The pathophysiology of delayed ejaculation

The Association Between Atypical Masturbation and Male Sexual Dysfunction: A Study Based on Men in Heterosexual Relationships

We aimed to establish the prevalence of atypical masturbation in the general population and explore the association between atypical masturbation and male sexual dysfunction in heterosexual males. Atypical masturbation refers to stimulation significantly distinct from that encountered during partnered sexual activity. We posted questionnaires that contained the abridged International Index of Erectile Function (IIEF-6) and the premature ejaculation diagnostic tool on social media in China. We collected 2743 valid questionnaires from December 9, 2020, to April 18, 2021. We found that the prevalence of atypical masturbation in the general population was 10.97%. Men with atypical masturbation had lower IIEF-6 scores and higher rates of erectile dysfunction (ED) than men with typical masturbation. The prevalence of premature ejaculation and estimated intravaginal ejaculatory latency time were not significantly different among men with different patterns of masturbation. Our study demonstrated that atypical masturbation is associated with ED, and a clinician dealing with sexual issues should inquire more fully about masturbation patterns than has been done to date.

A population analysis of delayed ejaculation using a claims database: characteristics and national trends in prevalence, incidence, and pharmacotherapy

We investigated the prevalence, incidence, and rates of pharmacological treatment of delayed ejaculation using the TriNetX Diamond Network. We included all men evaluated in the inpatient, outpatient, and emergency settings. Prevalence was determined by comparing the number of men diagnosed with delayed ejaculation to the entire population. Incidence was determined by comparing the number of men diagnosed with delayed ejaculation without a prior diagnosis to the overall population without a prior diagnosis. Rates of pharmacologic treatment were calculated by comparing the number of men who received a prescription to the total number of men with delayed ejaculation. Trends in prevalence and incidence were compared using six-month intervals, while trends in pharmacologic treatment were compared using one-year intervals. A total of 23,164 adult males were diagnosed with delayed ejaculation from 2013 to 2019. During the final six-month interval (July to December 2019), 2,747 of 16,496,744 men received a delayed ejaculation diagnosis, and 1,375 of 16,488,270 men without a prior diagnosis were diagnosed with delayed ejaculation. In 2019, only 916 of 4,733 (19.4%) men diagnosed with delayed ejaculation received any prescription, with the most common being testosterone (9.5%), bupropion (6.6%), and buspirone (2.3%). Prevalence, incidence and pharmacologic treatment all had increasing trends.

Regular penis-root masturbation: A promising behavioral treatment method for lifelong premature ejaculation

AIM

We aimed to determine the effectiveness of penis-root masturbation (PRM), a newly defined behavioral therapy (BT) technique, in patients with unsuccessful medical treatment due to premature ejaculation (PE).

MATERIAL AND METHODS

The study included 35 patients aged 25-43 years, who were diagnosed with lifelong PE. Patients and their partners were informed about the PRM technique and asked to practice PRM three times a week for three months, with or without sexual intercourse. The patients' Premature Ejaculation Diagnostic Tool (PEDT) scores and intravaginal ejaculatory latency time (IELT) were recorded and compared before PRM training (T0) and at the third (T3) month after the start of PRM training.

RESULTS

The mean±SD PEDT scores were 16.26±1.94 at T0, 10.63±1.14 at T3. When compared to T0, the PEDT values at T3 were significantly lower (P=0.021). In terms of IELT, the mean T3 values (192.43±56.71) were significantly longer (P=0.035) than at T0 (50.43±13.84seconds).

CONCLUSION

PRM BT shows promise for lifelong PE patients who do not benefit from or discontinue to pharmacotherapy. Larger prospective trials are required to confirm these findings.

