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PubMed2002

Wisdom, casuistry, and the goal of reproductive counseling.

Reproductive counseling includes counseling of prospective parents by obstetricians, clinical geneticists, and genetic counselors regarding, for example, the use of assisted reproductive technologies, prenatal testing, and preimplantation genetic diagnosis. Two different views on wisdom and the goal of reproductive counseling are analyzed. According to the first view, the goal of reproductive counseling is to help prospective parents reach a wise decision. A specific course of action is recommended by the counselor in contrast to other possible alternatives. According to the second view, the goal of reproductive counseling is not to help prospective parents reach a wise decision but to help them reach their own decision wisely. It is the prospective parents who should make the decision, and it is their value commitments that should be decisive. It is argued that the second approach is to be preferred to the first. It combines respect for autonomy with a recognition of the need for assistance in decision-making. Both the first and second views relate the goal of reproductive counseling to wisdom. A problem is, however, what wisdom more precisely means - there are many different views. A casuistic view of wisdom is investigated. This view roughly defines wisdom as practical prudence in dealing with particular cases. What characterizes a casuistic decision-making method is elaborated in more detail. Applied to the second view, a casuistic view of wisdom implies that the counselor should encourage prospective parents to take into consideration the nature of the particular problem at hand, the context of the problem, their own individual identities, their personal value commitments, and various alternative perspectives, values and arguments.

Counseling↗

PubMed1995

Reproductive research on farm animals for Australia--some long-distance goals.

In Australia, much of the research on the reproduction of farm animals has emphasised the technological manipulation of the reproductive tract, gametes and embryos. However, most of the animal production in Australia is still based on sheep and beef cattle enterprises that are managed on an extensive scale; the managers need technologies that can be easily and cheaply implemented on a large scale, and that are aimed at extensive control rather than intensive manipulation. For example, for synchronizing oestrus in the wool flocks the "ram effect' has, and probably always will have, far more impact on extensive grazing systems than technologies based on exogenous prostaglandins or progestagens. This can also apply to the newer animal industries (such as emu farming), to human problems (such as population control), and to environmental problems (such as control of feral animals). Moreover, under the pressure of public opinion, the industries that are currently intensive are going 'free range'. In addition, surgical managerial tools (such as castration) will probably have to be abandoned or replaced. To cope with such profound influences, new types of reproductive management systems will be needed. This paper is an attempt to broaden our research horizons by developing the concept of 'control systems technologies', aimed at controlling reproductive performance rather than simply improving it. Ideas for such technologies already exist and are evident in the responses to environmental factors that our farm animals developed under the pressure of natural selection (before domestication). Stress, nutrition, photoperiod, lactation, and socio-sexual cues (e.g. pheromones) can all exert profound effects on reproductive activity. We already have a good grasp of the final common pathway through which the brain responses to these factors affect gonadal activity, namely the hypothalamic system that generates pulses of gonadotrophin-releasing hormone. All we need to do is learn how the major environmental cues exert their impact on the systems that control the final common pathway. When we understand them, we shall be able to manipulate them. This is not too speculative; we already have several technologies that take advantage of this approach, including steroid-based contraceptives, the "ram effect', a vaccine-based antifertility treatment for rangeland cattle and the melatonin formulation used to control seasonal breeding in sheep. These and the other pathways linking environmental inputs to reproductive output are waiting to be explored, explained and exploited.

Animals↗

PubMedDate not supplied

Nurses' description and evaluation of reproductive health counseling for adolescent females.

Nurses have been providing reproductive health counseling to adolescent females for over 20 years. Yet, we found no studies in the nursing literature in which the investigator examined the types of reproductive health counseling nurses provide to adolescent females. Therefore, the purpose of this study was to examine nurses' description and evaluation of the types of reproductive health counseling they used for adolescent females. Five registered nurses, with at least 10 years experience in providing reproductive health counseling to adolescent females, were interviewed using a semi-structured guide. Four areas were explored: type of information provided, barriers to providing counseling, adolescent female decision-making capacity, and nursing recommendations. Two general themes emerged from the respondents' evaluations: frustration and unused potential of nurses to affect the reproductive health of adolescent females, and the inappropriateness of current reproductive health strategies for adolescent females.

