcision without medical indication, adult men, and parents considering circumcision of their sons, should be informed of the importance of the foreskin in male sexuality.
Source: Bronselaer GA, Schober JM, Meyer-Bahlburg HF, T'sjoen G, Vlietinck R, Hoebeke PB. Male circumcision decreases penile sensitivity as measured in a large cohort. BJU Int. 2013 Feb 4. doi: 10.1111/j.1464-410X.2012.11761.x. [Epub ahead of print]
Abstract also accessible through Medline
Research by scientists in Slovenia has confirmed previous research, common knowledge and much personal testimony that the foreskin has an important sexual function. A paper by Simon Podnar, published in BJU International – the world’s leading urological journal – found that a reflex action known as the “penilo-cavernosus reflex” is rarely experienced by circumcised men. What this means in ordinary language is that circumcision, by excising the most important nerves of the penis, makes it less sensitive and less functional. The is result that men who retain their foreskins experience greater sexual excitability, better orgasm control and more pleasure. Writing in response to the article, Australia’s Greg Boyle welcomed the article for further developing the work of the late John Taylor and actually doing some objective, scientific investigation of the functions of the foreskin. This was a refreshing change from the ideologically-driven propaganda that pours out of the United States, more interested in exterminating foreskins than in understanding them. In fact, the foreskin is such a miracle of biological engineering that to destroy one without genuine need is an act of wanton vandalism. As Professor Podnar comments, “I see the prepuce as an ingenious device engineered to provide a strong sensory stimulation in a slippery environment”, the evolutionary purpose of which is to maximise the desire to reproduce.
“It is known that foreskin, but not glans penis, contains a high density of fine-touch mechanoreceptors. Clinically the penilo-cavernosus reflex provides information on function of the sacral nerves. The study demonstrated that in the majority of circumcised men this reflex cannot be elicited clinically, but can be measured neurophysiologically.”
Research by scientists in Slovenia has confirmed previous research by Dr John Taylor and others, common knowledge and much personal testimony that the foreskin plays an important role in male sexual response. A paper by Simon Podnar, published last year in BJU International – the world’s leading urological journal – found that a reflex action known as the “penilo-cavernosus reflex” is rarely experienced by circumcised men. What this means in ordinary language is that circumcision, by excising the most important nerves of the penis, makes it less sensitive and less functional; the result is that circumcised men experience less sexual excitability, less orgasm control and less pleasure. As Podnar writes, “The present study confirmed my previous observations that the penilocavernosus reflex is more difficult to elicit clinically in circumcised men. … The probable reason for this finding in circumcised men is the elimination of the most sensitive part of the penis (i.e. the foreskin), and to a lesser extent, desensitization of sensory receptors in the penile glans.” While the nerves of the foreskin are highly sensitive to light touch and gentle manipulation, those of the glans respond only to strong pressure, heat and pain.
These findings have significance for treatment of male sexual dysfunction, including premature ejaculation, as well as urinary and bowel control.
Source: Podnar S. Clinical elicitation of the penilo-cavernosus reflex in circumcised men . BJU Int 2012; 109: 582–5.
Writing in response to the article, Australia’s Greg Boyle welcomed the article for further developing the work of the late John Taylor and actually doing some objective, scientific investigation of the functions of the foreskin. It was refreshing to find a government sponsoring research aimed at improving our (highly inadequate) understanding of the anatomy and physiology of the foreskin, instead of merely cooking up yet more justifications for cutting it off. We will never understand the biology of the mature foreskin unless we can observe and study it in operation, as it were, and this will not be possible if it is routinely amputated in infancy.
The full text of Greg Boyle’s letter and Simon Podnar’s reply follows:
1. Greg Boyle’s letter
In a recent issue of the BJUI, Professor Podnar [1] reported his findings concerning the clinical elicitation of the penilo-cavernosus reflex in genitally intact men as compared with circumcised men. Previously, Taylor [2] had reported that, “Almost certainly, removal of the prepuce and its ridged band distorts penile reflexogenic functions but exactly how and to what extent still remains to be seen”. While Podnar’s study attempted to ascertain the magnitude of this reflexogenic disability, it is notable however that he used different stimulatory techniques in genitally intact vs circumcised men. As reported in his paper, Podnar tested the penilo-cavernosus reflex in intact men by squeezing the glans through the overlying foreskin, thereby stimulating the sensory receptors both within the foreskin itself as well as in the glans, whereas in circumcised men, the stimulus necessarily could only be applied to the glans (which is relatively devoid of fine-touch sensory receptors as compared with the inner foreskin with its dense innervation of Meisners’ corpuscles) [2–6]. This procedural discrepancy raises questions as to the validity of Podner”s clinical findings reported for circumcised and genitally intact men respectively.