Understanding and treating ejaculatory dysfunction in men with diabetes mellitus

Diabetes mellitus is a rapidly rising metabolic disorder with important systemic complications. Global figures have demonstrated the prevalence of diabetes mellitus has almost quadrupled from 108 million in 1980 to 422 million in 2014, with a current prevalence of over 525 million. Of the male sexual dysfunction resulting from diabetes mellitus, significant focus is afforded to erectile dysfunction. Nevertheless, ejaculatory dysfunction constitutes important sexual sequelae in diabetic men, with up to 35%-50% of men with diabetes mellitus suffering from ejaculatory dysfunction. Despite this, aspects of its pathophysiology and treatment are less well understood than erectile dysfunction. The main disorders of ejaculation include premature ejaculation, delayed ejaculation, anejaculation and retrograde ejaculation. Although ejaculatory dysfunction in diabetes mellitus can have complex multifactorial aetiology, understanding its pathophysiological mechanisms has facilitated the development of therapies in the management of ejaculatory dysfunction. Most of our understanding of its pathophysiology is derived from diabetic animal models; however, observational studies in humans have also provided useful information in elucidating important associative factors potentially contributing to ejaculatory dysfunction in diabetic men. These have provided the potential for more tailored treatment regimens in patients depending on the ejaculatory disorder, other co-existing sequelae of diabetes mellitus, specific metabolic factors as well as the need for fertility treatment. However, evidence for treatment of ejaculatory dysfunction, especially delayed ejaculation and retrograde ejaculation, is based on low-level evidence comprising small sample-size series and retrospective or cross-sectional studies. Whilst promising findings from large randomised controlled trials have provided strong evidence for the licensed treatment of premature ejaculation, similar robust studies are needed to accurately elucidate factors predicting ejaculatory dysfunction in diabetes mellitus, as well as for the development of pharmacotherapies for delayed ejaculation and retrograde ejaculation. Similarly, more contemporary robust data are required for fertility outcomes in these patients, including methods of sperm retrieval and assisted reproductive techniques in retrograde ejaculation.

Psychological distress, emotion regulation, neuroticism, and sexual relationship on patients with temporary ejaculation failure in vitro fertilization-embryo transfer treatment

Objective

Temporary ejaculation failure on the oocyte retrieval day might leading interruption of the oocyte retrieval procedure. The present study aims to understand the psychosocial factor that affects men with temporary ejaculation failure (TEF) in Vitro fertilization-embryo transfer (IVF-ET) patients, and thus provide new ideas for optimal clinical treatment.

Study design

In a prospective study, the male patients during IVF treatment in a reproductive center of a tertiary hospital in Shandong were divided into two groups, 70 men with TEF and 79 normal controls. General population sociology and clinical disease were investigated, and the Kessler 10 scale, emotion regulation questionnaire, big five inventory questionnaire, and sex subscale of marriage quality were used to assess the psychological distress, emotion regulation, neuroticism, and satisfaction with sexual life.

Results

The scores of perceived distress and neuroticism of the TEF group were higher than the non-TEF group (p < 0.001), and cognitive reappraisal and sexual relationship were significantly lower than those in the non-TEF group (p < 0.001). Psychological distress (OR 1.130, p = 0.031) and neuroticism (OR 1.096, p = 0.050) were risk factors for TEF, while cognitive reappraisal (OR 0.883, p = 0.004) and sexual relationship (OR 0.712, p < 0.001) was protective factors.

Conclusion

The present study demonstrates that psychosocial factors influence TEF in IVF-ET patients, which provides the basis for the prevention of the occurrence of TEF in a male undergoing IVF-ET.

Neurons for Ejaculation and Factors Affecting Ejaculation

Simple Summary

Sexual dysfunctions are rarely discussed in our current society. Males experience different sexual dysfunctions, including erectile, infertility, and ejaculatory dysfunctions. In this review only the ejaculatory dysfunction will be discussed. Ejaculation is defined as the ejection of contents collectively from the vas deferens, seminal vesicle, prostate and Cowper’s glands. It is completely controlled by a population of neurons present in the lumbar spinal cord. The presence of lesion in these neurons ceases the ejaculatory behavior in males. This population of neurons was first identified in rats; however, recently it was confirmed that these neurons are present in human males as well. The issues are known as ejaculatory dysfunction. The following are the different types of ejaculatory dysfunctions: early ejaculation, ejaculation into the urinary bladder, late ejaculation and no ejaculation.

