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PubMedDate not supplied

Magnesium in human semen: possible role in premature ejaculation.

Although magnesium is involved in many biological process and it is found higher levels in semen than serum, its role in human semen has not been elucidated. This investigation was conducted to evaluate the relationship between premature ejaculation and the levels of seminal magnesium. The levels of magnesium, zinc, copper, and selenium were evaluated with an atomic absorption spectrophotometer in serum and seminal plasma in 3 groups of men: (a) normal sperm parameters (15) (b) oligoasthenozoospermia (15), and genuine premature ejaculation (9). There were normal serum and semen levels of all the elements in the three groups, but significantly lower seminal plasma magnesium levels in men with premature ejaculation. The hormonal profile, body mass index (BMI) had no association with premature ejaculation. Decreased levels of magnesium gives rise to vasoconstriction from increased thromboxane level, increased endothelial intracellular Ca2+, and decreased nitric oxide. This may lead to premature emission and ejaculation processes. Magnesium is probably involved in semen transport. More research into the role of magnesium in the male physiology of reproductive tract, especially its association with premature ejaculation, is advocated.

Adult↗
PubMed2003

Different fertilization rates between immotile testicular spermatozoa and immotile ejaculated spermatozoa for ICSI in men with Kartagener's syndrome: case reports.

We report two cases of infertility treatment in couples where males suffered from Kartagener's syndrome (KS) and a total absence of motile sperm in the ejaculate. A total of three ICSI cycles was carried out. In all cycles, viable ejaculated or testicular spermatozoa were selected using the hypo-osmotic swelling (HOS) test. Case 1: In the first ICSI cycle total fertilization failure occurred after using ejaculated spermatozoa. In the following cycle testicular spermatozoa were used for ICSI, resulting in 75% fertilized oocytes and a pregnancy. Case 2: In the same ICSI cycle 50% of the oocytes were injected with ejaculated and 50% with testicular spermatozoa. The fertilization rates were 44 and 56% respectively and high quality embryos were achieved in both groups. One single embryo derived from testicular sperm was transferred with a resulting singleton pregnancy. In conclusion, testicular sperm for ICSI seem to have reliable fertilization capacity in men with KS, while ejaculated sperm, even if tested viable, seem more unpredictable. HOS test for selection of viable sperm for ICSI is recommended when ejaculated as well as testicular sperm are used for ICSI.

Adult↗
PubMed1986

ATP-induced reactivation of ram testicular, cauda epididymal, and ejaculated spermatozoa extracted with Triton X-100.

It was possible to demembrante and reactivate not only freshly collected testicular, cauda epididymal, and ejaculated ram sperm but also sperm that had been stored for several days at 0 degrees C and for several months at -196 degrees C in rete testis fluid or egg yolk citrate media. Sperm were usually washed free of seminal plasma before demembranation, but this was not essential for reactivation. Bovine serum albumin (1.0%) in the wash medium increased the survival of sperm, but more than 0.25% in the extraction medium decreased reactivation. A macro-molecular component of cauda epididymal fluid also inhibited the reactivation of testicular sperm. Triton X-100 concentrations between 0.01% and 1.00% in the extraction medium were satisfactory for demembranating the sperm. Rapid cooling (i.e., cold shock) mimicked the effect of detergent in making the sperm responsive to added ATP and demonstrated that damage to ram sperm in cold shock does not involve the axoneme. Ejaculated and cauda sperm were reactivated immediately on addition of ATP and activity persisted for up to 10 min. Testicular sperm, on the other hand, required about 4 min to become fully reactivated. The optimal ATP concentration for activation of sperm was 0.1-1.0 mM. Magnesium ions (0.1-1.0 mM) were important for reactivation, and testicular sperm required a higher magnesium concentration than did cauda or ejaculated sperm. Manganese ions were almost as effective as magnesium for reactivating cauda epididymal and ejaculated sperm. Cobalt and cadmium ions were much less active for cauda and ejaculated sperm and none of these ions were effective for testicular sperm. Fluoride (25-50 mM) inhibited reactivation. The presence of 50 microM cAMP in the extraction medium or preincubation of testicular sperm with theophylline or caffeine increased low levels of activation, but this was not evident with ejaculated or cauda sperm. We conclude that the motor apparatus is already functionally assembled in spermatozoa on leaving the testis, but some fine adjustment must take place during maturation in the epididymis.

Adenosine Triphosphate↗
PubMed2002

Nature of DNA damage in ejaculated human spermatozoa and the possible involvement of apoptosis.

