Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “EJACULATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources
PubMed2005

Sperm competition and male ejaculate investment in Nauphoeta cinerea: effects of social environment during development.

Selective pressure arising from sperm competition has been predicted to influence evolutionary and behavioural adjustment of ejaculate investment, but also may influence developmental adjustment of ejaculate investment. Immature males able to target resources strategically based on the competitive environment they will experience when they become sexually mature should be at a selective advantage. In our study we investigated how the presence of potential competitors or mates affects ejaculate and testes investment during development in the cockroach Nauphoeta cinerea, a species where males control female remating via their ejaculate size (large spermatophores prevent females from remating and therefore function to avoid sperm competition for males) and females store sperm. Our aim was to determine whether the social environment influences developmental adjustment of ejaculate investment and the relative importance of ejaculate components with different functions; avoidance of or engagement in sperm competition. We conclude that the social environment can influence developmental and behavioural flexibility in specific ejaculate components that may function to avoid or engage in sperm competition.

Analysis of Variance↗
PubMed1999

[Knowledge of the "Gräfenberg zone" and female ejaculation in ancient Indian sexual science. A medical history contribution].

Ancient Indian texts in sexology (kamaśastra) from the 11th century onwards prove that their authors knew about the area later termed the "Gräfenberg zone" in Europe, as well as about the female ejaculation connected with the stimulation of this area. The Gräfenberg zone is a sexually arousable zone in the front part of the vagina, stimulation of which can lead to the discharge of liquid from the urethra, a phenomenon which is described as female ejaculation. The german gynaecologist Ernst Gräfenberg, who worked in America, described this zone, situated beneath the clitoris, for the first time (at least in this century) in Western medicine in an article published in 1950. (There are, however, evidences, that the 17th-century anatomist Regnier de Graaf had knowledge about the mentioned erogenous zone as well as female ejaculation.) Since the 1980s the so-called Gräfenberg zone, popularly termed "G-spot", and female ejaculation have been controversially discussed medically as well as in popular science, first in the United States, then in Europe; both phenomena have meanwhile been accepted as facts in medical manuals and reference books (e.g. the "Pschyrembel"). Whereas the oldest and most well-known sexological-erotological work of Ancient India, the Kamasutra, dating probably from the third century A.D., apparently did not know the Gräfenberg zone and female ejaculation, texts such as the Pañcasayaka (11th century), Jayamangala (Yaśodhara's commentary on the Kamasutra from the 13th century), the Ratirahasya (13th century), as well as the late kamaśastra-works Smaradipika and Anangaranga (16th century?) demonstrably describe both, the Gräfenberg zone and female ejaculation, in great detail. The female ejaculation is described already in the 7th century in a non-kamaśastra-text, in a work of the poet Amaru called the Amaruśataka.

Clitoris↗
PubMed1984

Human sperm penetration in bovine cervical mucus clinical studies. II. Use of split ejaculates.

Sperm penetration through bovine cervical mucus was determined and correlated with the sperm characteristics in three fractions of the split ejaculate and in the whole ejaculate from 40 men of infertile couples in which a female cause of infertility had been ruled out. Sperm concentration and motility were found to be significantly higher in the first fraction (n = 40) as compared with the rest of the fractions and the whole ejaculate, whereas normal sperm morphology was not significantly different among the various fractions and the whole ejaculate. The bovine mucus penetration (BCMP) test was found to be normal in a significantly high percentage (58%) of samples of the first fraction as compared with the other two fractions (32% and 17%, respectively) and the whole ejaculate (35%) (n = 17). Moreover, in the first fraction of the split ejaculate, the results of the BCMP test were correlated significantly with sperm concentration (P less than 0.01), motility (P less than 0.0001), and morphology (P less than 0.02). The data demonstrate the superiority of the first fraction of the split ejaculate in terms of cervical mucus penetrability and sperm characteristics.

Adult↗
PubMed1980

[Fructose in ejaculate--correlation with age of proband (author's transl)].

