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PubMed2004

FFPRHC Guidance (January 2004). The copper intrauterine device as long-term contraception.

This Guidance provides information for clinicians providing women with copper-bearing intrauterine devices as long-term contraception. A key to the grades of recommendations, based on levels of evidence, is given at the end of this document. Details of the methods used by the Clinical Effectiveness Unit (CEU) in developing this Guidance and evidence tables summarising the research basis of the recommendations are available on the Faculty website (www.ffprhc.org.uk). Abbreviations (in alphabetical order) used include: acquired immune deficiency syndrome (AIDS); actinomyces-like organisms (ALOs); automated external defibrillator (AED); blood pressure (BP); British National Formulary (BNF); confidence interval (CI); copper-bearing intrauterine contraceptive device (IUD); emergency contraception (EC); Faculty Aid to Continuing Professional Development Topic (FACT); levonorgestrel-releasing intrauterine system (IUS); human immunodeficiency virus (HIV); Medicines and Healthcare products Regulatory Agency (MHRA); non-steroidal antiinflammatory drugs (NSAIDs); odds ratio (OR); pelvic inflammatory disease (PID); relative risk (RR); Royal College of Obstetricians and Gynaecologists (RCOG); Scottish Intercollegiate Guidelines Network (SIGN); sexually transmitted infection (STI); termination of pregnancy (TOP); World Health Organization (WHO); WHO Medical Eligibility Criteria (WHOMEC); WHO Selected Practice Recommendations (WHOSPR).

Consumer Product Safety↗
PubMed1982

Role of daylength in the regulation of reproductive function in the male mongoose, Herpestes auropunctatus.

The male mongoose, Herpestes auropunctatus, displays a distinct seasonal reproductive rhythm in environments which show minimal changes in daylength. This investigation was designed to evaluate whether the reproductive system of the male mongoose was responsive to photoperiodic manipulations. Four experiments were conducted; two during the breeding season, one during the inactive season, and one during the recrudescence phase. Serum androgen levels and reproductive organ weights were similar in males exposed to either short (6L:18D) or control photoperiods (14L:10D) when the photoperiodic adjustment was initiated in April; however, serum androgen levels were significantly depressed after 60 days exposure to short photoperiods as were weights of prostate glands when the photoperiodic manipulation was initiated in May. An increase in the number of hours of light per day during the inactive season did not affect serum androgen levels or reproductive organ weights. Exposure to a very short photoperiod (2L:22D) during the recrudescence phase delayed, but did not prevent, the increase in serum androgen levels. Although the reproductive system of the male mongoose is responsive to daylength adjustments, the response is less pronounced when compared to the effects of photoperiod in other seasonal breeders.

Androgens↗
PubMed1988

Effects of subchronic inhalation of D-D (1,3-dichloropropene/1,2-dichloropropane) on reproduction in male and female rats.

The effects of inhaled D-D (1,3-dichloropropene/1,2-dichloropropane) on reproduction were studied in rats of both sexes. The rats inhaled nominal concentrations of 0, 10, 30, or 90 ppm (v/v) D-D for 6 hr/day, 5 days/week for 10 weeks. Treated males of proven fertility were paired with untreated virgin females at intervals during and after exposure. Treated females were paired with untreated males immediately after the 10-week exposure period. Various aspects of reproductive performance and general toxicity were assessed. Exposure to D-D produced no adverse effects on the libido, fertility, or morphology of the reproductive tracts of rats of either sex; no treatment-related dominant lethal effect was observed in male rats. Slight reductions in body weight gains and slight increases in liver and kidney weights were observed in 90 ppm rats of both sexes.

Allyl Compounds↗
PubMed1979

Effects of restrictive suckling on postpartum reproductive performance in mares.