Numerous studies have shown the presence of DNA strand breaks in human ejaculated spermatozoa. The nature of this nuclear anomaly and its relationship to patient etiology is however poorly understood. The aim of this study was to investigate the relationship between nuclear DNA damage, assessed using the TUNEL assay and a number of key apoptotic markers, including Fas, Bcl-x, and p53, in ejaculated human spermatozoa from men with normal and abnormal semen parameters. We also determined the nature of the DNA damage by examining the percentage of ejaculated spermatozoa exhibiting DNA damage using the comet assay and by challenging sperm chromatin to attack by micrococcal nuclease S7 and DNase I. We show that TUNEL positivity and apoptotic markers do not always exist in unison; however, semen samples that had a low sperm concentration and poor morphology were more likely to show high levels of TUNEL positivity and Fas and p53 expression. In addition, the DNA damage in ejaculated human sperm is represented by both single- and double-stranded DNA breaks, and access to the DNA is restricted by the compacted nature of ejaculated spermatozoa. This DNA protection is poorer in men with abnormal semen parameters. We propose that the presence of DNA damage is not directly linked to an apoptotic process occurring in spermatozoa and arises due to problems in the nuclear remodeling process. Subsequently, the presence of apoptotic proteins in ejaculated spermatozoa may be linked to defects in cytoplasmic remodeling during the later stages of spermatogenesis.

Apoptosis↗
PubMedDate not supplied

Comparison of sperm quantity and quality in antegrade V retrograde ejaculates obtained by vibratory penile stimulation in males with spinal cord injury.

Reduced fertility in men with spinal cord injury results from the inability to ejaculate and poor semen quality. Vibratory penile stimulation can induce ejaculation in many men with spinal cord injuries, but few studies have reported the effects of repeated vibratory stimulation on quantitative semen analysis tests. Fourteen spinal cord-injured males were enrolled in a prospective study to develop a quantitative profile of antegrade and retrograde ejaculate specimens collected during repeated vibratory stimulation. Antegrade specimens were obtained in 51 (84%) and retrograde specimens were obtained in all of the 61 trials (100%). Sperm were present in 70% and 64% of the antegrade and retrograde samples, respectively. Of the patients who underwent repeated vibratory stimulation attempts, three showed marked improvement in sperm counts and characteristics with repeated vibration and five showed normal fluctuation or no change in semen quality. Overall, there was a trend toward higher sperm counts in the antegrade samples (mean, 74.1 million) than in the retrograde samples (mean, 40 million), but no statistical significance was found. Mean sperm motility, sperm progressive motility, and percent normal sperm morphology were not significantly different between antegrade and retrograde specimens. Fructose and zinc, semen markers that reflect the presence of a true ejaculate, were present in all antegrade and retrograde specimens. In conclusion, (1) both antegrade and retrograde ejaculation occur with vibratory penile stimulation, with antegrade samples containing greater numbers of sperm but retrograde samples also having significant sperm counts, (2) repeated vibration may increase sperm concentration or may result in only minimal changes reflective of normal fluctuations, and (3) vibratory stimulation results in true ejaculation, as evidenced by semen markers.

Adult↗
PubMed2000

Sperm motility from the vas deferens of spinal cord injured men is higher than from the ejaculate.

PURPOSE: Recent evidence suggests that the seminal plasma of spinal cord injured men contributes to their distinctive semen profile of normal sperm concentration but low sperm motility and viability. This finding indicates that sperm in these men may be normal before exposure to the seminal and prostatic fluids. To investigate this question we compared vas aspirated to ejaculated sperm in 12 men with spinal cord injury and 14 healthy, age matched controls. MATERIALS AND METHODS: Ejaculate was collected by penile vibratory stimulation or electroejaculation in spinal cord injured men and by masturbation in controls. Sperm was aspirated via microsurgery from 1 hemisectioned vas deferens in spinal cord injured men and during routine elective vasectomy in controls. Ejaculated and aspirated specimens were compared. RESULTS: In men with spinal cord injury mean vas aspirated sperm motility and viability plus or minus standard error of mean were significantly higher than mean ejaculated sperm motility and viability (54.4% +/- 5.0% and 74.1% +/- 5.3% versus 14.1% +/- 2.6% and 26.1% +/- 4.9%, respectively). In controls mean vas aspirated sperm motility and viability were not significantly different from mean ejaculated sperm motility and viability (77.5% +/- 5.2% and 88.9% +/- 2.5% versus 74.3% +/- 5.2% and 85.0% +/- 3.5%, respectively). CONCLUSIONS: In spinal cord injured men sperm motility and viability were significantly higher before contact with seminal fluids. Although aspirated sperm from men with spinal cord injury generally had lower motility and viability than that of controls, implying that epididymal or testicular factors may also have a part, the greatest decrease was observed in the ejaculate. Further study of infertility in these men should focus on prostatic and seminal vesicle factors.

