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Low fertility rate in vasovasostomized males and its possible immunologic mechanism.

Contradictory views have been expressed about the role of the various antisperm antibodies which develop after vasoligation. The present study was conducted in 50 normal fertile males, 50 vasectomized subjects and 25 subjects after recanalization of their vas deferens in order to investigate the development of various anti-sperm antibodies after vasectomy, along with their incidence, their persistence after successful relief of vaso-obstruction by vasovasostomy and their role in the causation of infertility in vasoanatomized normospermia males. Sperm agglutinating, immobilizing and haemagglutinating antibodies showed rises in titres with increase during the post-vasectomy period, indicating continuous antigenic stimulus. Age, post-operative complications and blood group did not seem to alter the results. 86% of subjects developed antisperm agglutinins, mostly tail-to-tail type (54.5%), 1-12 years after vasoligation, while only 2% of fertile men had circulating spermagglutinins. A lower incidence of positive sperm in the immobilization test than in the agglutination test suggests either that different antibodies are detected by these two tests or these tests have differing sensitivities. Of the 25 vasovasostomized subject, 13 (52%) cases became normospermic and 4 (16%) oligospermic while 8 (32%) remained azoospermics. Except for 3 oligospermic subjects, all had circulating spermagglutinins. Among the 13 normospermic vasovasostomized persons, a significant correlation was found between the titres of circulating antisperm agglutinins and autoagglutination of spermatozoa in their ejaculates; and also between the sperm immobilization values of their sera and the degree of their sperm motility. Three normospermic recanalized men, having low levels of sperm agglutinins and haemagglutinins with normal seminogram and no sperm immobilizing antibody, successfully impregnated their wives. Another 10 vasovasotomized infertile subjects had sperm agglutinins in significant titre; 5 showed positive sperm immobilization values, a similar number showed autoagglutination of sperm, while a decreased degree of motility of sperms was noted in 6 cases. Thus there was a significant correlation between the titres of anti-sperm antibodies and autoagglutination of spermatozoa, which might be an important cause of male infertility after successful anatomic relief of vasoobstruction. Histological studies of testicular biopsy showed normal spermatogenesis in azoospermic recanalized subjects, although they had high levels of antisperm antibodies. This suggests that these antibodies do not affect normal spermatogenesis, and sperm counts.

Adult

An analysis of stallion fertility rates (foals born alive) from the breeding documents of the Landgestüt Celle over a 158-year period.

An evaluation of the foaling rate achieved in the Hannoverian breed in Germany between 1815 and 1973 showed that during this period no improvement of the reproductive rate was achieved. The decennial foaling percentage remained within 50--60% except for those decades which included the two World Wars and their aftermaths. The annual foaling percentage remained maximal until the number of mares covered/stallion rose above 80 and it also remained high throughout the reproductive life of the stallion. Only in the oldest stallion (32 years) was there a significant lowering of fertility.

Animal Husbandry

Role of dextran 70 in microtubal surgery.

Pelvic adhesion formation represents a major problem following fallopian tube surgery for infertility. Intraperitoneal dextran may prevent pelvic adhesions. Extensive personal clinical experience (W. H. U.) with intraperitoneal dextran organ-flotation on completion of tubal and ovarian surgery has appeared to limit adhesions. A specific study was designed to test the validity of this theory. Four randomized groups of rabbits were subjected to bilateral tubocornual division and microsurgical reanastomosis with total hemostasis and pelvic lavage. Routine peritoneal closure was performed on one group, but followed instillation of 30 to 50 ml of normal saline into the peritoneal cavities of the second group, and 30 to 50 ml of 6% dextran 70 into those of the third. Study of fourth group, which received 32% dextran 70 in the peritoneal cavity, was discontinued because of complications. A second laparotomy was performed 4 weeks later for precise assessment and photography of adhesion formation. Each animal was mated 4 weeks after the second operation in order to determine fertility rates. Reduced adhesion formation and increased fertility rates following the instillation of dextran are reported. A role for dextran 70 in infertility surgery is recommended.

Animals

Quantitative aspects of marriage, fertility and family limitation in nineteenth century America: another application of the Coale specifications.

This paper deals with three aspects of the decline in the fertility of white women in the United States from 1800 to 1920. The first concerns the portion of the secular decline in the total fertility rate which was due to changes in marriage rates and the portion due to decreases in marital fertility rates. The second concerns the fraction of couples in the nineteenth century who acted effectively to reduce their fertility and the third deals with the importance of abortion as a family-limiting practice among white couples in the nineteenth century.

Abortion, Induced

IVM rescue: Effect of growth hormone supplementation combined to autologous cumulus co-culture on GV oocyte maturation and competency.