Quarter Horse mares (n = 30) and their foals were used in a 2-year study. Objectives of the study were (i) to determine the effects of a treatment regimen, which permitted nursing for four 1-hour periods each day, on the postpartum reproductive performance of the dams, and (ii) to assess the effects of this procedure on the growth and development of foals. Mares in the restricted suckling treatment group showed estrus and ovulated sooner (P less than 0.01) after parturition than did control mares during the first year of the study, but not during the second year. Plasma progesterone concentrations were similar for both treated and control mares and remained less than 1 ng/ml from parturition to ovulation. Conception rates were not significantly influenced by treatment. However, two mares which had records of failing to have estrus while nursing a foal were bred and ovulated, and one of the two conceived while on the restricted suckling treatment. The absence of treatment effects on any of the variables measured in the foals indicates that restricted suckling did not impair foal growth and development.

Animals↗
PubMed2000

Biochemical and morphological diversity among folliculo-stellate cells of the mink (Mustela vison) anterior pituitary.

The folliculo-stellate (FS) cells are agranular cells of the anterior pituitary whose origin and function are still a matter of debate. This study examined the presence, topography, and morphological characteristics of FS cells in the mink anterior pituitary throughout the annual reproductive cycle. The S-100 protein was used as a FS cell marker. Immunoperoxidase labeling on tissue sections demonstrated the presence of two types of S-100 positive cells. Type 1 cells were stellate-shaped cells whose nuclei were localized near the center of pituitary follicles. In this type, S-100 labeling was strong in anterior pituitary sections obtained during spring, a period characterized by high prolactin pituitary content and low gonadotropin pituitary content. Type 2 cells were rounded cells occupying the periphery of the follicles. During periods of low prolactin pituitary content and high gonadotropin anterior content the type 2 S-100 positive cells formed aggregates of several cells. The total number of S-100 positive cells was constant during these two periods of the annual reproductive cycle, suggesting that type 1 and type 2 may reflect different morphological and physiological states of the same cell. Of the two subunits, alpha and beta, that, combined, form three different dimeric S-100 proteins, mink FS cells expressed mostly the beta subunit. FS cells also expressed the glial fibrillary acidic protein (GFAP). In culture, 8 +/- 3% of anterior pituitary cells were S-100 positive. Cultured S-100 cells were elongated, polygonal, or rounded. The S-100 labeling accumulated in the cytoplasm around and within the nucleus, whereas it was weak in pseudopods and large cytoplasmic vacuoles. The presence of pseudopods suggests that cultured FS cells could migrate. The vacuoles may be related to the phagocytic activity ascribed to these cells. Some FS cells presented membrane blebbing and peripheral vesicles that were immunopositive for S-100 and that may indicate a secretory activity. Cultured FS cells possessed actin filaments organized as a peripheral network; a few actin cables were also observed running across the cytoplasm. Pseudopods depicted a highly organized actin network. The microtubules of FS cells expanded throughout the cytoplasm. The intermediate filaments expressed by cultured FS cells were GFAP and vimentin. GFAP labeling was punctate and vimentin was organized as filaments. All cultured S-100 cells were positive for vimentin, suggesting a mesenchymal origin for the cells, and all cultured S-100 positive cells were positive for GFAP, suggesting a neuroectodermal origin. In conclusion, S-100 positive cells are heterogeneous with respect to cell shape and expression of S-100 subunits in the mink anterior pituitary. The presence of morphologically different S-100 positive cells is modified in accordance with the endocrine status of the animal, suggesting that FS cells may be involved in the modulation of the anterior pituitary endocrine activity in the mink.

Animals↗
PubMedDate not supplied

Influence of photoperiod, ambient temperature and melatonin on testosterone synthesis and release during reproductive maturation in male deer mice.

