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PubMed1989

[State of the reproductive function in women with hyperandrogenism and miscarriage in the immediate period and long-term follow-up].

A study was made of 180 females aged 22-58 years with a history of premature labor secondary to high levels of androgen. The ovarian pattern of the disease was stated in 21 per cent (group I), mixed in 49 per cent (group II) and adrenal, in 30 per cent of examinee s (group III). In 69.4 per cent, the pregnancy ended in the delivery of a viable fetus. Recovery of reproductive function was a failure in 30.6 per cent of the patients (group II mainly). Longitudinal study revealed the dependence of menstrual and generative functions both on the disease pattern and outcome of the previous pregnancy. The most unfavourable prognosis for the further progression of reproductive dysfunction was made for females with ovarian or mixed patterns of the disease therefore they might be considered as a risk-group.

Abortion, Habitual↗
PubMed1988

Inbreeding effects on fertility and hatchability associated with the formation of sublines.

The deleterious effect of inbreeding on fertility and hatchability was studied in a population of Leghorns developed primarily for immunogenetics studies. The 1983 population averaged 42% inbreeding and traced back to only two sires and five dams of the 1965 base population. Up to 1975 (Period 1), the population was maintained as a single-unit closed flock, during which time inbreeding increased an average of 1.44% per year. After 1975 (Period 2), the population was split into five sublines. Inbreeding then increased at the average rate of 2.7% per year. The regression of fertility on inbreeding was -.31 +/- .04 in Period 1 and -.17 +/- .06 in Period 2. Corresponding values for hatchability of fertile eggs were +.08 +/- .05 in Period 1 and -.24 +/- .07 in Period 2. The regression of hatchability of total eggs set was -.15 +/- .04 in Period 1 and -.35 +/- .10 in Period 2. The evidence implies that both fertility and hatchability have a heritable basis. As expected, the deleterious effects of inbreeding on reproduction was more severe in Period 2, with sublining.

Animals↗
PubMed1985

Partial reversal of ethanol-induced male reproductive pathology following abstinence.

To date, no longitudinal studies have been carried out to determine the recovery of ethanol-related reproductive failure subsequent to moderate periods of abstinence. An animal model (C57B1 mouse) was utilized to examine the effectiveness of abstinence for reversal of ethanol-induced reproductive failure. After treatment with either a 5% (v/v) ethanol diet (10 weeks) or a 6% (v/v) ethanol diet (5 weeks), ethanol-treated animals and their pair-fed controls were electroejaculated and hemicastrated (right testis and accessory organs); their reproductive tracts and epididymal spermatozoa were examined. Ingestion of the 5% and 6% ethanol diets resulted in significantly (P less than 0.05) decreased weights of testes (24% and 28%, respectively) and seminal vesicles/prostate (20%, 6% diet only), increased frequencies of germ cell desquamation (480% and 400%), inactive seminiferous tubules (186% and 567%), sperm dysmorphology (31% and 119%) and inhibition of in vitro fertilization of mouse oocytes by epididymal spermatozoa (26% and 62%), as compared to their respective pair-fed control values. Also observed were significant decreases in epididymal sperm content (72%, 6% diet only), total motile spermatozoa (85%, 6% diet only) and seminal vesicles epithelial cell height (13% and 29%). No abnormal semen parameters were observed after treatment with the 5% ethanol diet; however, in animals treated with the 6% diet, significant decreases were noted in coagulum weight (50%), sperm count (85%) and acid phosphatase content (53%). Improvement in all parameters was observed in the contralateral half of the reproductive tract subsequent to 10 weeks abstinence. Only germ cell desquamation remained significantly elevated (100% as compared to control) in animals that ingested the 5% diet. In contrast, significant abnormalities persisting 10 weeks after treatment with the 6% ethanol diet included increased germ cell desquamation (200%), inactive seminiferous tubules (157%) and sperm dysmorphology (39%) and decreased forward progression (17%) of epididymal sperm, as compared to values. These findings are discussed in relation to the influence of alcohol consumption on male reproductive function in man.

Animals↗
PubMed1994

Investigation of a spontaneous abortion cluster: lessons learned.