Abstract

Ejaculation is a reflex and the last stage of intercourse in male mammals. It consists of two coordinated phases, emission and expulsion. The emission phase consists of secretions from the vas deferens, seminal vesicle, prostate, and Cowper’s gland. Once these contents reach the posterior urethra, movement of the contents becomes inevitable, followed by the expulsion phase. The urogenital organs are synchronized during this complete event. The L3–L4 (lumbar) segment, the spinal cord region responsible for ejaculation, nerve cell bodies, also called lumbar spinothalamic (LSt) cells, which are denoted as spinal ejaculation generators or lumbar spinothalamic cells [Lst]. Lst cells activation causes ejaculation. These Lst cells coordinate with [autonomic] parasympathetic and sympathetic assistance in ejaculation. The presence of a spinal ejaculatory generator has recently been confirmed in humans. Different types of ejaculatory dysfunction in humans include premature ejaculation (PE), retrograde ejaculation (RE), delayed ejaculation (DE), and anejaculation (AE). The most common form of ejaculatory dysfunction studied is premature ejaculation. The least common forms of ejaculation studied are delayed ejaculation and anejaculation. Despite the confirmation of Lst in humans, there is insufficient research on animals mimicking human ejaculatory dysfunction.

Metabotropic Glutamate Receptor Subtype 7 Is Essential for Ejaculation

Metabotropic glutamate receptor subtype 7 (mGluR7) is a member of the group III mGluRs, which are negatively coupled to adenylate cyclase via Gi/Go proteins and localized to presynaptic active zones of the mammalian central nervous system (CNS). To elucidate the mechanism of impaired reproductivity of mGluR7 knockout (KO) mice, we investigated sexual behavior in this line, which exhibits ejaculatory disorder, although with normal sexual motivation and erectile function. To identify the site of action within the CNS responsible for the effect of mGluR7 on ejaculation, we then used a para-chloroamphetamine (PCA)-induced ejaculation model. Intrathecal administration of the mGluR7-selective antagonist 6-(4-methoxyphenyl)-5-methyl-3-pyridin-4-ylisoxazolo[4,5-c]pyridin-4(5H)-one (MMPIP) into the lumbosacral spinal cord inhibited PCA-induced ejaculation. Immunohistochemistry revealed mGluR7-like immunoreactivity (LI) expressed in the same area where lumbar spinothalamic (LSt) cells regulate the parasympathetic ejaculatory pathway. At high magnification, the apposition of mGluR7-LI puncta and neuronal nitric oxide synthase (nNOS)-LI-positive putative parasympathetic preganglionic neurons was evident. These results indicate that mGluR7 in the lumbosacral spinal cord regulates ejaculation by potentiating the excitability of parasympathetic preganglionic neurons. The ejaculatory disorder is a major issue in the field of male reproductive function. Erectile dysfunction (ED) can be treated by phosphodiesterase type 5 inhibitors like sildenafil (Viagra®), but the ejaculatory disorder cannot. Lack of understanding of the ejaculatory mechanism hinders the development of therapies for ejaculatory problems. This study is the first to demonstrate that mGluR7 regulates ejaculation and the results provide insight into the mechanism of ejaculation as well as a strategy for future therapies to treat ejaculatory disorders in humans.

Regular penis-root masturbation, a novel behavioral therapy in the treatment of primary premature ejaculation

The primary premature ejaculation (PPE) is a common male sexual disorder. We proposed a novel behavioral therapy for PPE through regular penis-root masturbation (PRM). Nine heterosexual men with PPE completed the self-controlled study. After a 3-month PRM training, the median intravaginal ejaculatory latency time (IELT) increased from 60 s to 180 s (P = 0.018), and the mean Premature Ejaculation Diagnostic Tool (PEDT) score decreased from 14.8 ± 3.7 to 12.8 ± 4.1 (P = 0.074). Five out of eight patients had the prolonged dorsal nerve somatosensory evoked potential (DNSEP). The results suggest that PRM has a short-term therapeutic effect. Randomized controlled trials are needed to validate the efficacy.