Four experiments were designed to investigate the influence of photoperiod and other environmental factors on androgen production and reproductive maturation in deer mice. Male prairie deer mice (Peromyscus maniculatus), born in a light/dark cycle of 6L:18D, either remained in this short photoperiod or were switched to a long day regimen of 16L:8D at weaning. In a cross-sectional experiment, the deer mice were killed between 3 and 8 weeks of age for measurement of serum testosterone concentration and reproductive organ weights. In a second experiment, blood was collected from each mouse at weekly intervals between 3 and 9 weeks of age. This repeated measures design was used to reduce the high variability in testosterone values observed in the first experiment. Reproductive organs were weighed at the termination of the experiment. Testosterone concentrations and reproductive organ weights were greater in males reared in the long photoperiod in both experiments. In a third experiment, the animals were housed under five different conditions to test the influence of high ambient temperature and melatonin as well as photoperiod. At 7 weeks of age, they received an injection of hCG or saline. More testosterone was released in deer mice reared in 16L:8D and 27 C than in those reared in short days (6L:18D) or those reared in high ambient temperature (35 C) or those treated with exogenous melatonin. One week later, animals were sacrificed. The single hCG treatment caused significant reversal of the suppression of accessory sex organ weights following melatonin, short days or 35 C temperature. In a fourth experiment, the additive influence of melatonin and 35 C temperature was tested. Animals treated with 35 C or both melatonin and 35 C had lower serum testosterone at 7 weeks of age, released less testosterone after hCG, and had smaller organ weights with or without hCG than long day controls. The influence of melatonin treatment and 35 C temperature appears to be additive for testicular weight and testosterone release after hCG. Thus, the attenuation of reproductive development that accompanied short days, melatonin treatment and high ambient temperature occurred via diminished testosterone secretion, which can be overcome at least in part by gonadotropin treatment.

Animals↗
PubMed2004

Reproductive performance before and after abdominal myomectomy: a retrospective analysis.

OBJECTIVE: To evaluate the results of abdominal myomectomy for intramural and subserosal fibroids and to identify factors that influence the reproductive outcome after surgery. DESIGN: Retrospective analysis of a case series. SETTING: An academic department specializing in gynecologic surgery. PATIENT(S): A total of 72 women with intramural and subserosal fibroids submitted to abdominal myomectomy who wished to conceive after surgery. INTERVENTION(S): Data were collected on clinical characteristics, surgical features, and obstetric history before and after surgery. MAIN OUTCOME MEASURE(S): Conception rate, pregnancy loss, and live birth rate before and after surgery, as well as postoperative probability of conception according to selected clinical and fibroid characteristics. RESULT(S): Conception rate was 28% before myomectomy and 70% after surgery. The corresponding figures were 69% and 25% for pregnancy loss and 30% and 75% for live birth rate, respectively. Age <30 years and number of fibroids removed were the only significant and independent predictors of obstetric outcome by multivariate analysis. CONCLUSION(S): Our results suggest that abdominal myomectomy might improve reproductive outcome in patients with intramural and subserosal fibroids. The reproductive performance was particularly good when the patients were younger than 30 years and had a single myoma to remove.

Abortion, Spontaneous↗
PubMed1992

Reproduction and maternal nutrition in Madura, Indonesia.

The prevalence and severity of chronic energy deficiency (CED) among women of reproductive age as well as its consequences on the newborn and the mother were assessed in a longitudinal study. More than 40% of the mothers had a Body Mass Index (BMI) less than 18.5 before pregnancy, a level below which CED is considered to exist. Weight gain during pregnancy was low, on average 6.6 kg. Taking the difference between 4 week postpartum weight and pre-pregnant weight as net weight gain during pregnancy, mothers with a BMI less than 18.5 before pregnancy gained weight while those with a higher BMI lost weight. This observation suggests that the partitioning of energy to the fetus and the mother depends on the energy reserves of the mother before pregnancy. The functional significance of BMI as an indicator of CED is illustrated by its relation with birth weight. Similarly, 4 week postpartum, weight and BMI were predictive for the weight changes in the mother in the first 12 months after delivery. The groups with the lowest values gained weight, while the heaviest mothers lost weight. In view of the negative effects of CED among women of reproductive age on the infant and the mother, maternal undernutrition should receive the same attention as malnutrition among preschool children.

Body Weight↗
PubMed1986

An assessment of reproductive wastage in sheep.