Adult↗
PubMed2001

Sphincteric events during penile vibratory ejaculation and electroejaculation in men with spinal cord injuries.

PURPOSE: We investigate internal and external sphincter responses during penile vibratory stimulation and electroejaculation in men with spinal cord injury. MATERIALS AND METHODS: Ejaculation induction with simultaneous recording of external and internal sphincter pressures was performed in 9 spinal cord injured men. Of the patients with upper motor neuron lesions 3 underwent penile vibratory stimulation and 3 underwent electroejaculation. In 3 men who did not respond to PVS, including 1 with upper motor neuron and 2 with lower motor neuron lesions, penile vibratory stimulation and subsequent electroejaculation were performed. RESULTS: In successful penile vibratory stimulation and electroejaculation upper motor neuron cases external sphincter pressure first reached a peak (average 180 cm. H2O) and subsequently decrease followed in 3 to 10 seconds by a peak in internal sphincter pressure (average 178 cm. H2O), which exceeded external sphincter pressure and ejaculation occurred. During electroejaculation, the pattern progressed, despite complete discontinuation of electrical stimulation. In electroejaculation, there was a trend for a more rapid return of external sphincter pressure greater than internal sphincter pressure, which may explain the electroejaculation retrograde fraction. In nonresponders external sphincter pressure never increased to more than 105 cm. H2O in response to penile vibratory stimulation and no ejaculation was induced. In nonresponders to penile vibratory stimulation, electroejaculation induced a typical sustained increase in internal sphincter pressure and external sphincter pressure but at lower peak pressures. CONCLUSIONS: Forceful contraction of the external sphincter followed by contraction of the internal sphincter always precedes ejaculation during electroejaculation and penile vibratory stimulation. Similarities between penile vibratory stimulation and electroejaculation suggest that the latter induces ejaculation via a complex neurological pathway rather than by simple direct end organ stimulation. The sustained nature of the response to electroejaculation suggests that electrical stimulation should be stopped completely during ejaculation to allow more relaxation of the external sphincter, as this may lead to a decrease in the retrograde fraction.

Ejaculation↗
PubMed2005

Sperm competition, mating rate and the evolution of testis and ejaculate sizes: a population model.

There are various ways to estimate ejaculate expenditure. Ejaculate size or sperm number (s) is an absolute number of units of ejaculate. Relative ejaculate expenditure (E) is the expenditure on the ejaculate as the proportion of the total expenditure on all aspects of the mating, including finding and acquiring a female, and so on. Relative testis size or gonadosomatic index (sigma) is testes mass divided by body mass; it is assumed to reflect the product of mating rate (M) and ejaculate mass (s). In a new model, where mating rate, sperm competition and sperm allocation interact, and where the female's inter-clutch interval is assumed to be independent of s or M, we show that sigma is directly proportional to the mean E for a species; across species sigma and E increase monotonically with sperm competition. However, the relation between s and sperm competition across species depends on the range of sperm competition (low risk or high intensity): s increases with sperm competition at low risk levels, but decreases with sperm competition at high intensity levels. This situation arises because s alpha E/M; both E and M increase with sperm competition, but E increases differently with sperm competition in its two ranges.

Animals↗
PubMed1994

Ejaculation in men: a dynamic endorectal ultrasonographical study.

OBJECTIVE: To study the ejaculatory mechanisms in men using a dynamic endorectal ultrasonographical approach. SUBJECTS AND METHODS: Seven recordings were made of a young healthy volunteer during ejaculation, scanning the longitudinal plane from the bladder neck to the bulbous urethra. RESULTS: The study demonstrated the existence of a pre-ejaculatory phase characterized by a notable decrease in echogenicity of the inner prostate gland, due to the contraction of the pre-prostatic sphincter 13-25 s before ejaculation. Several stages were recorded including an ejaculatory stage with an initial prostatic emission phase lasting 2-20 s and a posterior emission phase through the ejaculatory ducts lasting 3-14 s, with a seminal stoppage of 3-8 s, and finally a urethro-vesical reflux of a minimal fraction of the ejaculate over 5-9 s. The bladder neck and inner gland returned to their resting configuration between 10 and 90 s after ejaculation. CONCLUSIONS: Endorectal ultrasonographical imaging during ejaculation, a recently developed diagnostic procedure, may provide a new approach to ejaculation-related problems.