Circumcision and premature ejaculation
In regard to PE, Podnar [1] repeated the common myth that “the glans is too sensitive”. To the contrary, PE with little or no sensation/feeling would suggest that the glans is not very sensitive at all. Many circumcised young men ejaculate prematurely but feel very little pleasurable sensation [7]. It would appear that PE may occur before there is much build-up of sexual excitement/tension, so that ejaculation is pretty much a “non-event”. Anecdotally, in the USA where most males have been subjected to routine neonatal circumcision, many young women have commented to their male partner, “Is that it?” Is it not more likely that it is precisely the lack of neurological control over the timing of ejaculation resulting from the severed neuronal circuitry after circumcision that is a major causal factor in PE? Indeed, Bollinger and Van Howe [8] pointed out that, “circumcised men are 2.56 times more likely to suffer from premature ejaculation, and, when the data were adjusted to include erectile dysfunction, that risk rose to 4.88 times”[9]. Moreover, “A recent multinational population survey using stopwatch assessment of the intravaginal ejaculation latency time (IELT) found that in Turkish men, the vast majority of whom are circumcised, had the shortest IELT [10,11].
This report is yet another small piece of the puzzle regarding the adverse effects of circumcision on sexual function [12,13], but cross-validation on much larger samples would seem important. There appears to be a paucity of research funds available to objectively investigate foreskin neurology, physiology, anatomy and sexual function, whereas formidable research resources appear to go to projects aimed at finding “justifications” for ablating the male foreskin. The whole area is still shrouded in myths and distorted by the fact that so much research is carried out in “foreskin-free zones” such as the USA.
Full text with references available from BJUI, 16 August 2012
2. Simon Podnar’s reply
There is a long lasting dispute about the physiological role of the prepuce in human. I see it as a tinny [sic] structure sitting at the evolutionary pinnacle, where our “selfish genes” fight their way into the next generation. Competition here is harsh, with no room for redundancy. I see the prepuce as an ingenious device engineered to provide a strong sensory stimulation in a slippery environment of a copiously lubricated vagina. Evolution achieved this by the tubular prepuce sliding during sexual activity over the conically shaped glans as far as the frenulum allows. Both, the prepuce and the frenulum, have rich mechanoreceptor innervation [1] sending a large sensory input to the brain. The goal of this mechanism is to achieve maximum procreative efficiency of the semen by optimising ejaculation in place and time. To achieve this, the brain also needs to be finely tuned with the genital sensory structures.
Intuitively, removal of the penile most sensitive genital structure would lead not only to reduced sexual sensation [2], but also to more difficult achievement of ejaculation. This reasoning – named by Professor Boyle “common myth”– logically leads to a thought that circumcision might be a useful therapy for premature ejaculation (PE). In line with this, in my paper [3] I cited a report that found a reduction in PE in three of seven patients [4] circumcised due to different penile pathology (e.g., phimosis, balanitis, condyloma, etc.). However, I have to admit that these penile conditions made this empirical support unconvincing. Professor Boyle, by contrast, cites studies showing higher frequency of PE [5] and shorter intravaginal ejaculation latency time (IELT) [6] in circumcised men. Of these, higher frequency of PE in the circumcised seems more convincing, as no effect of circumcision status on IELT could be found in an international study after the exclusion of Turkey [6]. Islamic or Asian background was suggested to be a risk factor for PE irrespective of circumcision status [7]. Nevertheless, anything but lower frequency of PE and longer IELT in the circumcised sounds contra intuitive, and needs explanation. The answer, I believe, is neuroplasticity – changes in the thresholds and connectivity that occur within the CNS after circumcision.
The method of the penilo-cavernosus reflex elicitation I used in my study [3] indeed activated only deep pressure and pain receptors [8] in the glans in the circumcised men. By contrast, in the intact men, the Meisners’ corpuscles [9] within the foreskin were also stimulated. However, I do not share the opinion of Professor Boyle that this reduces validity of my clinical findings. In both, the intact and circumcised men, I activated all the available sensory receptors at the tip of the penis, and I showed unequivocal differences in the elicitability of the penilo-cavernosus reflex in the two populations of men [3]. The finding is relevant both for using the reflex as a clinical test, and also for demonstration of possible functional differences. During sexual activity both the glans and the overlying foreskin are stimulated in intact men, as discussed above. However, I do agree that using this approach I could not differentiate absence of Meisners’ corpuscles in the foreskin or desensitisation of deep pressure and pain receptors in the glans as the reason for the reduced reflex elicitability found in the circumcised men.
