Sperm pathology: a step beyond descriptive morphology. Origin, characterization and fertility potential of abnormal sperm phenotypes in infertile men

Sperm pathology is presented as the discipline of characterizing structural and functional deficiencies in abnormal spermatozoa. This concept complements that of sperm morphology mainly concerned with the appearance of spermatozoa. These two notions collaborate in providing correlations of prognostic value with sperm fertilizing capacity, explaining the mechanisms of sperm inefficiency, suggesting strategies to improve fertilization and opening a door to molecular genetic studies. Phenotypes of genetic origin involving sperm heads, flagella and the neck region are presented describing their clinical manifestations, sperm structure, cytochemistry and genetic background. When available, animal models are used to highlight possible genetic mechanisms. Sperm pathologies secondary to andrological conditions or environmental factors are described, stressing the non-specific nature of the sperm response to noxious agents. The available literature on the prognostic value of sperm pathologies in ICSI is also reviewed. Flagellar anomalies bear a good prognosis, but those affecting the acrosome, sperm chromatin and the neck region entail an increasing chance of failure, which highlights the differential roles played by specific sperm components in fertilization, implantation and early embryonic development. A final discussion is devoted to genetic counselling and the risks involved in using immotile or abnormal spermatozoa in assisted reproduction.     

Effectiveness of divergent selection for open-field activity in rabbits and correlated response for body weight and fertility

Two lines deriving from the same rabbit stock were selected for 8 generations for high (H) or low (L) locomotor activity score in the open field (OFS). The divergent selection was most effective up to the 3rd generation in the H line and up to the 4th generation in the L line. In further generations a decrease of OFS in the H line and a floor effect (OFS = 0) in the L line were observed. The mean OFS increased significantly in consecutive trials in the H line, whereas this increase was non-significant in the L line. There was a negative and very high correlation between the latency to enter the open field and the OFS (–0.95 and –0.98 for the H and L line, respectively). The realized heritability of the OFS was 0.46 and 0.23 in generations 0–3 within the L and H line, respectively, and 0.44 and –0.06 in generations 0–8. As calculated on the basis of divergent selection, the heritability was 0.31 and 0.15 for generations 0–3 and 0–8, respectively. The L rabbits were heavier shortly before (4th wk, P < 0.001) and after (8th wk, P < 0.01) weaning, than those of the H line, whereas the H rabbits grew faster (P < 0.05) between the 4th and 20th wk of age. There was a tendency for decreasing weight gains in consecutive generations. Generally, a lower percentage of H females delivered litters than those of the L line, but this was due to a very low percentage of such females in the 3rd and 6th generations. It can be assumed that H and L lines represent different, i.e., active and passive, coping strategies. These lines of rabbits offer increased possibilities for physiologically and ethologically oriented studies, e.g., on the welfare of caged animals.     

Do cycle disturbances explain the age-related decline of female fertility? Cycle characteristics of women aged over 40 years compared with a reference population of young women

BACKGROUND: The cause of declining fertility with age, in women who still have regular menstrual cycles, is not clear. METHODS: Follicle development, endometrial growth and hormonal patterns were evaluated in cycles of older women (aged 41-46 years; n = 26) who previously were normally fertile, and these cycles were compared with a reference group of relatively young fertile women (aged 22-34 years; n = 35). RESULTS: Clearly abnormal cycles were found in only two women in the older age group, and in one woman in the younger group. The main differences between the age groups were a shorter follicular phase and cycle length in the older group, in combination with higher FSH levels in the late luteal and early follicular phase. In contrast to published data which suggest an "accelerated" follicle development in older women, sonographical and hormonal evidence was found of an "advanced" follicle growth, with an earlier start already during the luteal phase of the preceding cycle, and an advanced selection and ovulation of the dominant follicle. CONCLUSIONS: Such an earlier start of follicle growth in a possibly less favourable hormonal environment, as well as a limited oocyte pool, may contribute to a decreased follicle and oocyte quality, resulting in diminished fertility in ageing women.     