Adolescent↗
PubMed2004

Lifelong premature ejaculation: from authority-based to evidence-based medicine.

Historically, four periods can be distinguished in the approach to and treatment of lifelong premature ejaculation. Although drug treatment has been an option for many decades, psychotherapy prevailed as the first choice of treatment. However, the application of the principles of evidence-based medicine shows that there is little evidence to support the psychological approach and behavioural treatment. In contrast, controlled trials with selective serotonin reuptake inhibitors, clomipramine and anaesthetic ointments have repeatedly shown the efficacy of both daily and 'as-needed' drug treatment to delay ejaculation. Currently, an evidence-based approach is gradually replacing the authority-based psychological attitude that characterized the view of premature ejaculation. Based on psychopharmacological studies there is evidence that premature ejaculation is related to a diminished serotonergic neurotransmission, and 5-HT2C or 5-HT1A receptor disturbances. Moreover, animal studies show the presence of a distinct ejaculation-related neural circuit in the central nervous system; its role in premature ejaculation remains to be elucidated.

Age Factors↗
PubMed2004

Disorders of orgasm and ejaculation in men.

INTRODUCTION: Ejaculatory/orgasmic disorders, common male sexual dysfunctions, include premature ejaculation, inhibited ejaculation, anejaculation, retrograde ejaculation and anorgasmia. AIM: To provide recommendations/guidelines concerning state-of-the-art knowledge for management of ejaculation/orgasmic disorders in men. METHODS: An International Consultation in collaboration with the major urology and sexual medicine associations assembled over 200 multidisciplinary experts from 60 countries into 17 committees. Committee members established specific objectives and scopes for various male and female sexual medicine topics. The recommendations concerning state-of-the-art knowledge in the respective sexual medicine topic represent the opinion of experts from five continents developed in a process over a 2-year period. Concerning the Disorders of Ejaculation/Orgasm in Men Committee, there were nine experts from six countries. MAIN OUTCOME MEASURE: Expert opinion was based on grading of evidence-based medical literature, widespread internal committee discussion, public presentation and debate. RESULTS: Premature ejaculation management is dependent upon etiology. When secondary to ED, etiology-specific treatment is employed. When lifelong, initial pharmacotherapy (SSRI, topical anesthesia, PDE5 inhibitors) is appropriate. When associated with psychogenic/relationship factors, behavioral therapy is indicated. When acquired, pharmacotherapy and/or behavioral therapies are preferred. Retrograde ejaculation, diagnosed with spermatozoa and fructose in centrifuged post-ejaculatory voided urine, is managed by education, patient reassurance, pharmacotherapy or bladder neck reconstruction. Men with anejaculation or anorgasmia have a biologic failure of emission and/or psychogenic inhibited ejaculation. Men with age-related penile hypoanesthesia should be educated, reassured and be instructed in revised sexual techniques which maximize arousal. CONCLUSIONS: More research is needed in understanding management of men with ejaculation/orgasmic dysfunction.

Anesthetics, Local↗
PubMed2005

Thyroid-stimulating hormone assessments in a Dutch cohort of 620 men with lifelong premature ejaculation without erectile dysfunction.

INTRODUCTION: Apart from the involvement of central serotonergic neurotransmission on lifelong premature ejaculation, interference of thyroid function has been speculated. AIM: To study thyroid function in a large group of men with lifelong premature ejaculation (LPE). METHODS: Lifelong premature ejaculation was defined as an intravaginal ejaculation latency time (IELT) of less than 1 minute. Any consecutive man with LPE and no erectile dysfunction assessed by medical history and the International Index of Erectile Function (IIEF-5) was eligible for the study. Apart from the assessment of thyroid-stimulating hormone (TSH) also free thyroxin (f T4) was determined in case of a TSH of <0.3 mU/L or TSH of >4.0 mU/L (being the lower and upper limits of normal values, respectively). Blood samples were drawn throughout the day within office hours. MAIN OUTCOME MEASURES: Thyroid-stimulating hormone and f T4. RESULTS: Included were 620 men; age (mean+/-SD) was 39.9+/-9.4 years (range 19-65). TSH concentrations from morning, early and late afternoon samples did not differ. The geometrical mean TSH concentration was 0.85 mU/L (95% confidence intervals: 0.82-0.90) with a coefficient of variation of 57.9%. Fourteen men had a TSH of <0.3 mU/L (2.2%), while five men (0.8%) of >4.0 mU/L. All men with an abnormal TSH had a normal f T4 (between 10 and 20 pmol/L). No relationship was found between age and TSH concentrations. CONCLUSION: Thyroid-stimulating hormone distribution was analyzed in a cohort of Dutch men with lifelong premature ejaculation and no erectile dysfunction. According to statistical analysis, there appeared to be no interaction between this ejaculatory complaint and the prevalence of thyroidal dysfunction. However, further studies are needed to gain more insight into the role of thyroid dysfunction and regulation of ejaculation time.