Reproductive wastage was evaluated by relating ovulation rate to lambs born or raised in range finewool ewes over a ten-year period. The results indicate that reproductive losses are of large magnitude and that these losses are concentrated in the period of ovulation to implantation and in death losses of lambs born. In this study, 33.5% of the potential lamb crop was lost in the early period. Multiple ovulating ewes showed the greatest embryonic loss. The data do not deviate from the binomial distribution, thus suggesting that these losses are largely due to chance. Further work is indicated in the first seventeen days after ovulation to examine losses due to fertilization failure, chromosomal abnormalities, and implantation failure. Abortion or absorption of the fetus was indicated in only 4% of the ewes sampled. An average of 16% of the potential lamb crop was lost from birth to weaning, with 73% of these losses occurring in the first few weeks. Management practices need to be developed to reduce these losses, and these would be expected to vary from one producer to the next depending on conditions. Increasing ovulation rate is one possible method of improving reproductive efficiency, as results of this study indicate that for each unit increase in ovulation rate, there is an increase of 0.52, 0.46, 0.33, and 0.23 in the average number of embryos surviving, lambs born, lambs marked and lambs weaned, respectively.

Journal Article↗
PubMed2000

Reproductive management of postpartum cows.

High reproductive efficiency in the dairy cow requires a disease-free transition period, high submission rates to AI and high pregnancy rates per service. A key risk factor that causes increased incidence of metabolic disease is low negative energy balance (NEB) in the periparturient and early postpartum periods. Low NEB decreases LH pulse frequency, growth rate and diameter of dominant follicle (DF), IGF-I, glucose, insulin concentrations and increases GH and certain blood metabolites; these effects result in greater loss of body condition score (BCS) and a higher percent of anoestrous cows in the herd. It is important to decrease the incidence of metabolic disease by achieving high dry matter intake (DMI) and minimising the period of NEB after calving. Thus, nutritional management of the cow in the transition period has a crucial role to play in improving reproductive efficiency, because acute nutritional deprivation of heifers has immediate deleterious effects on follicular growth and ovulation. To obtain high submission rates, it is necessary to decrease the incidence of anoestrus and to have good oestrous detection rates. Pregnancy rates per service are affected by a variety of factors. NEB can have deleterious effects on the follicle or the corpus luteum (CL) by decreasing IGF-I concentrations and steroidogenesis. High protein diets fed to postpartum cows leads to increased blood urea and lower fertility. Although the mechanism is not clear, the practical implication of feeding the appropriate level of crude protein in the diet is clear. Thus, a coordinated management approach involving herd managers, nutritionists and veterinarians is required to obtain high reproduction efficiency in dairy cows.

Animal Husbandry↗
PubMed1982

The measurement of urinary steroid glucuronides as indices of the fertile period in women. World Health Organization, Task Force on Methods for the Determination of the Fertile Period, special programme of research, development and research training in human reproduction.

The concentrations of various estrogen glucuronides and pregnanediol-3 alpha-glucuronide have been measured in daily samples of early morning urine (EMU) and 24 h pooled collections throughout a total of 70 menstrual cycles (58 subjects). The immediate objective was to identify and assess the potential value of measuring hormone metabolites to locate the fertile period in women, with the ultimate aim of developing a non-invasive immunochemical test. The project was undertaken in five centres and the results showed that: (i) there was good agreement in the patterns and mean concentrations of metabolites between the centres; (ii) estrone-3-glucuronide should be the estrogen glucuronide selected for further study; (iii) the analysis of EMU provided information that was as useful as the corresponding measurements on pooled collections for 24 h; (iv) a rise in the concentration of estrone-3-glucuronide (50% over the mean of three preceding values) could be used to locate the start of the fertile period in greater than 90% of the ovarian cycles (from day LHmax -- 3 to day LHmax -- 7); attempts to locate the end of the fertile period by a threshold value or a defined rise in the level of pregnanediol-3 alpha-glucuronide were disappointing. A 50% rise over the mean of three preceding values in the derived concentration ratio of estrone-3-glucuronide/pregnanediol-3 alpha-glucuronide could be used to indicate the start of the fertile period, and a 50% decrease plus two days the start of the infertile period in greater than 80% of the ovarian cycles. The limitations, implications and future developments are discussed.

Adolescent↗
PubMedDate not supplied

Spontaneous recovery from ethanol-induced male infertility.