Infant feeding with soy formula milk: effects on puberty progression, reproductive function and testicular cell numbers in marmoset monkeys in adulthood

BACKGROUND: This marmoset study addresses concerns about feeding human male infants with soy formula milk (SFM). METHODS: From age 4 to 5 days, seven male co-twin sets were fed standard formula milk (SMA) or SFM for 5-6 weeks; blood samples were subsequently collected at 10-week intervals. Testes from co-twins killed at 120-138 weeks were fixed for cell counts. RESULTS: SFM- and SMA-fed twins showed normal weight gain; puberty started and progressed normally, based on blood testosterone measurements. Body weight, organ weights (prostate, seminal vesicles, pituitary, thymus and spleen) and penis length were comparable in co-twins. All SMA- and 6/7 SFM-fed males were fertile. Unexpectedly, testis weight (P = 0.041), Sertoli (P = 0.025) and Leydig cell (P = 0.026) numbers per testis were consistently increased in SFM-fed co-twins; the increase in Leydig cell numbers was most marked in males with consistently low-normal testosterone levels. Seminiferous epithelium volume per tubule showed a less consistent, non-significant increase in SFM-fed males; raised germ cell numbers per testis, probably due to increased Sertoli cells, conceivably resulted in larger testes. Average lumen size, although greater in SFM-fed group, was inconsistent between co-twins and the difference was not significant. CONCLUSIONS: Infant feeding with SFM has no gross adverse reproductive effects in male marmosets, though it alters testis size and cell composition, and there is consistent, if indirect, evidence for possible 'compensated Leydig cell failure'. Similar and perhaps larger changes likely occur in adult men who were fed SFM as infants.     

Role of estrogen and progesterone in the regulation of uterine peristalsis: results from perfused non-pregnant swine uteri

BACKGROUND: Adequate uterine contractility and peristalsis are involved in the transport of semen and gametes and in successful embryo implantation. Estrogen and progesterone fluctuate characteristically during the menstrual cycle. It has been suggested that both hormones influence uterine peristalsis in characteristic ways. METHODS: An extracorporeal perfusion model of the swine uterus was used that keeps the uterus in a functional condition and is suitable for the study of physiological questions. The effects of estrogen and progesterone on oxytocin-induced uterine peristalsis were assessed using an intrauterine double-chip microcatheter. RESULTS: Estrogen perfusion was associated with an increase in intrauterine pressure (IUP) in a dose-dependent manner. There was a significant difference between the IUP increase measured in the isthmus uteri and that in the corpus uteri, resulting in a cervico-fundal pressure gradient. Estrogen perfusion resulted in a significantly higher rate of peristaltic waves starting in the isthmus uteri and directed towards the corpus uteri. Progesterone was able to antagonize the estrogen effect in general. CONCLUSIONS: This study demonstrates that estrogen and progesterone have differential effects in the regulation of uterine peristalsis. The present observation shows that estrogen stimulates uterine peristalsis and is able to generate a cervico-fundal direction of peristalsis, whereas progesterone inhibits directed uterine peristalsis.     

Time to pregnancy as a function of male and female serum concentrations of 2,2'4,4'5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE)

BACKGROUND: Persistent organochlorine pollutants (POP) may affect both the female and male reproductive system in animals as well as in humans. METHODS: Blood samples were collected from pregnant women and their partners from Greenland, Warsaw and Kharkiv, and from a cohort of Swedish fishermen's wives. Blood samples were analysed for 2,2',4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p'-DDE). Information on the participants' fertility, measured as time to pregnancy (TTP), was collected. In total, 778 men and 1505 women were included in the analyses. RESULTS: The data from Warsaw, Kharkiv and the Swedish fishermen's wives indicated no effect of either male or female exposure to POP on TTP. However, among men and women from Greenland, there seemed to be an association between serum concentrations of CB-153 and p,p'-DDE and prolonged TTP. Due to the strong intra-individual correlation between CB-153 and p,p'-DDE in the Greenlandic population, it was not possible to determine whether the risk was associated with CB-153 or p, p'-DDE or was an interaction between the two compounds. CONCLUSIONS: The overall results of the present study create a somewhat ambiguous pattern, but give some support to the idea that dietary POP exposure might be harmful for couple fertility.     