Adult↗
PubMed2006

Changing paradigms from a historical DSM-III and DSM-IV view toward an evidence-based definition of premature ejaculation. Part II--proposals for DSM-V and ICD-11.

BACKGROUND: In the Diagnostic and Statistical Manual of Mental Disorders (DSM), a descriptive definition for premature ejaculation (PE) that was based on historical assumptions has been accepted. AIM: To formulate a new functional definition of PE in the DSM. METHODS: A "syndrome" approach instead of a "complaint" approach is applied and evidence-based data from epidemiological and clinical studies are used. RESULTS: A new functional definition of PE should pertain to a cluster of "symptoms" of a distinct "syndrome." A syndrome rather than a descriptive definition should distinguish Lifelong and Acquired PE variants. Evidence-based data also suggest another PE type "Natural Variable PE," which is not a typical syndrome but rather a cluster of inconsistent symptoms of rapid ejaculation. Moreover, in "Natural Variable PE" the occurrence of rapid ejaculation is not based on neurobiological or psychological pathology, but belongs to the normal variability of sexual performance. Its prevalence is probably much higher than that of Lifelong and Acquired PE. We propose three separate operationalized definitions of these three PE types for the pending DSM-V and ICD-11, which include a quantification of the ejaculation time (intravaginal ejaculation latency time), inability of ejaculatory control, and a description of severity of PE in terms of psychological distress. CONCLUSION: The use of the intravaginal ejaculation latency time into the DSM-V and ICD-11 would mean that statistical evidence becomes accepted as one of the mainstays for establishing an evidence-based definition of the three PE types.

Coitus↗
PubMed1976

Effect of frequent ejaculation on semen characteristics in rams.

Sixteen Suffolk rams were ejaculated repeatedly for a period of eight hours during the month of November. Ejaculates were examined for semen characteristics. Volume density and number of sperm per ejaculate declined significantly in successive ejaculates. Motility and percentage abnormal sperm were not affected by frequent collection. It is concluded that the number of sperm per ejaculate, after the eighth ejaculate, could fall below that required for fertilisation to occur, particularly in progestagen treated ewes.

Animals↗
PubMed1989

Influence of ejaculation frequency on semen characteristics in chimpanzees (Pan troglodytes).

Semen samples were obtained by masturbation from 6 chimpanzees and the spontaneously liquefied fraction and the remaining coagulum were studied separately. When semen was collected once or twice a week, large intra-individual variations were observed for all measures. The liquefied fraction represented 26.5 +/- 3.2% (weighted mean +/- s.d.) of the total ejaculate but contained 51.3 +/- 3.8% of all emitted spermatozoa. Fructose concentration was higher in the coagulum than in the liquefied fraction (29.3 +/- 3.0 mumol/ml vs 12.0 +/- 2.7 mumol/ml, P less than 0.001) whereas acid phosphatase was less concentrated in the coagulum than in the liquefied fraction (3.5 +/- 0.3 x 10(3) IU/ml vs 13.0 +/- 0.9 x 10(3) IU/ml, P less than 0.001). L-Carnitine and citrate concentrations did not differ between the two fractions of the ejaculate. When semen collection was repeated every hour for 5 h, the ejaculate volume increased from 2.6 +/- 0.7 to 4.7 +/- 0.6 ml (P less than 0.001), whereas total sperm count decreased from 1278 +/- 872 x 10(6) to 587 +/- 329 x 10(6) (P less than 0.05) between the 1st and the 6th ejaculate. In the spontaneously liquefied fraction, the sperm count decreased from 984 to 369 x 10(6). The 6 successive ejaculates gave a total of 20.2 +/- 7.6 ml and 4278 +/- 2884 x 10(6) spermatozoa. The increase of the ejaculate volume was essentially due to an increase of the volume of the coagulum which closely correlated with total amount of fructose (from seminal vesicles) (r = 0.913, P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2005

Erection- and ejaculation-preserving cystectomy with orthotopic urinary diversion: is it feasible?