Chronic ethanol ingestion by the male is associated with reproductive impairment. 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% ethanol diet (10 weeks) or a 6% ethanol diet (5 weeks), animals were 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 testicular weights (24% and 28%, respectively) and seminal vesicle/prostate weights (20%, 6% diet only), increased frequencies of germ cell desquamation (480% and 400%), inactive seminiferous tubules (186% and 567%) 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 was a significant decrease in total motile spermatozoa (85%, 6% diet only). Improvement in all parameters was observed in the contralateral reproductive organs subsequent to ten 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 persisted ten weeks after treatment with the 6% ethanol diet, including increased germ cell desquamation (200%) and inactive seminiferous tubules (157%); decreased forward progression (17%) of epididymal sperm also persisted. If these data can be applied clinically, male alcoholic patients with reproductive disorders could have a prognosis of at least partial recovery following moderate periods of abstinence from ethanol.

Animals↗
PubMed1983

The annual reproductive cycle in mallards.

In wild mallard drakes plasma FSH and LH levels were elevated at the height of the breeding season in spring, decreased towards the end of the reproductive phase and were low during the time of photorefractoriness in summer, when the testes were regressed. In contrast plasma prolactin concentrations increased only towards the end of the breeding season and were at their annual height during the summer. Castration of photorefractory mallards caused a steep rise of plasma LH levels indicating that the testes were involved in the maintenance of the low LH concentrations during the refractory period. In these drakes LH titers remained high throughout the year and, thus, in the absence of the testes the birds did not become photorefractory. In photorefractory drakes removal of 90% of the testicular tissue not only increased plasma LH levels but induced complete spermatogenesis in the testicular remains within 6 weeks. Therefore it seems that photorefractoriness in mallards is due to an increased sensitivity of the hypothalamo-hypophyseal system to the negative feedback action of testicular androgens. After injection of tritiated testosterone the hypothalamus, anterior pituitary and testes, but not other organs studied, took up more radioactivity during the refractory phase than at the height of the breeding season. It is speculated that the increased sensitivity of the hypothalamo-hypophyseal unit to the negative androgenic feedback during photorefractoriness depends on an increased number of androgen receptors in these structures which, again, could be due to the elevated prolactin levels during this phase of the annual cycle.

Animals↗
PubMed1992

Seasonal prolactin secretion and its role in seasonal reproduction: a review.

The majority of seasonally breeding mammals show a seasonal pattern of prolactin secretion with peak concentrations in spring or summer and a nadir in autumn or winter. Photoperiod influences prolactin secretion via its effects on the secretion of the pineal hormone melatonin. Preliminary evidence suggests that the effects of melatonin on both prolactin and gonadotrophin secretion are via a common target area, possibly within the anterior hypothalamus, and that differences in response to photoperiod may be due to differences in the processing and/or interpretation of the melatonin signal. In contrast to seasonal gonadotrophin secretion, the seasonal changes in prolactin are not due to changes in the sensitivity of a feedback loop and so must be due to direct effects on the hypothalamic pathways that control prolactin secretion. Little else can be said with confidence about the neuroendocrine mechanisms that lead to the seasonal changes in prolactin secretion. Dopamine and noradrenaline turnover in the arcuate nucleus and median eminence decrease under short daylength. If catecholamine turnover in these structures is positively correlated with catecholamine concentrations in the long or short hypophysial portal vessels, it is unlikely that the decrease in prolactin concentration in winter is due to the effects of increased concentrations of dopamine or noradrenaline in the portal vessels. There is, however, evidence for increased pituitary sensitivity to dopamine under short daylength, so increased dopamine concentrations may not be required for suppression of prolactin secretion at this time. In addition to the diminished secretion of prolactin under short daylength, rate of prolactin synthesis and pituitary content of prolactin also decline although the mechanisms that regulate these changes are poorly understood. Although all seasonal breeders show a seasonal change in prolactin secretion, there are continuously breeding species in which prolactin secretion is also under photoperiodic control. It is likely therefore that a seasonal pattern of prolactin secretion is only evidence of neuroendocrine sensitivity to changing photoperiod. Depending upon the species, this sensitivity to the seasonal changes in daylength may or may not be accompanied by seasonal changes in a biological endpoint such as seasonal reproduction or indeed other adaptations. Whether the seasonal change in prolactin secretion is an endocrine mediator of such adaptations remains in contention. Certainly in some species this signal does have a role in reproduction. For example, in species with an obligate seasonal embryonic diapause, the seasonal increase in prolactin can act as a luteotrophin (mink and western spotted skunk) or luteostatin (Bennett's and tammar wallabies.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1997

The hypothalamic-pituitary-adrenal axis and the female reproductive system.