An investigation of a reported spontaneous abortion excess in an office environment was undertaken employing a multidisciplinary approach, including (1) an epidemiologic/validation step; (2) an industrial hygiene survey, including electromagnetic field measurements and indoor air quality determinations; and (3) a risk perception/risk communication component. This approach was needed because there are numerous chemical and physical agents and psychosocial stressors that may potentially impact the reproductive status of female office workers. Although video display terminals (VDTs) are typically the focus of spontaneous abortion (SAB) investigations, one cannot ignore other stressors in the environment. Magnetic field exposures within a payroll area were determined using a hand-held survey meter and data logging dosimeter. On average, the full shift time-weighted average exposures of workers to extremely low frequency (ELF) magnetic fields in the payroll office area ranged from 1.0 to 5.6 mG. Influencing the investigation's protocol design were the Centers for Disease Control's (CDC's) recent Guidelines for Investigating Clusters of Health Events. Although these guidelines grew primarily out of cancer cluster investigations, we applied them in this instance and found them to be generalizable to reproductive hazards investigations. A spontaneous abortion excess was validated over a 2-year period among 26 women with 32 reproductive events, with rates 1.5-2.5 times the expected, depending on comparison figures used. Lessons learned in the investigation, including the applicability of the CDC's Cluster Investigation Protocol and the enormous importance of risk perception and risk communication, are described.

Abortion, Spontaneous↗
PubMed1996

Predictors of ovarian steroid secretion in reproductive-age women.

During the baseline period (1985-1988) of a prospective study, midcycle and luteal-phase estrogens and progestins were measured in 175 healthy women aged 21-36 years with spontaneous, cyclic menses in Brooklyn, New York. Subjects contributed daily first-morning urine specimens and three blood specimens during a single menstrual cycle monitored by basal body temperature. Hormone levels were compared according to age, race, and levels of known or suspected breast cancer risk factors. Late age at menarche was associated with increased urinary and serum progestin levels. Increased body weight was associated with decreased progestin levels, even in ovulatory women. Neither weight nor age at menarche was related to estrogen levels. Cigarette smoking was associated with decreased midcycle and luteal-phase estradiol levels. No other factors were associated with differences in any of the hormones measured either midcycle or during the luteal phase, despite good statistical power to detect moderate differences. Sources of individual variability in ovarian steroid levels remain unexplained. These data do not support hypotheses that breast cancer risk factors act through an effect on ovarian hormones during the middle reproductive years.

Adult↗
PubMed1988

Causes of maternal mortality in rural Bangladesh, 1976-85.

Of a total of 1037 women of reproductive age who died during the period 1976-85 in the Matlab area that was under demographic surveillance, 387 (37%) were maternal deaths. The mean maternal mortality over the 10-year period was 5.5 per 1000 live births (101 per 100 000 women of reproductive age). Major causes of maternal death, which were assessed using a combination of record review and field interviews, included postpartum haemorrhage (20%), complications of abortion (18%), eclampsia (12%), violence and injuries (9%), concomitant medical causes (9%), postpartum sepsis (7%), and obstructed labour (6.5%). Deaths caused by postpartum haemorrhage were positively associated with both maternal age and parity, whereas those caused by eclampsia and injuries were more common among young and low-parity women. If maternal deaths arising from complications of abortion are disregarded, 20% of all maternal deaths occurred during pregnancy, 44% during labour and the two days following delivery, and 36% during the remaining postpartum period.These findings support the need to develop a service strategy to address the risks of childbearing and childbirth in areas such as rural Bangladesh, where almost all deliveries take place at home. This strategy must be based not only on preventive and educational interventions, including family planning and antenatal care, but also on systematic attendance at home deliveries by trained professional midwives, backed up by an effective chain of referral.

Abortion, Spontaneous↗
PubMed1988

[Reproduction studies of carboplatin (II)--Intravenous administration to rats during the period of fetal organogenesis].

Carboplatin, an oncostatic drug, was administered intravenously to pregnant Crj: CD (Sprague-Dawley) rats from day 7 through 17 of gestation at dose levels of 1, 2 and 4 mg/kg/day. The summarized results obtained are as follows: 1. Carboplatin 4 mg/kg suppressed the maternal body weight gains from day 13 through 20 of gestation. 2. Uterine weights were reduced in F0 dams at term at carboplatin 4 mg/kg. 3. Carboplatin 4 mg/kg brought the inhibition of fetal growth accompanied by the lowered values in fetal weights, crown-rump distances and tail lengths. Furthermore, the elevated incidences of unossified 5th and 6th sternum , as well as retarded ossification of sacrococcygeal vertebrae were also noted in this dose level. 4. The birth rate was reduced in neonates (F1) at carboplatin 4 mg/kg. 5. Body weight gains in male F1 rats were suppressed at carboplatin 4 mg/kg from 4 to 8 weeks of age. 6. Carboplatin 4 mg/kg decreased the brain weights on an absolute basis in female F1 rats, but failed to affect their postnatal differentiations, early behavioral developments, learning ability, motor activity or emotional development. 7. Reproductive ability in F1 rats of both sexes were not affected by carboplatin. 8. Influences on prenatal development were not apparently observed for F2 fetuses derived from F1 rats whose dams had ever received carboplatin during the organogenetic period. Based on these results, the no-effect dose level of carboplatin under the present experimental condition was estimated to be 2 mg/kg/day against dams and their offspring.