Full text with references available from BJUI, 16 August 2012
In 2011 Circinfo.org reported a study by Danish researchers which found that circumcision reduces sexual satisfaction not only in circumcised men, but also in their female partners. The study by Morten Frisch et al, published in the International Journal of Epidemiology in October 2011, examined the association of male circumcision with a range of sexual measures in both sexes. It found that 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.”
Not surprisingly, these conclusions did not please circumcision advocates such as Brian Morris, who has set himself the daunting task of proving not only that circumcision is a “biomedical imperative for the 21st century” for various "health" reasons, but also that that the amputation of the foreskin has no impact at all on sexual function (and may even improve the operation and appearance of of the penis). He fired off a lengthy critique in reply, denouncing Frisch’s motives as much as his methodology. In his response (International Journal of Epidemiology, February 2012), Frisch not only debunks these criticisms, but reveals that following publication Morris sent emails to his supporters, urging them to send letters of complaint about the article to the editors of the journal, and (what is worse) disclosing the fact (meant to be kept confidential) that he was one of the original peer reviewers and had recommended that the paper not be published at all. Compromising the confidentiality of the peer review process in this manner is a serious breach of publication ethics. In his dignified reply to this blatant lobbying, Frisch highlights the implausibility of Morris’s attempts to portray himself as a “neutral and unbiased authority” on the “medical benefits” of circumcision, while attacking anybody who dares to disagree with him as ideology-driven anti-circumcision activists. He points out that Morris obviously has his own agenda, revealed in an impressive record of anti-foreskin activism going back to the 1990s. Frisch defends the conclusions of his own study as supported by good evidence and casting grave doubt on optimistic (?) claims that circumcision has no impact on sexual function.
Morten Frisch, Author’s Response to: Does sexual function survey in Denmark offer any support for male circumcision having an adverse effect?
Novel findings in our population-based survey, which had participation rates of 48% in men and 54% (not 40%, as wrongly mentioned by Morris et al.) in women, suggest, but by no means prove, the existence of non-trivial associations of male circumcision with frequent orgasm difficulties in men and with a range of frequent sexual difficulties in women, including orgasm difficulties, dyspareunia and a sense of incomplete sexual needs fulfilment. Morris et al. should not be blamed for feeling unconvinced by our findings. However, as these critics repeatedly refer to Morris’ pro-circumcision manifesto [1] as their source of knowledge, their objectivity must be questioned. Morris et al. express concern over possible overfitting in our logistic regression models because we included a number of potentially confounding variables that differed between circumcised and uncircumcised men and between women with circumcised and uncircumcised spouses. However, as seen in Tables 3–6 of our paper, models with adjustment only for age provided odds ratios (ORs) similar to those obtained in the fully adjusted model, suggesting that this is mostly a theoretical concern. Next, Morris et al. suggest that we should have corrected for multiple testing even though such statistical manoeuvres are, at best, unnecessary and, at worst, deleterious to sound statistical inference in most epidemiological studies. [2] Morris et al. also claim that prevalence ratios would have been more appropriate measures of association than ORs. However, despite Morris et al.’s firm statement to the contrary, there is nothing inherently inappropriate about using ORs in cross-sectional studies, even in situations with common outcomes. In such situations, however, ORs should not be misinterpreted as prevalence ratios. We would have been wrong to claim that our OR of 3.26 implied that frequent sexual difficulties were 3.26 times more common in women with circumcised spouses than in women with uncircumcised spouses. Nowhere in our paper did we interpret ORs in such a flawed manner. In accordance with the cited reference [3] we simply noted that frequent sexual difficulties were more common in women with circumcised spouses and that the associated fully adjusted OR was 3.26.