The hypothalamic-pituitary-adrenal (HPA) axis and the female reproductive system are intertwined and exhibit a complex relationship. Thus, the HPA axis exerts profound, mostly inhibitory effects, on the reproductive axis, with corticotropin-releasing hormone (CRH) and CRH-induced propiomelanocortin peptides inhibiting hypothalamic GnRH secretion, and with glucocorticoids inhibiting pituitary LH and ovarian estrogen and progesterone secretion and rendering estrogen-target tissues, such as the endometrium, resistant to the gonadal steroid. These effects of the HPA axis are responsible for the "hypothalamic" amenorrhea of stress, depression and eating disorders, and the hypogonadism of Cushing's syndrome. Conversely, estrogen directly stimulates the CRH gene, which may explain the slight hypercortisolism of females and the preponderance of depressive, anxiety, and eating disorders, as well as Cushing's disease in women. Interestingly, several components of the HPA axis and their receptors are present in reproductive tissues, as autocoid regulators of their various functions. These include ovarian and endometrial CRH, which may participate in the inflammatory processes of the ovary, that is, ovulation and luteolysis, and of the endometrium, that is, implantation and menstruation. Finally, the hypercortisolism of the latter half of pregnancy can be explained by high levels of placenta CRH in plasma. This hypercortisolism causes a transient adrenal suppression in the postpartum period, which may explain the postpartum blues/depression and autoimmune phenomena of this period.

Corticotropin-Releasing Hormone↗
PubMed2000

Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats 27). Repeated toxicity study on ethylene glycol monomethyl ether for 2 and 4 weeks to detect effects on male reproductive organs in rats.

As part of a collaborative project to determine the minimum administration period to detect compound effects on male reproductive organs in Sprague-Dawley (Crj:CD(SD)) male rats, 6- and 8-week-old rats were administered ethylene glycol monomethyl ether (EGME) daily at 100 and 200 mg/kg/day for 2 weeks or 100 mg/kg/day for 4 weeks, and histopathological changes in the testes and epididymides were examined. Testis and epididymis weights in the 2-week 200 mg/kg and 4-week 100 mg/kg groups were obviously decreased. On histopathological examination, severe degenerative changes in the testis such as atrophy of the seminiferous tubules and multinucleated giant cell formation were observed in all 2-week 200 mg/kg group rats. Degeneration of pachytene spermatocytes in Stages X IV-II, III and a decrease in the number of germ cells was observed with both 2 and 4 weeks treatments at 100 mg/kg/day. In the epididymides, the number of sperm in the caput decreased with 100 mg/kg/day groups after both 2 and 4 weeks. In addition, degeneration of pachytene spermatocytes induced by EGME was found to be exclusively due to apoptotic death. Similar testicular and epididymal changes were observed with 2 and 4 weeks treatments at 100 mg/kg/day of EGME. Therefore, we conclude that a 2 weeks administration period is sufficient for detection of EGME effects on male reproductive organs.

Administration, Oral↗
PubMed1992

[The sexual behavior of the primates].

The article presents the review of modern data of the field and laboratory investigations of primate sexual behavior, cyclicity, reproductive strategies and copulation in different primates taxa: strepsirrhini, platyrrhyni, catarrhini. The specific character, progressiveness and adaptation of some reproductive models are discussed by the authors. A problem of connection between dominance and reproductive success is also discussed, the role of sexual teaching in postnatal ontogenesis, age and hormonal status for expression of sexual behavior are analysed. Some forms of sexual declinations in primates are considered.

Aging↗