No significant correlation was found to exist between the age of 95 males and fructose level in one millilitre of each one's ejaculate (correlation coefficient 4 = -0.139) nor between proband age and fructose level by volume of ejaculate (r = -1.141). Yet, fructose levels in ejaculate of men below 30 years of age tended quite often to be higher than those recorded from ejaculate of men above 40. The ejaculates tested were different in quality. Close and statistically important negative correlations between proband age and total fructose in ejaculate (r = -0.620) were recordable only from men with excellent average spermatozoan motility, one hour from ejaculation and not even largely reduced after another five hours.

Adult↗
PubMed2005

Neural control of ejaculation.

Ejaculation is the most reinforcing component of sexual behavior. However, the neural substrates mediating ejaculation and processing ejaculation-related signals remain poorly understood. We review the current understanding of central control of ejaculation. Specifically, the recent identification of a candidate spinothalamic pathway involved in relay of ejaculation-specific signals is discussed. In addition, the discovery of a neural population of lumbar interneurons playing an pivotal role in expression of ejaculation is reviewed.

Animals↗
PubMed2005

Psychological treatment strategies for rapid ejaculation: rationale, practical aspects, and outcome.

The landscape has dramatically changed for patients seeking treatment for rapid ejaculation. Previously, psychotherapy or behavioral treatment was considered to be the treatment of choice for this troubling sexual dysfunction. Since the early 1990s, an efficacious alternative treatment has emerged-the off-label administration of SSRI medications. Currently, several short-acting SSRI compounds are in phase III clinical trials and are likely to receive approval as the first medical treatment for rapid ejaculation. Given the presumed efficacy of these new compounds and the off-label use of the current SSRIs, one might conclude that psychotherapy\behavior therapy for rapid ejaculation is an obsolete and antiquated intervention. On the contrary, psychotherapy is now more relevant than ever. The two aims of this paper are to review psychological/behavioral therapies for rapid ejaculation and to discuss the important role of combined psychological and medical treatment. In the new age of SSRI treatment for rapid ejaculation, some form of psychological/behavioral intervention is essential to help patients/couples make better use of medical therapies, to learn skills to delay ejaculation once off medication, to bolster sexual confidence, and to enhance patient and partner sexual satisfaction.

Ejaculation↗
PubMed2005

Do different portions of the boar ejaculate vary in their ability to sustain cryopreservation?

Previous studies have shown sperm quality post-cryopreservation differs depending on the fraction of the seminal plasma boar spermatozoa are fortuitously contained in. As such, spermatozoa contained in the first 10 mL of the sperm-rich fraction (portion I) have better sustained handling procedures (extension, handling and freezing/thawing) than those contained in the ulterior part of a fractionated ejaculate (second portion of the sperm-rich fraction and the post-spermatic fraction, portion II). However, those studies were performed using pooled samples. In the present study, individual ejaculates were used. Split ejaculates (portions I and II) from five boars were frozen and thawed using a conventional freezing protocol, followed by computer-assisted motility and morphology analysis (CASA and ASMA, respectively), as well as an Annexin-V assay for spermatozoa from each boar and ejaculate portion. Significant differences between portions were observed in all ASMA-derived variables, except in one boar. Also significant differences were observed between boars and ejaculate portions in sperm quality post-thaw. We identified, however, boars showing best results of motility and sperm membrane integrity post-thaw in portion I, while in other boar the best results was observed in portion II. It is concluded that the identification of the ejaculate portion more suitable to sustain cryopreservation in each individual boar may be a readily applicable and easy technique to diminish variation in sperm freezability among boars.

Animals↗
PubMed2004

On-demand treatment of premature ejaculation with clomipramine and paroxetine: a randomized, double-blind fixed-dose study with stopwatch assessment.