Next, Morris et al. argue that our finding of considerably higher rates of frequent orgasm difficulties in (partially) circumcised than uncircumcised Danish men (11 vs 4%, OR1/43.26) may not apply in countries where circumcision means complete amputation of the foreskin. This may well be the case. If partial amputation of the foreskin truly entails frequent orgasm difficulties in a noticeable proportion of men (as experienced by 11% of circumcised men in our study), comparable proportions may well be larger and associated ORs even higher in countries where circumcised men experience greater tissue loss due to more extensive circumcision procedures. Obviously, more data are needed from rigorous studies using carefully constructed questionnaires. The questionnaires used to assess potential sexual problems in the two cited randomized controlled trials in Kenya and Uganda were not presented in detail in the original publications. [4,5] Rather than blindly accepting such findings as any more trustworthy than other findings in the literature, it should be recalled that a strong study design, such as a randomized controlled trial, does not offset the need for high-quality questionnaires. Having obtained the questionnaires from the authors (RH Gray and RC Bailey, personal communication), I am not surprised that these studies provided little evidence of a link between circumcision and various sexual difficulties. [4,5] Several questions were too vague to capture possible differences between circumcised and not-yet circumcised participants (e.g. lack of a clear distinction between intercourse and masturbation-related sexual problems and no distinction between premature ejaculation and trouble or inability to reach orgasm). Thus, non-differential misclassification of sexual outcomes in these African trials probably favoured the null hypothesis of no difference, whether an association was truly present or not.
Morris et al. should be commended for their creative attempt to dismiss the higher prevalence of frequent dyspareunia in women with circumcised (12%) than uncircumcised (4%) spouses (ORs between 4.17 and 9.00). They suggest that Danish women with circumcised spouses may be so psychologically troubled by the shape of their spouse’s penis that it might result in painful intercourse. A more plausible explanation would be that reduced penile sensitivity may raise the need among some circumcised men for more vigorous and, to some women, painful stimulation during intercourse in their pursuit of orgasm.
Two of the authors, Morris and Waskett, both internationally recognized circumcision activists, [6,7] forget to declare their conflicts of interest. Even in situations that are out of context, Morris promotes himself as a neutral ‘authority on the extensive medical benefits of this simple surgical procedure’, [8] whereas at the same time he argues that neonatal male circumcision ‘should be made compulsory’ and that ‘any parents not wanting their child circumcised really need good talking to’. [9] In contrast, we conducted our survey without setting up any a priori hypotheses, because the limited and inconclusive literature on possible sexual consequences of circumcision would permit almost any imaginable a priori hypothesis. We had no intent to prove an already known ‘truth’ or disprove its contradiction. It is ironic that Morris et al. question the credibility of our findings, postulating that I have an ‘active involvement in opposition to male circumcision’. I have never expressed any objection, ethical, medical or other, against male circumcision as such. Unlike Morris, who believes that ‘circumcision is a biomedical imperative for the 21st century’, [1] I could not care less whether fully informed, healthy adults choose to get circumcised or not. Likewise, when foreskin pathology is present (which does not include the physiological tightness of the foreskin experienced transiently by most boys), and the problem cannot be treated conservatively, preputioplasty or partial circumcision may be a relevant solution, even in minors and others who are unable to consent to the operation. However, because ethical discussions about ritual circumcision are sometimes distorted by strong personal views, I openly declared that I have participated in national debates over ethical issues surrounding male and female circumcision.
Like in critical letters to the editor following other recent studies that failed to support their agenda, [10–12] Morris et al. air a series of harsh criticisms against our study. As seen, however, the points raised are not well founded. It seems that the main purpose, as with prior letters, is to be able in future writings to refer to our study as an ‘outlier study’ or one that has been ‘debunked’, ‘rejected by credible researchers’ or ‘shown wrong in subsequent proper statistical analysis’. This in spite of the fact that our study was carried out using conventional epidemiological and statistical methods, underwent peer-review and was published in an international top-ranking epidemiology journal.
I would like to thank the IJE editors for withstanding the pressure from one particularly discourteous and bullying reviewer who went to extremes to prevent our study from being published. After the paper’s online publication, I have received emails from colleagues around the world who felt our contribution was useful and potentially important. One colleague informed me that the angry reviewer was the first author of the above letter to the editor. In an email, Morris had called people on his mailing list to arms against our study, openly admitting that he was the reviewer and that he had tried to get the paper rejected. To inspire his followers, Morris had attached his two exceedingly long and aggressive reviews of our paper (12,858 words and 5291 words, respectively), calling for critical letters in abundance to the IJE editors. Breaking unwritten confidentiality and courtesy rules of the peer-review process, Morris distributed his slandering criticism of our study to people working for the same cause. Rather than resorting to such selective distribution among friends, Morris should make both reviews freely available on the internet by posting them in their entirety on his pro circumcision homepage (www.circinfo.net). Alternatively, interested readers should feel free to request them from me at the e-mail address above. Despite poorly founded criticisms and attempts at obstruction our findings suggest that male circumcision may be associated with hitherto unappreciated negative sexual consequences in a non-trivial proportion of men and women. Further carefully conducted studies are needed.