Animals↗
PubMed2004

Effect of copper, zinc, and manganese supplementation and source on reproduction, mineral status, and performance in grazing beef cattle over a two-year period.

Crossbred, multiparous beef cows (n = 178 in Year 1; n = 148 in Year 2) were used to evaluate the effects of Cu, Zn, and Mn supplementation and source on reproduction, mineral status, and performance in grazing cattle in eastern Colorado over a 2-yr period. Cows were stratified by expected calving date, age, BW, BCS, and liver mineral status and assigned to the following treatments: 1) control (no supplemental Cu, Zn, or Mn); 2) organic (ORG; 50% organic and 50% inorganic Cu, Zn, and Mn); and 3) inorganic (ING; 100% inorganic CuSO4, ZnSO4, and MnSO4). Free-choice mineral feeders were used to provide current NRC-recommended concentrations of Cu, Zn, and Mn from 82 d (Year 1) and 81 d (Year 2) before the average calving date of the herd through 110 d (Year 1) and 135 d (Year 2) after calving. At the end of Year 1, supplemented cows had greater liver Cu (P < 0.01), Zn (P < 0.05), and Mn (P < 0.01) concentrations compared with controls, whereas liver Cu concentration was greater (P < 0.01) in ORG vs. ING cows. At the end of Year 2, supplemented cows had greater (P < 0.01) liver Cu concentrations relative to controls, whereas control cows had greater (P < 0.02) liver Mn concentration than did supplemented cows. In Year 1, pregnancy rate to AI in control cows did not differ (P = 0.47) from supplemented cows, but there was a trend (P < 0.08) for pregnancy rate to be higher for ORG than ING cows. In Year 2, supplemented cows had a higher (P < 0.02) pregnancy rate to AI than controls. In both years, when cows were inseminated after an observed estrus, supplemented cows had a higher (P < 0.04) pregnancy rate than did controls. Also, for both years, overall 60-d pregnancy rate tended (P = 0.10) to be higher for supplemented cows than for controls. In Year 1, kilograms of calf weaned per cow exposed was greater (P < 0.02) in controls than in supplemented cows, and kilograms of calf weaned per cow exposed was greater (P < 0.01) in ING than ORG treatments. However, in Year 2, kilograms of calf weaned per cow exposed was greater (P < 0.02) in controls than in supplemented cows, and tended (P = 0.09) to be greater in ORG than ING treatments. Results indicate that supplementation and source of trace minerals affected mineral status and kilograms of calf weaned per cow exposed in grazing beef cows. Supplementation also improved pregnancy rate to AI compared with cows not supplemented with Cu, Zn, or Mn for more than 1 yr. Furthermore, mineral source may influence pregnancy rate to AI.

Age Factors↗
PubMed1989

Long-term reproductive cycles in rams after pinealectomy or superior cervical ganglionectomy.

Long-term cycles in diameter of the testes, colouration of the sexual skin and plasma concentrations of testosterone, FSH and prolactin were monitored in groups of pinealectomized (PINX), superior cervical ganglionectomized (SCGX), and control Soay rams living near Edinburgh (56 degrees N). In Exp. 1, PINX, SCGX and control rams were kept outside for 4 years, and well defined seasonal cycles in each of the reproductive parameters were evident in all 3 groups (e.g. testosterone cycle length assessed by sine-wave analysis: 12.08 +/- 0.17, 12.39 +/- 0.14 and 12.15 +/- 0.10 months for PINX, SCGX and control rams respectively). Qualitative differences, however, were apparent between the groups in the timing and amplitude of the reproductive cycle. The seasonal peak in reproductive function occurred from July to September in the PINX and SCGX rams, some 2 months earlier in the year than in controls, while the amplitude of the cycle was less marked in the PINX and SCGX rams. There were no significant differences between the experimental groups in the seasonal cycle in the plasma concentrations of prolactin. In Exp. 2, SCGX and control rams were kept indoors under an artificial environment with a 32-week light cycle and constant nutrition for 4 years. Compared to the controls, in which the reproductive changes were synchronized to the driving light cycle, the SCGX rams showed poorly defined reproductive cycles of lower amplitude and longer period (e.g. testosterone cycle length: 57.8 +/- 6.1 and 32.1 +/- 0.2 weeks for SCGX and control rams, respectively). There was evidence of a cycle in some of the reproductive parameters in the SCGX rams with a period close to 32 weeks during the second half of the study (e.g. testosterone cycle 32.4 +/- 0.8 weeks), which was taken to indicate social induction from the neighbouring control rams. In two further short-term experiments, SCGX rams showed a decline in testicular activity in response to receiving a restricted diet (60% of controls) and an increase in testosterone secretion in response to exposure to oestrous ewes. The overall results illustrate that PINX and SCGX rams can generate long-term synchronized cycles in pituitary and testicular activity. The animals are apparently unable to respond to changes in daylength due to the loss of the functional pineal gland but they remain competent to respond to other environmental cues such as changes in nutrition, temperature and social factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