OBJECTIVE: To investigate the degree of ejaculation delay induced by on-demand treatment with 20 mg paroxetine and 25 mg clomipramine and to assess the type and severity of non-sexual side-effects of treatment at the day of and the day after treatment with these drugs. METHOD: A randomized, double-blind, fixed-dose, on-demand study in 30 men with lifelong premature ejaculation was performed. During a 1-month baseline period and a 4-week drug treatment period patients assessed the intravaginal ejaculation latency time (IELT) at home with a stopwatch. Only men with an IELT <1 min were randomly assigned to drug treatment. Patients assessed the drug coitus interval time (DCIT) and used the UKU side effect scale questionnaire at baseline, the day of and the day after intercourse. RESULTS: On-demand treatment with 25 mg clomipramine, with a mean DCIT of 5.14 h, led to a 4.05 (95%CI: 3.26-5.02) fold-increase of the IELT. On-demand treatment with 20 mg paroxetine, with a mean DCIT of 5.39 h, led to a 1.41 (95%CI: 1.22-1.63) fold-increase of the IELT. Both drugs had a high incidence of non-sexual side effects at the coitus day and the next day. At the day of coitus paroxetine led to significant sleepiness and yawning compared to clomipramine. At the day after coitus clomipramine induced significant nausea compared to paroxetine. CONCLUSION: On-demand treatment with 25 mg clomipramine led to a clinical relevant ejaculation delay. In contrast, 20 mg paroxetine had no clinical relevant ejaculation delay in men with lifelong premature ejaculation with an IELT of less than 1 minute. Both drugs exert mostly mild yet annoying non-sexual side effects both at the coitus day and the next day.

Adolescent↗
PubMed1998

Efficacy and safety of fluoxetine, sertraline and clomipramine in patients with premature ejaculation: a double-blind, placebo controlled study.

PURPOSE: We compared the efficacy and safety of fluoxetine, sertraline, clomipramine and placebo for the oral pharmacotherapy of premature ejaculation. MATERIALS AND METHODS: The study included 36 men (mean age 44 years) who had intravaginal ejaculation latency of less than 2 minutes. Patients took each of 3 drugs and the placebo consecutively during a 4-week period per each agent. Efficacy and side effects data were obtained by a self-reported patient questionnaire that rated intravaginal ejaculation latency, sexual satisfaction of patient and partner, and possible side effects. RESULTS: After 4 weeks of treatment with placebo, fluoxetine, sertraline and clomipramine the mean intravaginal ejaculation latency time was significantly increased from 46 seconds to 2.27 minutes, 2.30 minutes, 4.27 minutes and 5.75 minutes, respectively (all p <0.01). However, treatment with clomipramine or sertraline caused a greater increase in mean intravaginal ejaculation latency time than fluoxetine or placebo (p <0.01). Patient sexual satisfaction rate after treatment with clomipramine was significantly higher (p <0.05) than with sertraline, fluoxetine or placebo. Partner sexual satisfaction rate was also higher with clomipramine than with sertraline or fluoxetine but no statistical difference was found. The incidence of side effects with clomipramine was significantly higher (p <0.05) compared to that of fluoxetine, sertraline and placebo, while no significant difference among sertraline, fluoxetine and placebo was noted. CONCLUSIONS: In men with premature ejaculation clomipramine was the most useful drug in terms of efficacy. Treatment with sertraline was nearly as effective and had a lower incidence of side effects.

1-Naphthylamine↗
PubMed2002

The neurobiological approach to premature ejaculation.

PURPOSE: Data showing the neurobiological background of rapid ejaculation was reviewed. In addition, new hypotheses to integrate clinical symptomatology, psychopharmacotherapy and psychotherapy of rapid ejaculation with brain function are provided. MATERIALS AND METHODS: A computerized MEDLINE search, and manual bibliographic review of cross-references and neurobiological animal studies were performed. These reports were analyzed, summarized and compared with the studies performed by the author. RESULTS: The literature on premature ejaculation published between 1887 and 2001 was reviewed. It appeared that the various psychological hypotheses and psychotherapies have not adequately been investigated. In contrast, psychopharmacological treatment studies, animal research data and stopwatch assessments in men with rapid (premature) ejaculation indicate that lifelong rapid ejaculation is a neurobiological phenomenon related to central serotonergic neurotransmission and likely influenced by hereditary factors. CONCLUSIONS: Basic and clinical psychopharmacological studies suggest that premature ejaculation is a not a psychological disturbance but a neurobiological phenomenon.

Animals↗
PubMed1993

Penetration of ciprofloxacin into prostatic fluid, ejaculate and seminal fluid in volunteers after an oral dose of 750 mg.

