Introduction

Contemporary data consistently suggests that homosexuality is about 4–5% of the general population [1]. Similarly, in the USA, it has steadily been estimated to range between 3 and 4% [2]. However, same-sex sexual experiences do not necessarily determine sexual orientation [3, 4]; even men who identify as heterosexual have reported engaging in same-sex activities. Among men who identify as heterosexual, same-sex sexual experiences, including anal insertive sex, have been reported between 4 and 9% [4, 5]. Therefore, rather than use the term “gay,” the term men who have sex with men (MSM) is often used in medicine to refer to men who engage in sexual activities with other men, regardless of their sexual orientation [6•].

The lesbian, gay, bisexual, and transgender (LGBT) community commonly encounters obstacles that prevent appropriate access to health care [7]. These obstacles are often due to prejudice and discrimination these patients may have experienced in the past or are afraid to possibly experience when presenting, not only from the general population but also from the health care system itself [7]. Therefore, MSM may often delay consulting a specialist regarding their sexual dysfunction [8••]. They may be embarrassed because of the nature of their problem or may be reluctant to reveal their sexual orientation to the physician, not knowing what reaction they will receive [3, 8••].

Sexual medicine clinicians should be mindful and sensitive to variances in sexuality and in sexual practices [4]. This is important since the sex-related healthcare needs of these patients will differ from most heterosexual patients [6•].

Sexual Health and Dysfunction Among Men Who Have Sex with Men

Sexual health issues among MSM have received less attention than issues among heterosexual men [3]. The lack of publications and the scarcity of the literature addressing these issues demonstrate this [1, 9]. Moreover, MSM have commonly been excluded among multiple analyses and trials, causing a lack of evidence-based knowledge when assessing the effectiveness of treatments and prevalence of sexual dysfunction among them [1, 4]. Furthermore, limited information has been published regarding the experience and impact of sexual dysfunction among the partners of these men [10].

The prevalence of sexual dysfunction in MSM is high and is a complex interplay of biologic and psychosocial factors. This has been reported to range from 42 to 79% among gay men [9, 11, 12]. These dysfunctions can manifest in the form of erectile dysfunction (ED), anxiety about sex, pain during intercourse or anodyspareunia, lack of pleasure during sex, premature ejaculation, hypoactive sexual desire, anorgasmia, and other orgasmic difficulties. Sexual dysfunction in this community may also be associated with social and psychological issues. MSM that perceive or experiment discrimination in their social environment are more likely to report sexual dysfunction of any type [9]. Identity problems, including internalized homophobia, may cause intimacy issues provoking sexual dysfunction and even lack of sexual satisfaction [8••, 13].

The Importance of the Penis Among Gay Men

Penis shape and size receives attention in all cultures, but one can argue that it is even more idolized in gay culture. The penis is often associated to sexual attractiveness and masculinity. Its “double presence” in gay relationships or sexual encounters [14] can cause a degree of competition between men [4]. Any consternation with penile proportion can cause substantial distress [1, 14]. Furthermore, MSM are less likely to be in a monogamous relationship with a single partner and are more likely to have multiple partners, or to be in open or “monogamish” relationships. Therefore, any pathology or abnormality of the penis itself can cause added distress in this population particularly with potential new encounters.

MSM sexual roles can vary significantly. Some MSM may choose not to engage in anal intercourse. For those who do engage in anal intercourse, some may choose to strictly adhere to a particular role such as “top only” (anal-insertive) vs. “bottom only” (anal-receptive), while others may prefer one or the other, but engage in both roles (“versatile”) or enjoy both roles equally. A patient’s sexual priorities may differ based on their sexual role preference. It has been hypothesized that the sexual role among gay men at times may be dictated by penis size [15].

Erectile Dysfunction

The sexual well-being of men is closely associated and predicted by good erectile function [13]. ED is the most common sexual disorder in men; it is defined as the inability of a man to obtain or maintain an erection sufficient for sexual intercourse [16].