1. Morris BJ. Why circumcision is a biomedical imperative for the 21st century. Bioessays 2007;29:1147–58.
2. Perneger TV. What’s wrong with Bonferroni adjustments. Br Med J 1998;316:1236–38.
3. 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.
4. 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.
5. 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.
6. Circleaks. http://circleaks.org/index.php?title1/4Brian_Morr is (8 August 2011, date last accessed).
7. Circleaks. http://circleaks.org/index.php?title1/4Jake_H._ Waskett (8 August 2011, date last accessed).
8. Morris BJ. Renin, genes, and beyond: 40 years of molecular discoveries in the hypertension field. Hypertension 2011;57:538–48.
9. YouTube. http://www.youtube.com/v/7yDvL4hNny4 (8 August 2011, date last accessed).
10. Morris BJ, Wodak A. Circumcision survey misleading. Aust N Z J Public Health 2010;34:636–37.
11. Waskett JH, Morris BJ, Weiss HA. Errors in meta-analysis by Van Howe. Int J STD AIDS 2009;20:216–18.
12. Waskett JH, Morris BJ. Fine-touch pressure thresholds in the adult penis. BJU Int 2007;99:1551–52.
SOURCE: Morten Frisch, Author’s Response to: Brian Morris et al, Does sexual function survey in Denmark offer any support for male circumcision having an adverse effect? International Journal of Epidemiology 41 (1), February 2012, 312-314. Morris’s letter in reply can be read in the same issue of the journal.
The original article was Morten Frisch, Morten Lindholm and Morten Grønbæk, Male circumcision and sexual function in men and women: A survey-based, cross-sectional study in Denmark, International Journal of Epidemiology 40 (5), October 2011, 1367-1381.
In two recent papers, psychology professor Dr Greg Boyle considers the physical and mental harms of non-therapeutic circumcision. After reviewing the extensive literature in medical and scientific journals, he finds that not only are the risks and complications of the surgery greater than commonly believed, but also that the harms of foreskin loss itself (i.e. without complications) are far more extensive than most people think. These are very harms of circumcision that are completely ignored by circumcision advocates and bureaucratic policy makers (such as the US Centers for Disease Control), who talk narrowly about “risks vs benefits” and ignore the usefulness of the foreskin (contrary to what the Jewish philosopher Maimonides stated) and regard the removal of a healthy foreskin as no different from the removal of a diseased appendix. Professor Boyle particularly rejects recent claims by Morris and Krieger that circumcision “makes no difference” to sexual function as implausible and contradicted by the evidence, and notes that other experts have found serious flaws in their analysis.
ABSTRACT Non-therapeutic infant male circumcision is a permanent surgical alteration to the penis that may cause significant physical, sexual and psychological harm. Physical harms include unintended adverse effects of the surgery itself (e.g., complications such as bleeding, infection, excessive removal of foreskin leaving insufficient shaft skin to accommodate erections, etc.), as well as the inherent loss of healthy, functional tissue. Sexual harms that necessarily follow from circumcision include the loss of all sensation in the foreskin itself, and the loss of all sexual functions that involve the physical manipulation of the foreskin. Additional sexual harms that may follow circumcision include reduced sexual sensation in the remaining penile structures, difficulty with masturbation, increased chafing in both the circumcised man and his sexual partner, as well as reduced overall psychosexual/psychological tension relief and subjective satisfaction. Psychological harms include short-term trauma as well as the potential for long-term emotional disturbances, including sadness, frustration, distress, and anger—akin to post-traumatic stress disorder (PTSD). In this paper, the extent and severity of these various harms are considered and it is argued that they are more serious and more widespread than is commonly believed.
Boyle, G. (2015) Circumcision of Infants and Children: Short-Term Trauma and Long-Term Psychosexual Harm. Advances in Sexual Medicine, 5, 22-38. doi: 10.4236/asm.2015.52004.