To evaluate an effective dose for the treatment of bacterial prostatitis the concentrations of ciprofloxacin were measured in prostatic fluid, ejaculate and the cell-free seminal fluid of 15 healthy volunteers who received an oral dose of 750 mg. ciprofloxacin while in a fasting state. Venous blood samples were taken in all subjects at 1, 2, 3 and 4 hours. In 6 subjects blood samples were also taken after 8 and 12 hours. Urine was collected in all subjects during 0 to 4 hours and in the 6 subjects also during 4 to 8 hours and 8 to 12 hours. Prostatic fluid could be obtained in 10 subjects by prostatic massage 4 hours after drug intake. So as not to contaminate the urethra with ciprofloxacin the subjects were not allowed to void until 4 hours after drug intake. Iopamidol (3.162 gm.), a renal contrast agent, was administered intravenously concomitantly with oral ciprofloxacin intake. After 8 hours iohexol (3.235 gm.) was administered intravenously. These agents were measured in prostatic fluid, ejaculate and seminal fluid to assess the contamination of those fluids by urine. All drug measurements were done by high pressure liquid chromatography. The median plasma concentrations of ciprofloxacin were 2.1 mg./l. at 1 hour (maximum concentration), 0.9 mg./l. at 4 hours and 0.2 mg./l. at 12 hours. The median concentration in prostatic fluid was 0.23 mg./l. with a fluid-to-plasma concentration ratio of 0.23. The median concentration in the ejaculate (seminal fluid) after 4 hours was 7.4 mg./l. (6.6 mg./l.) and after 12 hours it was 2.0 mg./l. (1.9 mg./l.) with corresponding ejaculate (seminal fluid)-to-plasma concentration ratios of 8.4 (7.7) and 8.0 (6.6), respectively. Thus, ciprofloxacin is concentrated several-fold in ejaculate and seminal fluid but not in prostatic fluid. According to the results the concentrations of ciprofloxacin in prostatic fluid exceed the minimal inhibitory concentration-90% for Enterobacteriaceae but not for Pseudomonas, enterococci and staphylococci, whereas the concentrations in ejaculate and seminal fluid are sufficiently elevated to include the total spectrum of sensitive strains causing bacterial prostatis.

Administration, Oral↗
PubMed1999

Short-term analysis of the effects of as needed use of sertraline at 5 PM for the treatment of premature ejaculation.

OBJECTIVES: Pharmacotherapy using selective serotonin reuptake inhibitors (SSRIs) for men with primary premature ejaculation is promising. In particular, the strategy of taking a pill "as needed" may offer an attractive option. To investigate the possibility of self-therapy for the treatment of premature ejaculation, we compared the efficacy of sertraline taken as needed with that of continuous medication. METHODS: Since 1996, we have treated 24 men with sertraline on an as needed basis for primary premature ejaculation. Sertraline was chosen from among the SSRIs because a large dose need not be divided and because peak plasma levels occur 4 to 8 hours after oral administration, making 5 PM a suitable time for administration (by which time a man may know whether sexual intercourse is likely to occur later that evening). Each patient was started on 50 mg daily for 2 weeks, and the dose was then adjusted to 50 or 100 mg on the day of intercourse only (PRN). RESULTS: After 6 weeks, 18 men were still taking medication, and 6 had dropped out. Among the 18, the mean ejaculation latency was 23 +/- 19 seconds before treatment, 5.9 +/- 4.2 minutes after 2 weeks of 50 mg daily, 5.1 +/- 3.8 minutes after 2 weeks of 50 or 100 mg PRN, and 4.5 +/- 2.7 minutes after 4 weeks of 50 or 100 mg PRN. Mean sexual satisfaction scores (5, extremely satisfied; 0, extremely unsatisfied) for men were 0.8 +/- 0.8 before treatment, 3.8 +/- 1.2 after 2 weeks of 50 mg daily, 3.4 +/- 1.0 after 2 weeks of 50 or 100 mg PRN, and 3.2 +/- 0.7 after 4 weeks of 50 or 100 mg PRN. For their partners, mean sexual satisfaction scores were 1.1 +/- 0.7 before treatment, 3.2 +/- 1.6 after 2 weeks of 50 mg daily, 3.1 +/- 1.4 after 2 weeks of 50 or 100 mg PRN, and 3.3 +/- 1.2 after 4 weeks of 50 or 100 mg PRN. Side effects were intermittent excessive delay of ejaculation in 1 patient, fatigue in 2, and numbness in 1. CONCLUSIONS: If our results are supported by additional long-term clinical studies, self-therapy with sertraline taken PRN at 5 PM for the treatment of premature ejaculation could be as attractive as self-injection therapy for the treatment of erectile dysfunction.