Prostasomes--their effects on human male reproduction and fertility

The prostate is a glandular male accessory sex organ vital fornormal fertility. It provides the prostatic component of seminalplasma which nourishes and protects sperm following ejaculation.Prostasomes are small (40–500 nm) membrane-bound vesiclesproduced by epithelial cells lining the prostate acini and area component of prostatic secretions. Although the existenceof these particles has been known for many years, their fullfunction and relevance to reproductive health are largely unknown.Proteomic studies have shown a wide range of proteins (enzymes,structural proteins and novel, unannotated proteins) presentin or on the surface of prostasomes providing them with a diversenature. Interestingly prostasomes are able to fuse with sperm,this event and the associated transfer of proteins lies at theheart of many of their proposed functions. Sperm motility isincreased by the presence of prostasomes and their fusion preventspremature acrosome reactions. Prostasomes have been shown toaid protection of sperm within the female reproductive tractbecause of immunosuppressive, antioxidant and antibacterialproperties. Clinically these functions imply a role for prostasomesin male factor infertility. However, the very functions thatpromote fertility may have negative connotations in later life;recent work has suggested that prostasomes are involved in prostatecancer. Clearly more work is needed to clarify the role of thesenovel particles and their impact on men’s health.     

Chances of pregnancy after dropping out from infertility treatments: Evidence from a social survey in Japan

PurposeWe examined a patient''s chances of pregnancy after dropping out from infertility treatments, an issue that has been largely understudied.MethodDrawing from a nationwide Internet survey in Japan with 1930 respondents, we used data from 199 individuals (109 women and 90 men) who had undergone an infertility treatment. We estimated linear probability models to investigate the extent to which the probability of pregnancy was affected by dropping out after controlling for a couple''s attributes.ResultsAmong the 199 respondents who had experienced an infertility treatment, 91 (45.7% of the entire sample) became pregnant during the treatment, and 108 (54.3%) dropped out. Among these 108 dropouts, 66 (33.2%) eventually became pregnant. After controlling for a couple''s attributes, treatment discontinuation reduced the probability of pregnancy by 31.6% (standard error: 5.0%). A relatively limited reduction in the chances of pregnancy was also observed after a patient dropped out of any of the three treatment stages (timed intercourse, intrauterine insemination, and in vitro fertilization).ConclusionsThe results suggest that dropping out from infertility treatments does not preclude any chance of a future pregnancy. More follow‐up attention should be provided to dropout patients.     

Ovarian tissue grafting: Lessons learnt from our experience with 55 grafts

Purpose

Uncertainties remain regarding the clinical efficacy of ovarian tissue cryopreservation and grafting. We report a retrospective analysis of reproductive outcomes and lessons learnt following 55 ovarian tissue transplant procedures at our center from 2006 to 2019.

Methods

We analyzed variables related to graft success such as tissue volume, follicular density, total follicular volume, and age on the duration of graft function.

Results

Follicular density and total follicular volume correlate positively with duration of graft function. All clinical pregnancies in our cohort occurred in women who were aged 35 or less at the time of ovarian tissue cryopreservation.

Conclusion

Graft success, as determined by eventual pregnancy and the longevity of graft function, may be impacted by factors including age at cryopreservation, follicular density, and total follicular volume.

     

重视女性生育调控与生殖健康

计划生育的基本内涵是有计划的生育调控,在我国实行独生子女政策时突出避孕节育这一工作重点.在新时期的人口和生育政策环境下,计划生育被赋予了新的内涵且回归到计划生育学本真之中,在避孕节育的基础上更加注重提高育龄女性生殖健康水平,为育龄期女性提供包括避孕节育和优生优育指导、生育力评估、不孕症诊治、疾病防治等全方位、全周期、多...