Receptive and insertive anal intercourse is more common among homosexual men when compared to heterosexual men [4, 5]. When compared to vaginal coitus, a stronger erection is needed to enter the anus and pass the sphincter muscles. Therefore, a potential relative increase in resistance may be present when entering the anus [17••, 18]. When trying to enter the anus, regardless of the desire of wanting to be penetrated, the anal sphincter muscles will close involuntarily, and a weaker erection may not get through [18]. It is necessary to take this into consideration when using a tool that assess ED in MSM.

The International Index of Erectile Function (IIEF), an accepted tool for assessing erectile function, has been considered the “gold standard of sexual function questionnaires” [19] but is designed for heterosexual men [20]. A modified and validated IIEF questionnaire has been created for the evaluation of ED in HIV-positive men [20]. Additional IIEF questionnaires tailored to assess erectile function among HIV-negative gay men have been presented and studied but are yet to be validated [4, 6•].

The prevalence of ED among MSM is variable. It is estimated to range between 6.3 and 57% among this population [4, 9, 11, 21•, 22•, 23]. Bancroft et al. [21•] compared erectile difficulties among a cohort of gay men (n = 1379) and heterosexual men (n = 1558). He found that it was more common for gay men to report ED than heterosexual men. The research showed that 43.1% of gay men reported ED in a time frame of 3 months prior to the administration of the survey, while 57.8% reported ED at any given time of their lives. In a meta-analysis between homosexual men and heterosexual men, Barbonetti et al. [24•] also demonstrated that there was a significantly higher risk of ED among the homosexual group (adjusted OR = 1.60, 95% CI 1.10–2.30; P = 0.01). In an Internet-based survey among medical students in the USA, ED was more common in homosexual men than in heterosexual men (24% vs. 12%, respectively); but after adjusting for marital/domestic partnership and relationship status, the difference did not maintain statistical significance, suggesting that relationship stability can be protective against ED [4].

Vansintejan et al. [22•] also presented that MSM who were in steady relationships were less likely to report ED, compared to those that were not in steady relationships. In this study, they used the Erection Quality Scale (EQS) which is a self-reported measurement assessing the quality of the erections [25]. It can be employed in both heterosexual and homosexual men, as well as in single men [25].

However, these two studies did not specify what being in a steady relationship was, nor if they were monogamous or in open relationships. Patients that are in a steady relationship may perhaps auto-select their sexual positions based on their erectile function and may suffer less dysfunction.

Shindel et al. [6•] conducted an Internet survey of men who have sex with men in which participants (n = 2640) completed the modified version of the International Index of Erectile Function previously validated in HIV-positive MSM. The following were significantly associated with greater odds of moderate to severe ED (IIEF-MSM erectile function domain score < 15): increasing age (OR = 1.495, 95% CI 1.353–1.653); voiding symptoms, IPPS score > 20 (OR = 1.426, 95% CI 1.135–1.792); HIV-positive status (OR = 1.521, 95% CI 1.117–2.071); prior use of erectogenic therapy, PDE5i (OR = 2.071, 95% CI 1.61–2.656); not engaging in anal insertive intercourse (OR = 2.600, 95% CI 1.785–3.787); low sexual life satisfaction (OR = 3.848, 95% CI 3.066–4.829); and not being in a steady relationship.

Shindel et al. [6•] also presented an association between ED and relationship status; but this association was not seen in Bancroft’s cohort [21•]. Therefore, conclusions regarding the role of a relationship on ED among gay men cannot be completely established nor understood. ED is also associated with men who have experienced discrimination because of their own MSM’s status [9].

Erectile dysfunction medications (EDMs), such as phosphodiesterase-5 inhibitors (PDE5i), have been reportedly used, off-label, among gay men with rates as high as 32.3% [26], with few gay men consulting a provider about their use [6•]. Despite not having a medical condition diagnosed, EDMs have become a popular drug of abuse due to its efficacy and easy use [26, 27]. Its recreational use alone is associated with increased sexual risk behavior [26]. Recreational use of EDMs may create unreasonable expectations with respect to erectile performance, and sexual performance anxiety can develop as a result of reduced confidence leading to psychogenic ED [27].