OBJECTIVE: IVM rescue is based on the in vitro maturation of mainly Germinal Vesicle (GV) oocytes collected from stimulated cycles. The objective was to investigate the effects of growth hormone (GH) and autologous cumulus cells co culture (CC) on oocyte meiosis resumption and maturation after 32 h post cumulus denudation, in order to obtain additional embryos for the couple as a rescue system to increase the changes of cumulative pregnancy. MATERIAL AND METHODS: Our study concerned 300 patients who underwent ICSI cycles, during which a total of 1940 cumulus-complex-oocytes were retrieved, giving 1260 metaphase II stage (MII), 200 at the metaphase I stage, and 480 at the Germinal Vesicle (GV) stage. Mature oocytes were microinjected on the same day of retrieval. Immature GV oocytes were divided into four groups, with the first undergoing in vitro maturation (IVM) without cumulus cells (group 1) and the second undergoing IVM with CC (group 2), the third undergoing IVM without CC and with GH (group 3), the fourth undergoing IVM with CC and with GH (group 4). After 32 h of IVM, the matured oocytes, underwent microinjection, followed by embryonic development monitoring. RESULTS: When comparing the IVM outcomes, we observed a significant increase in oocyte maturation, fertilization rates and the percentage of 8-cell embryos on day 3 across the different study groups (p < 0.001) (Figs. 2-5). Furthermore, all study groups (1-4) exhibited notably blastulation rates, with group 3 demonstrating the most promising clinical outcomes. A preliminary pregnancy rate of approximately 20% was recorded in group 3, suggesting a potential improvement in the developmental competence of oocytes matured under specific conditions. CONCLUSION: The IVM rescue of germinal vesicle oocyte could serve as an additional strategy to increase the chance getting extra embryos to patients. Autologous cumulus cells co-culture combined to GH supplementation to IVM media, appear to play a crucial role to enhance successful meiosis resumption, oocyte maturation and competency to support embryos development when the injected spermatozoa is not carrier of severe genome and epigenomic decays.

Humans

Parenting styles and fertility intention: Mediating effects of childbearing beliefs and psychological resilience.

China's declining fertility rate is partly due to low fertility intention among childbearing population. To understand family influence on young people's fertility intention and its underlying mechanisms, this study examines how parenting styles (authoritarian vs. permissive) affect Chinese college students' fertility intention, with traditional childbearing beliefs and resilience as mediators. Data were collected from 839 participants (Age: M = 21.1, SD = 1.7 years) using structured questionnaires. Logistic regression found that a positive correlation between permissive parenting style and fertility intention, with authoritarian parenting having no impact. Mediation analysis showed the association between permissive parenting style and fertility intention was fully mediated through resilience (&#xf062; = 0.0, 95%CI = [0.0,0.1]) and greater childbearing beliefs (&#xf062; = 0.0, 95%CI = [0.0,0.1]). The findings indicate that permissive parenting is related to higher fertility intention in youth via resilience and childbearing beliefs. Promoting positive family environments and permissive parenting may enhance childbearing intention.

Humans

Effect of long- and short-term intravaginal progestagen treatments on synchronization of oestrus and fertility in heifers.

A total of 273 Herford cross heifers were treated with intravaginal progestagen pessaries to determine some of the factors affecting oestrous response and fertility following long-term (20-day) and short-term (10-day) treatments. Oestrous response and degree of synchronization were high after treatment for 20 days, but the fertility rate was lower than that of control heifers. There was no difference in the fertility of heifers inseminated artificially and those mated naturally. When the treatment period was reduced to 10 days and 900 mg progesterone and 5 mg oestradiol valerate given intramuscularly at the start, a high oestrous response and a low degree of synchronization resulted, but the conception rate was similar to that of the control animals. Reducing the dose of progesterone to 250 mg resulted in a high oestrous response and a high degree of synchronization. The stage of the cycle at the start of the 10-day treatment did not affect the oestrous response. Retention of the progesterone pessary was low (79-9%) in heifers treated for 2- days, but was 100% in those treated for 10 days.

Animals

A fertility reaction to a historical event: southern white birthrates and the 1954 desegregation ruling.

On 17 May 1954 the Supreme Court, in its decision in Brown v. Board of Education, declared de jure segregation of the public schools to be unconstitutional. It is argued here that a consequence of that decision was a decline in childbearing among white Southerners. In the nation as a whole, period fertility rates increased between 1954 and 1955, but in 9 of the 11 former Confederate states they decreased. Further analysis shows that these Southern fertility decreases began about 12 months after the Supreme Court decision. This variation in behavior in reaction to a historical event has important implications for the explanation and prediction of fertility.

Birth Rate

Cryptorchism.

Our results from 121 patients as well as data from the literature prove that fertility rates after treatment of uni- or bilateral cryptorchism remain unsatisfactory. There is no statistically significant difference in fertility between a group of patients treated with human-chorionic-gonadotrophin and another group treated by orchidopexy after unsuccessful hormonal therapy. On the other hand, late results in unilateral cryptorchism are to a statistically significant extent better than in bilateral cryptorchism (46/29%). According to our histological findings in maldescended testicles, early treatment (before the age of 3 years) is advocated.

Age Factors

Antipain and leupeptin restrict uterine DNA synthesis and function in mice.