A paper in a recent issue of Advances in Sexual Medicine shows that the literature survey in which Morris and Krieger claims to show that circumcision makes no difference to sexual experience is deeply flawed and inconsistent with the full range of the evidence. The abstract reads as follows:
Morris and Krieger (2013) have argued that male circumcision does not impact adversely on sexual sensation, satisfaction, and/or function. In the present paper, it is argued that such a view is untenable. By selectively citing Morris’ own non-peer-reviewed letters and opinion pieces purporting to show flaws in studies reporting evidence of negative effects of circumcision, and by failing adequately to account for replies to these letters by the authors of the original research (and others), Morris and Krieger give an incomplete and misleading account of the available literature. Consequently, Morris and Krieger reach an implausible conclusion that is inconsistent with what is known about the anatomy and functions of the penile foreskin, and the likely effects of its surgical removal.
Gregory J. Boyle, Does Male Circumcision Adversely Affect Sexual Sensation, Function, or Satisfaction? Critical Comment on Morris and Krieger (2013). Advances in Sexual Medicine, 31 March 2015.
Further information and other research
Research by Jen Bossio and colleagues on the nature of penile sensation in circumcised and normal males is to be welcomed. However uncertain or provisional some of their conclusions may be, their work represents a genuine attempt to shed light on an under-researched area of physiology and should stimulate further investigation. In the immediate term their research has provoked a strong dissent from Brian Earp, who argues that their principal conclusion – that circumcision makes little or no difference to penile sensitivity – is neither supported by their own evidence nor consistent with previous research on this question.
A major cause of this disagreement may be that Bossio et al’s research methodology takes the foreskin and penis as separate structures whose properties can be analysed individually, while Earp regards them as elements of a single structure that produce the best results if they work together and which, therefore, should be analysed as a dynamic ensemble. There is sense in this view: when it comes to actual sexual activity, most uncircumcised men are not particularly interested in whether their foreskin, glans or penis shaft is more sensitive to light touch, heat or pain, but rather in the sensations arising from the movement of the foreskin over the glans, or from the friction between the inner foreskin (retracted and everted with erection) and whatever flesh or device is providing the pressure. As nineteenth century advocates of circumcision as a remedy for masturbation warned, it was the mutual stimulation of foreskin and glans that was the problem. The weakness of Bossio’s research methodology is that it examined the penis as a series of static and disconnected objects rather than as a system in motion.
In other words, the problem with these touch tests (and it also affects the Sorrels study, which never got to the heart of the matter) is that they bear no relation to what actually happens during sex. In any sexual activity (wanking, oral, intercourse or whatever) the foreskin is under pressure and stimulated from both sides: from whatever is touching it on the outside, and by the pressure of the glans and shaft on the other side. Since foreskin and glans work together and mutually stimulate each other it is unrealistic to try to separate them and ask which makes the greater contribution to sexual sensation. They need to be studied together in actual situations where sex is taking place.
So where should researchers go from here? One possibility is suggested by an informal experiment conducted by New Zealand pathologist Ken McGrath (University of Technology, Auckland) some years ago. He arranged for several adult volunteers (not circumcised) to masturbate to orgasm. In a subsequent session he deadened their foreskins with a local anaesthetic, got them to masturbate again, and to describe the sensations they experienced in comparison with normal conditions on the previous occasion. The results were striking. All subjects took far longer to reach orgasm and reported:
All participants found the anaesthetized prepuce experience far less enjoyable, lacking the intense sensation they normally experienced, and rather unsatisfying in comparison.
It could not be claimed that this small experiment to be in any way decisive. The sample size was absurdly small, the methodology was unapproved, and it might not have been possible fully to isolate the nerves of the foreskin in such as way as would correspond to the effects of circumcision. Nonetheless, the exercise is suggestive as a pilot study, and offers a different approach to the question – one that requires no expensive equipment or preparations, and carries no risk of harm to any of the participants. In a university research environment with the full range of medical specialists, including anaesthetists, it should be possible to overcome the methodological difficulties, and recruit sufficient volunteers to secure a robust result.
Further information
Brian Earp, Infant circumcision and adult penile sensitivity: implications for sexual experience. Trends in Urology and Men’s Health 7 (4), July-August 2016.
Abstract: A recent study reported that neonatal circumcision is not associated with changes in adult penile sensitivity, leading to viral coverage in both traditional and online media. In this commentary the author questions the conclusions drawn from the study and explores the relationship between objective assessments of penile sensitivity and subjective sexual experience and satisfaction. The author concludes with suggestions for improving future research.
Circumcision, sexual function and penis sensitivity: Bossio study ctiticised
Quotes on circumcision and foreskin function
Sexuality and sexual function at Circumstitions.com