Male Ejaculatory Endophenotypes: Revealing Internal Inconsistencies of the Concept in Heterosexual Copulating Rats

Distinct manifestations of sexual behavior are conceived as separate phenotypes. Each sexual phenotype is assumed to be associated with a characteristic brain. These notions have justified the phenotyping of heterosexual copulator males based upon their ejaculation's latencies (EL) or frequencies (i.e., cumulative ejaculation number; EN). For instance, men and male rats showing premature, normal or retarded ejaculation are assumed to be distinctive endophenotypes. This concept, nonetheless, contradicts past and recent evidence that supports that sexual behavior is highly variable within each sex, and that the brain sexual functional morphology represents an intricate sexual phenotypic mosaic. Hence, for ejaculatory male endophenotypes to be considered as a valid biological concept, it must show internal consistency at various levels of organization (including genetic architectures), after being challenged by intrinsic and/or extrinsic factors. We then judged the internal consistency of the presumed ejaculatory endophenotypes by assessing whether copulatory behavior and the expression of copulation relevant genes and brain limbic structures are specific to each of the presumed EL- or EN-ejaculatory endophenotypes. To do this, copulating male rats were first phenotyped in groups consistently displaying short, average or long ejaculation latencies or very high, high, average, low or very low EN, based in their copulatory performance. Then, the internal consistency of the presumed EL- or EN-endophenotypes was tested by introducing as covariates of phenotyping other copulatory parameters (e.g., number of intromissions) in addition to EL or EN, or by analyzing the expression levels of genes encoding for estrogen receptor alpha, progesterone receptor, androgen receptor, aromatase, DNA methyl-transferase 3a and DNA methyl-transferase 1 in the amygdala, medial preoptic area, ventromedial hypothalamus and olfactory bulb. We found that even though there were group-level differences in all the variables that were studied, these differences did not add-up to create the presumed EL- or EN-ejaculatory endophenotypes. In fact, the extensive overlapping of copulatory parameters and expression levels of copulation relevant genes in limbic structures across EL- or EN-phenotyped copulating male rats, is not consistent with the hypothesis that distinct ejaculatory endophenotypes exist and that they are associated with specific brain characteristics.

Piper auritum Kunth (Piperaceae) improves the sexual performance of sluggish male rats through enhancing ejaculation

ETHNOPHARMACOLOGICAL RELEVANCE

Piper auritum Kunth is employed as an aphrodisiac in the traditional medicine, but corroborative evidence for such effect is scarce.

AIM OF THE STUDY

The pro-sexual effect of an aqueous extract of P. auritum and its possible mechanisms were analyzed in two paradigms of male sexual function.

MATERIAL AND METHODS

Effects of an aqueous extract of P. auritum (PA, single administration) were investigated in the fictive ejaculation, and copulatory behavior paradigms in sexually sluggish male rats. WAY 100635 (antagonist of 5-HT_1A receptors), atosiban (antagonist of oxytocinergic receptors), L-NAME (inhibitor of the nitric oxide synthase) and baclofen (antagonist of GABA_B receptors) were used as pre-treatments in order to investigate the role of different neurotransmitter systems in PA actions. Chemical profile of PA was determined by Gases Chromatography and Ultra Performance Chromatography-Electrospray Ionization-Masses Spectrometry (UPLC-ESI-MS).

RESULTS

In males with retarded ejaculation, PA stimulated ejaculatory behavior and recovered electromyographic activity of pelvic musculature participating in seminal emission and ejaculation. All pre-treatments blocked stimulating effects of PA on the fictive ejaculation; additionally WAY 100635 interfered with PA actions on ejaculatory behavior. Safrol, apigenin dimethylether, myristicin, vaccihein A, sakuranin and sakuranetin flavonoids, were main constituents of PA, with possible participation in its pro-sexual effects.