[Cytogenetic study in disorders of human reproduction].

We reviewed 1347 cytogenetic studies performed in a period of eight years to analyze chromosomal translocations and their relation with reproductive failure. Twenty nine index cases were detected representing a global incidence of 2.2% thirteen (45%) were balanced reciprocal translocations between autosomes, thirteen (45%) were robertsonian translocations and three (10%) were X; autosomal translocations. The most frequent indication for the study were, for each group, respectively, recurrent abortion, a child with congenital malformations and ovarian dysfunction. Our results are compared with those of other authors and the mechanisms and figure risks for unbalanced offspring are discussed.

Abnormalities, Multiple↗
PubMed1975

Exogenous and endogenous control of the annual reproductive cycle in the male golden hamster: participation of the pineal gland.

Testes and accessory sex organs (seminal vesicles and coagulating glands) of hamsters exposed to natural lighting (NL) conditions beginning September 22 underwent complete degeneration by October 31. The following February the testes began to regrow with the regeneration being complete by mid to late March. Associated with the atrophic response of the testes during the winter months was consistent depression in pituitary prolactin and an inconsistent decrease in pituitary luteinizing hormone levels. If hamsters are pineal lectomized prior to their exposure to NL, the sexual organs do not atrophy and the pituitary hormone levels do not drop. Moving hamsters from NL to the long daily photoperiods (light:dark cycles of 14 hrs light and 10 hrs darknessLD 14:10) of the laboratory near mid winter is followed by regrowth of the gonads and accessory glands. Regeneration of the reproductive system in the spring is not a function of increasing photoperiodic length since if animals are completely deprived of light (by blinding) in February, the gonads still regenerate. When hamsters are exposed to LD 14:10 cycles during the subsequent summer, the return to NL on September 22 is followed by a second involution of the reproductive system. However, if the period of LD 14:10 (the simulated summer) is shortened by ten weeks, the second return to NL does not initiate involution of the reproductive system. During the simulated summer complete light deprivation by blinding is incapable of forcing atrophy of the sexual organs.

Animals↗
PubMed2001

Parallel speciation: a key to sympatric divergence.

Until recently, our view of speciation was that reproductive isolation evolves during long periods of allopatry through the accumulation of genetic differences that result in genetic incompatibility. This view now contrasts with new findings that characters affecting reproductive isolation can diverge rapidly in sympatry as a result of natural selection. Recent studies combining research on phylogeny and ecology of natural populations cast new light on patterns, timescales and mechanisms, and emphasize the role of ecological factors in speciation. Studies of parallel speciation provide a strong case for sympatric speciation and for natural selection generating reproductive barriers.

Journal Article↗
PubMed1984

Reproductive performance of Bhotia women of Mana Valley.

This paper reports the preliminary findings on the reproductive performance of 52 Bhotia women from the Mana Valley (Uttar Pradesh; elevation 10 560 ft.), who had approached menopause. The total amount of time available for reproduction and the total time used for effective reproduction as well as the period, which has been wasted as a result of sociocultural and biological factors, have been calculated. The total time available to Bhotia women for reproduction is found to be 1584 years, out of which 1563 years (98.67%) were used for effective reproduction. The reproductive wastage as a result of socio-economic and biological circumstances is calculated as 21 years only or 0.40 years per woman. All pregnancies as well as lactation operate to reduce fecundability. The various family limiting methods also lower the reproductive performance. A comparison has been made with the results of similar studies in other populations.

Abortion, Spontaneous↗
PubMed1987

Reproductive activity in Finnish Landrace x Rambouillet ewes exposed to various daylength cycles applied over periods of six months.