As in rats, administration of estradiol to ovariectomized mice results in a trypsin-like proteolytic activity in the uterus. After fractionation of uteri from estradiol-treated ovariectomized mice the protease activity was found in the 12,000 times g pellet and the nucleus, appearing first in the former. Further fractionation of the pellet by discontinuous sucrose gradient centrigugation resulted in sedimentation of the protease with 5'-nucleotidase, a marker enzyme for plasma membrane and separate from mitochondrial and lysosomal enzyme markers. Solubilization was best accomplished by lysis at 37 degrees. The soluble enzyme from mouse uterus had optimal activity at about 43 degrees and pH 8.3 and was inhibited by diisopropylfluorophosphate, tosylarginine methyl ester, antipain, and leupeptin, but not by soybean trypsin inhibitor. Inhibition in vitro by antipain and leupeptin, two low molecular weight peptides, prompted the study of their effect in vivo on the mouse uterus. After intact, cycling female mice received subcutaneous injections of antipain and leupeptin for 16 days, their uteri showed significant diminution in weight and total DNA when compared to untreated controls. Fertility rates were also diminished. Trypsin-like protease activity may be essential to normal uterine metabolism and function.

Animals

Effect of the fungal toxin (zearalenone) on the reproductive system and fertility of male and female rats.

The fertility-inhibiting effects of long-term (8 weeks) consumption of maize infected with a fungus producing F2 toxin (zearalenone) was studied in adult male and female albino rats. The fertility rate was further decreased by 25-30% if the animals were kept on contaminated diet up to 14 weeks. The gonadal weight was decreased, follicular maturation and spermatogenesis were disturbed. The toxic diet consumed by mothers during pregnancy and lactation induced permanent changes in reproductive organs, disorders in vaginal cyclicity and disturbed fertility in the offspring. Neonatal administration of purified F2 toxin provoked similar changes. It is suggested that this fungal toxin may cause sterility syndrome in the offspring, similar to that produced by androgen or estrogen administration.

Animals

Fertility patterns after discontinuation of use of oral contraceptives.

Investigation of the fertility-rate after discontinuation of use of oral contraceptives shows that the monthly rate consistently follows an oscillatory pattern. This pattern appears to be unique to women who have discontinued the use of oral contraceptives. It may result from synchronisation of a previously unrecognised natural cycle, rebound changes in the reproductive system following steroidal contraception, or an infertile period associated with early intrauterine mortality.

Adult

Murine cytomegalovirus and fertility: potential sexual transmission and the effect of this virus on fertilization in vitro.

Male mice were inoculated with murine cytomegalovirus (MCMV) to produce an acute generalized infection. Infections virus was recovered from both epididymal sperm and seminal vesicles as well as from uterine sperm collected from mated females, suggesting that MCMV might be transmitted sexually. Because the presence of virus in the ejaculate might affect the fertilization process, the effect of MCMV on the fertilization of mouse gametes and on subsequent embryonic development was studied in vitro. Although the fertilization rate was reduced when sperm were preincubated with infectious virus, this was also the case when heat-inactivated virus was used, leading to the conclusion that this effect was not due to a direct infectious interaction between virus and gametes. Subsequent embryonic development was normal, and there was no evidence of productive infection of the preimplantation embryo.

Animals

The ante-natal detection of Down's syndrome: some demographic aspects.

The numbers of Down's syndrome live births in the area covered by the Sheffield Regional Hospital Board (Trent Regional Health Authority) were estimated using age specific incidence data from a recent detailed Swedish study. The estimated number and proportion of Down's syndrome live births, which could have been detected by prenatal screening of elderly mothers at high risk, fell substantially in recent years. In the maternal age group forty to forty-four the estimated number of Down's syndrome livebirths decreased from thirty-three (24.6 per cent) in 1963 to thirteen (15.7 per cent) in 1973. Over the same period there was a fall in estimated numbers in the thirty-five to thirty-nine age group from twenty-seven (20.2 per cent) to twelve (14.5 per cent). This trend has been due predominantly to a rapid decline in the fertility rates of women aged thirty-five and over. However, projections based on the best available evidence suggest that about 11.4 per cent to 13.8 per cent of all Down's livebirths up to 1991 could be detected by screening all pregnancies in the forty to forty-four age group. A further 11.7 per cent to 14.4 per cent of Down's livebirths could be detected by screening pregnancies in the thirty-five to thirty-nine age group.

Abortion, Induced

[Optimal time for treating cryptorchism (author's transl)].

In a ten-year span (1950-1960) a total of 133 patients were operated upon for maldescent of testes. A follow-up enquiry traced 102, of whom 79 were re-examined. Maldescent had been unilateral in 71, bilateral in eight. All of the latter were infertile. In the others the fertility rate was the greater the younger the patient at the time of operation, best results being noted in those operated upon during the first or second year of life. Acquired testicular disorders seemed to play a minor role, while the normally descended contralateral testis was apparently damaged in an as yet undetermined manner (autoantigen-antibody reaction?) It is concluded that the optimal moment for operating on testicular maldescent is (at the latest) the end of the second year of life.

Adolescent