CONCLUSIONS

Pro-sexual effects of P. auritum elicited at level of ejaculation were mediated by several neurotransmitter systems, among which serotonin and its 5-HT_1A receptors play an important role. Present findings support P. auritum reputation as an aphrodisiac, with potential use in delayed ejaculation disorder.

Contemporary management of ejaculatory dysfunction

Although erectile dysfunction is the most common disorder of male sexual health, ejaculatory dysfunction is the most common form of sexual dysfunction experienced by men. Ejaculatory dysfunction covers a broad range of disorders that we have divided into four main categories: premature ejaculation, delayed ejaculation (DE)/anorgasmia, unsatisfactory sensation of ejaculation (including painful ejaculation and ejaculatory anhedonia), and absent ejaculate (including retrograde ejaculation and aspermia). We also cover several special scenarios including hematospermia, spinal cord injury and fertility with anejaculation. In this paper, we will review the anatomy and pathophysiology of normal ejaculation to establish the baseline knowledge of how this pathway can go awry. We will then briefly review the critical diagnostic criteria, pertinent steps in evaluation, risk factors, and causes (if known) for each of the ejaculatory disorders. Finally, the bulk of the paper will discuss current management strategies of each disorder.

Sexual dysfunction and male infertility

Infertility affects up to 12% of all men, and sexual dysfunction occurs frequently in men of reproductive age, causing infertility in some instances. In infertile men, hypoactive sexual desire and lack of sexual satisfaction are the most prevalent types of sexual dysfunction, ranging from 8.9% to 68.7%. Erectile dysfunction and/or premature ejaculation, evaluated with validated tools, have a prevalence of one in six infertile men, and orgasmic dysfunction has a prevalence of one in ten infertile men. In addition, infertile men can experience a heavy psychological burden. Infertility and its associated psychological concerns can underlie sexual dysfunction. Furthermore, general health perturbations can lead to male infertility and/or sexual dysfunction. Erectile dysfunction and male infertility are considered proxies for general health, the former underlying cardiovascular disorders and the latter cancerous and noncancerous conditions. The concept that erectile dysfunction in infertile men might be an early marker of poor general health is emerging. Finally, medications used for general health problems can cause sperm abnormalities and sexual dysfunction. The treatment of some causes of male infertility might improve semen quality and reverse infertility-related sexual dysfunction. In infertile men, an investigation of sexual, general, and psychological health status is advisable to improve reproductive problems and general health.

Delayed Ejaculation: Pathophysiology, Diagnosis, and Treatment

Delayed ejaculation (DE) is a poorly defined and uncommon form of male sexual dysfunction, characterized by a marked delay in ejaculation or an inability to achieve ejaculation. It is often quite concerning to patients and their partners, and sometimes frustrates couples' attempts to conceive. This article aims to review the pathophysiology of DE and anejaculation (AE), to explore our current understanding of the diagnosis, and to present the treatment options for this condition. Electronic databases were searched from 1966 to October 2017, including PubMed (MEDLINE) and Embase. We combined “delayed ejaculation,” “retarded ejaculation,” “inhibited ejaculation,” or “anejaculation” as Medical Subject Headings (MeSH) terms or keywords with “epidemiology,” “etiology,” “pathophysiology,” “clinical assessment,” “diagnosis,” or “treatment.” Relevant sexual medicine textbooks were searched as well. The literature suggests that the pathophysiology of DE/AE is multifactorial, including both organic and psychosocial factors. Despite the many publications on this condition, the exact pathogenesis is not yet known. There is currently no single gold standard for diagnosing DE/AE, as operationalized criteria do not exist. The history is the key to the diagnosis. Treatment should be cause-specific. There are many approaches to treatment planning, including various psychological interventions, pharmacotherapy, and specific treatments for infertile men. An approved form of drug therapy does not exist. A number of approaches can be employed for infertile men, including the collection of nocturnal emissions, prostatic massage, prostatic urethra catheterization, penile vibratory stimulation, probe electroejaculation, sperm retrieval by aspiration from either the vas deferens or the epididymis, and testicular sperm extraction.