Twenty-six Finnish LandracexRambouillet ewes were exposed to a series of artificial daylength cycles over periods of 6 mo. The cycles in general consisted of 3 mo. of long or increasing daylength, followed by 3 mo. of short or decreasing daylength. Increasing daylength to 22 hr.; 17.5 hr. or 15.75 hr. but not 14 hr. resulted in the onset of anestrus in all ewes. Only four of eight ewes in the 14 hr. cycle became anestrus. Abrupt decreases in daylength resulted in a more rapid return to reproductive cyclicity than a gradual decline. In addition, there appeared to be an inverse relationship between the length of the longest day of a treatment cycle and the time taken for ewes to return to reproductive cyclicity, following a subsequent abrupt decrease in daylength. Reducing daylength form 22 hr. to 17.5 hr. did not induce reproductive cyclicity. Reducing daylength from 17.5 hr. to 15 hr.; 12.75 hr. or 7.5 hr. did result in the onset of reproductive cyclicity. Finally, extending the period of long day exposure in a daylength cycle decreased the response time to a subsequent reduction in daylength. It was concluded that reproductive seasonality may be initiated by the interaction of darkness with a daily photosensitive phase in the ewe.

Journal Article↗
PubMed2006

Long-term non-hormonal male contraception in mice using N-butyldeoxynojirimycin.

BACKGROUND: The imino sugar N-butyldeoxynojirimycin (NB-DNJ) causes reversible infertility in male mice. This compound may have promise as a male contraceptive, because it is already in clinical use, for a non-reproductive condition. As contraceptives need to be taken for extended periods of time, it was essential to evaluate NB-DNJ for its reproductive effects over a long period of administration. METHODS: We have assessed the imino sugar for its long-term effects on the fertility of male C57BL/6 mice, reversibility and potential cumulative toxicity by monitoring various reproductive and systemic parameters over 12 months. RESULTS: Long-term low-dose (15 mg/kg/day) administration of NB-DNJ was sufficient to maintain infertility in male mice. In contrast to short-term drug treatment, imino sugar exposure for more than 3 months resulted in reduced sperm counts. Male mice that had been administered imino sugar for 6, 10 or 12 months and were then maintained without drug administration regained their fertility within 9 weeks after withdrawal of the drug. Prolonged NB-DNJ intake did not affect reproductive hormone levels, serum biochemistry or animal behaviour. CONCLUSION: Low-dose treatment with NB-DNJ over a long period is an effective approach for the regulation of fertility in a male mammal by non-hormonal means, without causing overt adverse effects.

1-Deoxynojirimycin↗
PubMed2003

Transition cow: interaction with fertility.

In recent years a progressive worsening of fertility indices in dairy cow herds has been observed. Several factors (genetic, dietary and management) seem to be more related to poor fertility than milk yield level. The degree and the length of the energy deficit during the transition period are inversely related to reproductive indices (e.g. conception rate is <30% for BCS decreases over one unit). A serious energy deficit reduces (or suppresses) pulsatile secretion of gonadotrophins (ovarian dysfunction and/or smaller follicles): IGF-I and insulin plasma levels (slower follicle growth and higher embryonic mortality); and progesterone production from the corpus luteum (higher rate of embryonic abortions). The diet influences fertility in several ways. Excess of rumen degradable proteins, apart from negative energy balance, negatively affects reproductive activity. Conversely, some nutrients (i.e. some polyunsaturated fatty acids or some amino acids) seem to show positive effects on fertility. Finally, the relationship between health status, often compromised during the transition period, and fertility efficiency is discussed. The release of cytokines seems to be related directly and indirectly (mainly by the change in usual hepatic metabolism to the malfunction of reproductive apparatus. Quick recovery of reproductive activity requires the adoption of strategies around calving to cover the higher environmental and nutritive requirements and to prevent disorders of any kind.

Animals↗
PubMed1997

The effect of dietary protein on reproduction in the mare. IV. Serum progestagen, FSH, LH and melatonin concentrations during the anovulatory, transitional and ovulatory periods in the non-pregnant mare.

The effect of total protein intake and protein quality on the serum concentrations of certain reproductive hormones during the anovulatory, transitional and ovulatory periods were studied in 36 Anglo-Arab mares. High-quality protein stimulated FSH and LH production during the late transitional period. Serum progestagen and melatonin concentrations were unaffected by the quality of protein nutrition during the anovulatory period. Mares receiving high-quality protein exhibited a 10-14-day cyclical pattern of FSH release approximately 4-6 weeks earlier than the mares fed the lower-quality protein diet, and also ovulated 3-4 weeks earlier than the mares on the lower-quality protein diet. Progesterone concentrations during the 1st oestrous cycle after the anovulatory period were unaffected by protein quality in the diet.

Analysis of Variance↗