Sex and Drugs

EDMs are also commonly used with other recreational and illicit drugs to counter their known adverse effects on erection, especially in the setting of concomitant use of crystal methamphetamine, and to enhance sexual pleasure [26, 28]. It has been seen that stimulants are commonly associated with deleterious effects on erections [23]. In intense sexual partying and other high-risk sexual behaviors (where there is often implied illicit drug use), EDMs are used to facilitate erections [26, 28, 29]. In these settings, the use of EDMs is more about enabling the use of other drugs as well as to enhance and maximize their sexual experience rather than treatment for a preexisting erectile problem [26, 28, 30].

Amyl nitrates, commonly known as “poppers” are often used during anal intercourse. PDE5is are also commonly used with amyl nitrates or poppers [31], despite being contraindicated [28, 30]. Poppers are associated with an anal-receptive sexual role due to its relaxing effect on anal smooth muscle [31].

The Importance of Semen Among Gay Men

Semen itself has a symbolic significance among gay men and is also highly eroticized [32]. It is also seen as an intimate connection between two men and as “proof” of giving the partner an orgasm [33]. Ejaculation itself can play an important part in the sexual experience of men, particularly in MSM [34]. It can represent a more complete sexual experience given its powerful connotation, as well as evidence of sexual gratification [32, 33]. Semen is also associated with additional sexual practices in which the term cum play is included. This refers to the sexual practice that involves the sharing of semen among gay men. It includes ejaculating over the anus, rubbing semen over the anus, using semen as lubricant during masturbation or for digital/penile penetration, ingesting semen from the anus (felching), or transferring semen from one mouth to another (snowballing) [32, 35]. During “safe sex,” it is presumed that the exchange of semen is being averted with condom use, however this is not necessarily the case, since cum play has also been reported, as high, as one in five HIV-negative men during their most recent protected anal intercourse [32].

Premature Ejaculation

The International Society for Sexual Medicine (ISSM) defines premature ejaculation (PE) as sexual dysfunction characterized by (i) ejaculation that always or nearly always occurs prior to or within about 1 min of vaginal penetration (lifelong PE) or a clinically significant and bothersome reduction in latency time, often to about 3 min or less (acquired PE); (ii) the inability to delay ejaculation on all or nearly all vaginal penetrations; and (iii) negative personal consequences such as distress, bother, frustration, and/or the avoidance of sexual intimacy [36].

Using the ISSM’s definition, individuals who engage exclusively in homosexual activities cannot be diagnosed as having premature ejaculation [37]. However, there is “insufficient information to objectively define problematic early ejaculation in the context of oral sex, anal sex, and same-gender sexual activity,” so these practices were excluded from the definition [36]. Even though there is no standardized or validated definition for premature ejaculation among MSM, we will use the term premature ejaculation and rapid ejaculation interchangeably in MSM for the purposes of this review article.

The Premature Ejaculation Diagnostic Tool (PEDT) is a screening, self-reported questionnaire designed to assess the risk for PE [6•, 38]. A score of < 8 suggests a low likelihood of PE [38]. The PEDT has not been specifically validated for its use in MSM; however, it does not include any language that assumes vaginal coitus, so it is likely applicable to MSM [6•].

There are multiple ejaculatory disorders, but premature ejaculation is the disorder most reported [38]. Its prevalence in MSM is varied, ranging between 10.4 and 42.7% [9, 11, 12, 21•]. Bancroft et al. [21•] evaluated and compared self-reported rapid ejaculation (RE) among gay and heterosexual men. In this survey, gay men were less likely to report RE when compared to heterosexual men. However, in this study, no standardized or cut-off time was provided for the definition of rapid ejaculation. In another study among Portuguese men, it was demonstrated that homosexual men had 28% less probability (OR = 72, 95% CI 0.052–1.00; P = 0.05) of reporting premature ejaculation than heterosexual men [24•]. This reported difference between homosexual and heterosexual men has not been always noted and reported [4, 37].