Nerve-sparing techniques to preserve sexual function in men undergoing cystoprostatectomy have been documented by different centers. We evaluated the results of the first 4 erection- and ejaculation-preserving cystectomies performed in our department. The ages of patients ranged between 36 and 43 years. In all cases, patients wished to maintain sexual function. Of the cases, 3 patients had pT1 G3 transitional cell carcinoma (TCC) refractory to treatment and one had pT2a adenocarcinoma of the bladder. Extirpation of the bladder and anterior proximal prostate en bloc with preservation of the vasa deferentia, seminal vesicles, posterior prostate, and neurovascular bundles was performed after pelvic lymphadenectomy. W-ileal neobladder was performed by using 40 cm of ileum. All patients had erections at the third month. Of the cases, 2 patients had antegrade ejaculation. The ejaculate volumes were 0.8 and 1.2 mL in patients with antegrade ejaculation. Patients in the other cases had retrograde ejaculation. All patients were continent day and night. We started clean intermittent catheterization in 1 case because of residual urine. There were no local recurrences. One patient with TCC died because of systemic disease in the postoperative 32nd month. The most important drawback of potent cases in cystectomy decision is erectile dysfunction after radical cystectomy. This drawback causes delay of the operation and sometimes mortality. As was the case in other reports, our limited number of cases in this study demonstrated that erection and ejaculation could be preserved in selected groups of patients.

Adult↗
PubMed2006

Role of peripheral innervation in p-chloroamphetamine-induced ejaculation in anesthetized rats.

The occurrence of ejaculation, which consists of 2 distinct phases (emission and expulsion), requires a tight coordination of peripheral autonomic and somatic nerves. However, some aspects of the mechanism of ejaculation are not clearly defined. To clarify this issue, we used the p-chloroamphetamine (PCA)-induced ejaculation model in anesthetized rats and investigated the effects of selective peripheral nerves lesions on seminal vesicle and bulbospongiosus (BS) muscle activities as representing physiological markers of emission and expulsion phases, respectively. In intact rats, ejaculation induced with PCA (intraperitoneal 5 mg/kg) correlated with coordinated increases in seminal vesicle pressure (SVP) and BS electromyographic activity. PCA-induced ejaculation was still observed in rats with bilateral lesion of hypogastric nerves (HNx), lumbar paravertebral sympathetic chain (LSCx), or dorsal nerves of the penis (DNPx). Conversely, bilateral section of pelvic nerves (PNx) or L6-S1 dorsal roots (DRx) abolished PCA-induced ejaculation. The amplitude of SVP increases induced by PCA was reduced in PNx, HNx, and LSCx rats, whereas it was unchanged in DRx and DNPx rats. The time interval between SVP increases and BS muscle contractions induced by PCA was comparable in the different neural lesion groups. In conclusion, PCA initiates both emission and expulsion independently from each other. In this model, afferents conveyed by the pelvic nerves appear to be unnecessary for occurrence of BS muscle contractions but are essential for a complete ejaculatory response.

Animals↗
PubMed1984

Minimal requirements for ejaculates used for in vitro fertilization.

Minimal requirements for ejaculates to be used for in vitro fertilization of human oocytes are defined. Experimental results obtained a total concentration of at least 5 X 10(6) spermatozoa per ml are required, with at least 30% of the sperm showing normal motility and normal morphology in the differential spermiocytogram. The total volume of ejaculate should not be less than 1 ml. A total of 140 ejaculates from patients taking part in the in vitro fertilization program were examined. In 60 ejaculates (42.9%) bacteria concentrations of greater than 10(5)/ml were found. Eighty (57.1%) of the probes were negative or had bacteria concentrations less than 10(4)/ml. Mycoplasma was found in 30 of the examined ejaculates (21.4%) and the second most frequent group of microorganisms were enterococci found in 15 patients (10.7%). Anaerobic organisms in concentrations of more than 10(5)/ml were not detected. After insemination of one or more pelviscopically obtained oocytes with sperm of the husband in 14 out of 22 cases (63.6%) with bacteria concentrations greater than 10(5)/ml the cleavage of at least one oocyte occurred leading to an embryo-transfer rate of 63.6%. In 14 of 31 ejaculates with negative bacteriological findings (45.2%) at least one of the inseminated oocytes was fertilized. Direct effect of microorganism contaminated sperm on the human in vitro fertilization system resulting in reduced fertilization rates cannot be demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

Ejaculation↗