Adult↗
PubMed2000

Multiple ejaculations and chronic fluoxetine: effects on male rat copulatory behavior.

Male rats were treated with fluoxetine (FLX) or vehicle daily for 14 days and copulatory behavior tested on day 15. Rats were either mated to three ejaculations or to sexual exhaustion. Both standard measures and the mount bout analysis were used to evaluate the effects of the chronic FLX on male rat copulatory behavior. Only 56.25% of the animals treated with FLX achieved three ejaculations. FLX inhibited the consumatory aspect of male sexual behavior, especially the ability to achieve three ejaculations, but there was no effect on the propensity of the male to pursue the female. These differences were observed for the first three ejaculations. Analysis of the last three ejaculations in those animals that mated to exhaustion did not reveal an effect of FLX. The behavioral pattern of FLX-treated animals during the first three ejaculations resembled that observed during the last three ejaculatory series in the vehicle-treated animals that mated to exhaustion. The results are discussed in terms of the serotonergic effects on male rat sexual behavior.

Animals↗
PubMed1998

In vitro fertilization treatment for severe male factor: a comparative study of intracytoplasmic sperm injection with testicular sperm extraction and with spermatozoa from ejaculate.

PURPOSE: Our purpose was to evaluate whether the source of spermatozoa influences the results of intracytoplasmic sperm injection (ICSI) treatment in couples with severe male-factor infertility. METHODS: A retrospective analysis of 40 cases of ICSI with testicular-retrieved spermatozoa, matched with 40 cases of ICSI with ejaculated spermatozoa, was performed. We included only couples with normoovulatory females younger than 37 years who were matched according to the day of ovum pickup with the patients in the study group. RESULTS: Eighty cycles were analyzed: 40 cycles using testicular spermatozoa and 40 cycles using ejaculated spermatozoa. In 32 (80%) of the 40 ICSI transcutaneous needle aspiration cycles, we obtained enough spermatozoa to inject all the mature oocytes retrieved. In eight (20%) cases there were not enough spermatozoa to inject all the oocytes. Only 76 (54%) of 141 available oocytes were injected in these eight patients. The oocyte fertilization rates were 42% for the study group and 55.5% for the controls (P < 0.005). Thirty-six (90%) patients in the group with nonobstructive a zoospermia (NOA) and 37 (92.5%) patients in the oligoteratoasthenospermia (OTA) group had embryos for replacement. The mean cleavage rates per cycle (96% with testicular and 93% with ejaculated spermatozoa), the mean number of embryos per transfer (3.72 +/- 1.6 in the NOA group and 4.24 +/- 1.5 in the OTA group), the embryo quality (cumulative embryo scoring = 34.03 +/- 22.62 in the testicular sperm group and 36.08 +/- 19.28 in the ejaculated sperm group), and the clinical pregnancy rates (22.5% in the NOA patients and 20% in the ejaculate group) were not significantly different between groups. CONCLUSIONS: High fertilization, cleavage, and pregnancy rates can be achieved with intracytoplasmic testicular sperm injection from patients with NOA, reaching levels comparable with those of ICSI using ejaculated spermatozoa.

Adult↗
PubMed1990

Reinforcing properties of ejaculation in the male rat: role of opioids and dopamine.

Ejaculation-induced reward in the male rat was evaluated by the conditioned place-preference paradigm. It was supposed that ejaculation induces a reward state such that it can be conditioned to environmental stimuli. Males were allowed to ejaculate once and were then immediately transferred to a place-preference cage. One ejaculation produced place preference. Naloxone (16 mg/kg) not only blocked this place preference but also induced a place aversion. Naloxone by itself had no effect on place preference. It is suggested that release of endogenous opioids renders ejaculation rewarding. Pimozide, in a dose of 1 mg/kg, had no effect on ejaculation-induced reward. Dopamine thus seems to be of slight importance for that effect of copulation. Perhaps compulsive sexual activity obeys the same mechanisms as compulsive drug use in opiate addicts.

Animals↗
PubMed1994

Ejaculation induced by penile vibratory stimulation in men with spinal cord injuries. The importance of the vibratory amplitude.