Shindel et al. [6•] demonstrated greater odds of presenting with PE (PEDT > 9) in men with voiding symptoms, IPSS score > 20 (OR = 1.600, 95% CI 1.242–2.060); HIV-positive status (OR = 1.405, 95% CI 1.003–1.968); dissatisfaction with sexual life (OR = 2.148, 95% CI 1.676–2.753); and having fewer than six lifetime sexual partners.

The presence or absence of PE has also been associated with other variables. Gay men that have been circumcised after infancy are less likely to experience premature ejaculation when compared to those that were circumcised at infancy [39]. Other studies show that there is no association between “rapid ejaculation” and relationship status [21•]. However, it has been demonstrated that PE is associated with those that have perceived discrimination because of their own MSM’s status, as well as those that engage in multiple risky behaviors [9].

Peyronie’s Disease

The estimated prevalence of Peyronie’s disease (PD) in the USA ranges between 0.5 and 13.0% [40, 41]. This significant increase in prevalence in recent years is due to the increased recognition of this disease, along with the recently approved treatment modalities. Its pathophysiology is a combination of genetic predisposition and trauma, with an eventual common pathway involving fibrosis in the tunica albuginea [42]. This disorganized collagen deposition, mostly composed of type I/III, occurs in the tunica of the corpora cavernosa of the penis, forming the plaque and causing the development of the penile deformity [43, 44]. Very few men will report spontaneous resolution of the symptoms without any active treatment in comparison to the majority who will experience stable or worsening symptoms [44].

While penile curvature is the most common deformity, PD can present initially with penile pain, without any noticeable deformity [45]. It can also present with narrowing of the shaft of the penis, softness in some areas of the erected penis, and a palpable nodule or plaque [45]. This disease carries a negative psychosocial experience to patients that suffer from it [17••]. The deformity that arises from this condition can cause embarrassment and severe anxiety regarding their sexual function (including difficulties with erections and ejaculation) among affected men [43]. This can stress relationships and act as a barrier to satisfactory sexual relations [43]. Many MSM with PD avoid sexual contact resulting in a sense of isolation often associated with depression, since social stigmatization is augmented [43].

The Peyronie’s Disease Questionnaire (PDQ) is a self-reported validated questionnaire consisting of 15 items designed to measure the psychosexual consequences of PD and treatment outcomes; it contains 3 scales: (1) psychological and physical symptoms, (2) PD symptoms bother, and (3) penile pain [10, 46]. However, this questionnaire presents several limitations since it involves vaginal intercourse within the 3 months before taking the test. This in turn actively excludes patients who due to the severity of their condition are unable to engage in vaginal intercourse and those who purposely do not engage in vaginal intercourse, including homosexual and bisexual men [19].

Farrell et al. [17••] conducted a retrospective chart review among men with PD that self-identified as MSM (n = 27) and compared them to a random sample of non-MSM (n = 200) in clinic. This exhibited the first and only report of PD solely focusing on MSM. Following the onset of PD in MSM, 92.9% were self-conscious about the appearance of their penis, 92.5% were dissatisfied with the size of their penis, 50% reported a decreased frequency of sexual activity, and 31.3% reported a decrease in libido. Many similarities were noted among MSM and non-MSM, including identification of a traumatic event leading to the activation of PD, penile curvature, and penile shortening as the most common subjective presenting symptoms, as well as dorsal plaque location. Circumferential plaque was only reported in MSM. Additional distinctions were also noted, including penetrative sexual intercourse as the most common recognized factor for PD activation in MSM, followed by self-stimulation. Also, a greater proportion of MSM presented with penile deformity including narrowing, indentation, hourglass, and hinge as their primary complaint (11.1% MSM vs. 1.0% non-MSM, P = 0.01). In this study, it was also demonstrated that PD negatively affected the emotional status and their intimate relationships among MSM (89% and 45% of the studied subjects, respectively).

Among their cohort, Farrell et al. [17••] report that non-surgical treatment was administered to 88.9% of MSM and 76.5% of non-MSM. A greater proportion of MSM received oral therapy (70.4% vs. 27%); no differences were found in the use of injection therapy. Vacuum devices were non-differentially used (3.7% MSM vs. 14.5% non-MSM, P = 0.22), but traction devices were used more commonly between MSM (59.3% vs. 25.5% non-MSM, P < 0.01). Corrective surgery was performed in 29.6% of MSM and in 25% of non-MSM; with no differences in the surgical approaches performed. Farrell et al. [17••] also reports that the MSM cohort sought treatment from on average two other physicians prior to seeking treatment in their clinic. This may suggest more worry or anxiety from the disease or a more pro-active and invested patient in their sexual function.

Penile Fracture

Although the erect penis can withstand high pressures, it is still prone to fracture. This occurs secondary to a disruption of the tunica albuginea that covers the corpora cavernosum. The paired corpora cavernosa is dorsally located and separated by a dentate ligament; these are enclosed by a strong and thick tunica albuginea, which can tolerate high intracavernosal pressures generated during an erection [47]. Intracavernosal pressure can reach up to 1500 mmHg during an erection [48]. The tunica albuginea measures approximately 2 mm in thickness in the flaccid state and becomes much thinner at approximately 0.5 mm in the erect state. This makes the erect penis more prone to trauma and fracture [49].

The most common clinical presentation of penile fracture is penile hematoma, detumescence, and a “snapping” sound. If the patient presents with urethral bleeding and acute urinary retention, it may be indicative of some degree of urethral injury [50]. The penis typically deviates to the contralateral side that the fracture occurs, giving its distinctive eggplant deformity, and thus, highly suggestive of a penile fracture [49, 51].

Unilateral and bilateral corporal cavernosal fractures have been reported among MSM while engaging in anal insertive intercourse [52••]. In general, urethral fractures are associated with concomitant bilateral corporal fractures. However, only one concomitant urethral fracture has been reported in an MSM patient with bilateral corporal fracture with associated urethral bleeding [52••].

The most common position associated with penile fracture in the MSM population is “doggy style” [52••]. Fractures have also been reported with the patient on top, and the male partner on top [53, 54]. In the heterosexual population, penile fracture has also been reported with confirmed anal intercourse, demonstrating that anal intercourse is a risk factor for penile fracture [52••, 55].

Anal intercourse has also been implicated in penile re-fracture, as presented in two cases by Barros et al. [54]. The first case was a heterosexual male patient who presented initially with a unilateral corporal fracture while sustaining anal intercourse with a woman. Fifty-two months after repair, he presented with another penile fracture (unilateral corporal fracture in the same location as the initial fracture) while having insertive anal intercourse with a woman, both occasions on “doggy style” position. The second case was another heterosexual male who sustained a unilateral corporal fracture while engaging in anal intercourse with another man with the “man on top” position. The second fracture occurred 45 days after initial repair while having vaginal intercourse in the “doggy style” position. This time he sustained bilateral fractures of the corpora cavernosa.

Complications regarding sexual dysfunction after repair are common, but they have not been correlated with sexual orientation [52••, 53]. In MSM, complications after repair have been reported, including penile pain during intercourse, erectile dysfunction, formation of penile fibrotic nodule, penile curvature, premature or delayed ejaculation, low sexual desire, esthetic dissatisfaction, and subjective decrease in penile size [52••]. Voiding dysfunction and urethral fistula can occur if concomitant urethral injury is present; however, these complications have not been demonstrated in reports involving MSM [52••, 53].

Conclusion

Sexual dysfunction among MSM is common and can severely affect their quality of life. However, finding adequate appropriate care may be difficult. MSM have typically been excluded from most sexual studies to homogenize the populations studied. Studies specifically analyzing sexual function in MSM need to be conducted to better elucidate what is normal and what is pathologic.

Our current definitions and standards to evaluate sexual dysfunction are heteronormative and are not always applicable to MSM. There is a strong need for newer and more precise definitions and tools constructed for the gay community. This need is evident in the context of erectile and ejaculatory function. ED and ejaculatory dysfunction cannot be described solely based on vaginal penetration.

Only when we begin to accept that these differences matter and need to be evaluated differently can we begin to develop appropriate tools and tailor specific treatments, while being sensitive to the needs of this population will we begin to take one step in decreasing sexual healthcare disparities that gay men experience around the world.