A total of 66 men with a spinal cord injury (SCI) and ejaculatory dysfunction were included in two different but comparable study populations I (n = 25) and II (n = 41). The level of lesion ranged from C2 to L1 (44 complete). Penile vibratory stimulation (PVS) to induce ejaculation was performed with two different types of vibrators in population I and considerably different ejaculation rates (antegrade+retrograde) occurred depending on the vibrator used. Our experience suggested discrepancies between the manufacturers' specifications and the actual vibrator outputs concerning frequencies and peak-to-peak amplitudes. Retrospectively performed determinations revealed that the manufacturers' specifications regarding the frequencies were accurate whereas the peak-to-peak amplitudes were inaccurate. With a frequency of 100 Hz and determined peak-to-peak amplitudes of 1 mm and 2.5 mm, ejaculation rates of 32% and 96%, respectively, were obtained in population I. This indicates that an adequate peak-to-peak amplitude is essential to exceed an 'ejaculatory threshold' in the majority of SCI men. Furthermore, an ejaculation rate of 83% obtained in a subsequent prospective study of 41 SCI men (population II) verified that a frequency of 100 Hz and a peak-to-peak amplitude of 2.5 mm seems to approach the ideal vibrator output. The ejaculation responses obtained by JS (first author) were reproduced when the PVS was performed by the patient or his partner, indicating that the vibrator output is more important than PVS experience. No major adverse reactions due to autonomic dysreflexia were observed. The lowest level of SCI where antegrade or retrograde ejaculation occurred was T9 and L1, respectively. No absolute predictors for ejaculatory success or failure in relation to patient age, years since lesion, completeness of SCI, urinary bladder management method, hip flexion and bulbocavernous reflexes were observed. Therefore, most SCI men with ejaculatory dysfunction should be considered candidates for PVS.

Adult↗
PubMed1999

Imipramine for successful treatment of retrograde ejaculation caused by retroperitoneal surgery.

Retrograde ejaculation is a known complication following retroperitoneal lymph node dissection. Without further therapy, achieving paternity may be impossible. We evaluated the use of the tricyclic antidepressant imipramine in a new ovarian cycle-dependent dose regime for reversal of retrograde ejaculation in 11 patients desiring fertility. Ten patients with retroperitoneal lymph node dissection performed because of testicular cancer, and one with aortic surgery (thromboendarterectomy) were treated in an open, uncontrolled study with imipramine given at a daily oral dose increasing from 25 to 50 mg for 7 days prior to the planned ejaculation or the expected ovulation of the female partner. In all 11 patients, antegrade ejaculation could be induced (sperm counts: 3.9-276.0 x 10(6)/mL). Major side-effects were not observed, but half of the patients complained of minor degrees of dizziness, weakness, nausea or sweating during medication. Under treatment, two patients with normal sperm concentrations induced a spontaneous pregnancy. One ICSI cycle each was performed in 2 patients, with successful fertilization, out no pregnancy. In conclusion, temporary oral intake of imipramine is an effective and safe treatment to re-establish antegrade ejaculation in patients with retrograde ejaculation following retroperitoneal surgery, thus providing possibilities for paternity either through intercourse or by assisted fertilization.

Adult↗
PubMed1996

Paroxetine in the treatment of premature ejaculation.

OBJECTIVE: To test the efficacy and the adverse effects of a new anti-depressant drug (paroxetine) in the treatment of premature ejaculation. PATIENTS AND METHODS: The study comprised 32 men (mean age 28 years) with premature ejaculation (14 of whom ejaculated before penetration) who were treated with paroxetine (20 mg orally each evening for 2 months). The study group excluded those with neurological and psychiatric disorders, urinary tract infections and drug or alcohol abuse. RESULTS: After about 14 days, the patients' symptoms improved and all patients reported a longer interval before ejaculation. The adverse effects were sleepiness in 19 patients (61%) and mild sensory confusion in 21 (68%), but only one had to withdraw from therapy. Three weeks after the end of therapy, the premature ejaculation recurred in 28 (90%) of the patients. CONCLUSIONS: These results indicate that paroxetine is an effective therapy for premature ejaculation. Further studies with different dosages are necessary to decrease the adverse effects and to prolong the efficacy.

Adult↗