Adolescent↗

PubMed2001

Linkage of reproductive sciences: from 'quick fix' to 'integrated' conservation.

Our laboratory has experienced four phases in understanding how the reproductive sciences contribute to genuine conservation of biodiversity. The first is the 'quick fix phase' in which the erroneous assumption is made that extant knowledge and techniques are readily adaptable to an unstudied wild animal to produce offspring rapidly. The second is the 'species-specificity phase' in which it is recognized that every species has evolved unique reproductive mechanisms that must be mastered before propagation can be enhanced. The third is the 'applicability phase' in which one grasps that all the new knowledge and technology are of minimal relevance without the cooperation of wildlife managers. The final phase is 'integration', the realization that reproduction is only one component in an abundantly complex conservation puzzle that requires interweaving many scientific disciplines with elaborate biopolitical, economic and habitat variables. These phases are illustrated using 20 years of experience with wildlife species, including the cheetah, black-footed ferret and giant panda. We conclude that the foremost value of the reproductive sciences for conserving endangered species is the discipline's powerful laboratory tools for understanding species-specific reproductive mechanisms. Such scholarly information, when applied holistically, can be used to improve management by natural or, occasionally, assisted breeding. Genuine conservation is achieved only when the reproductive knowledge and technologies are integrated into multidisciplinary programmes that preserve species integrity ex situ and preferably in situ.

Acinonyx↗

PubMed2002

Developments in judicial approaches to sexual and reproductive health.

This article reviews the jurisprudence on reproductive and sexual health of national and international tribunals. This review reveals a shift from controlling reproduction and sexuality through the use of criminal law to impose a moral order, to the use of administrative law to ensure availability of safe and effective services, and, finally, to the use of human rights to promote respect for human dignity. The conventional use of criminal law to prohibit provision of reproductive and sexual health services, underage sex, and relations between same-sex partners is waning. Due in part to research showing how criminal law harms reproductive health, an emerging judicial trend is toward the more pragmatic use of law to reduce the harm to health associated with sexuality and reproduction. Most recently, courts are recognizing that respect for individuals' needs to protect their reproductive and sexual health is a matter of social justice.

Adolescent↗

PubMedDate not supplied

International human rights and women's reproductive health.

Neglect of women's reproductive health, perpetuated by law, is part of a larger, systematic discrimination against women. Laws obstruct women's access to reproductive health services. Laws protective of women's reproductive health are rarely or inadequately implemented. Moreover, few laws or policies facilitate women's reproductive health services. Epidemiological evidence and feminist legal methods provide insight into the law's neglect of women's reproductive health and expose long-held beliefs in the law's neutrality that harm women fundamentally. Empirical evidence can be used to evaluate how effectively laws are implemented and whether alternative legal approaches exist that would provide greater protection of individual rights. International human rights treaties, including those discussed in this article, are being applied increasingly to expose how laws that obstruct women's access to reproductive health services violate their basic rights.

Cross-Cultural Comparison↗

PubMed2002

Reproductive health indicators and outcomes among refugee and internally displaced persons in postemergency phase camps.

CONTEXT: Despite increasing awareness of the importance of reproductive health programs and services for refugee and internally displaced populations, there is a paucity of basic epidemiological data on reproductive health outcomes. OBJECTIVES: To collect data on reproductive health outcomes among refugees and internally displaced persons in postemergency phase camps and compare these outcomes with those of host country and country-of-origin populations. To determine programmatic factors that may affect reproductive health outcomes. DESIGN, SETTING, AND PARTICIPANTS: Retrospective study of data collected from August 1998 through March 2000 of 688,766 persons living in 52 postemergency phase camps in 7 countries. Reproductive health outcomes of refugee and internally displaced populations were compared with available data of reference populations within their respective host country and country of origin. MAIN OUTCOME MEASURES: Crude birth rate (CBR), neonatal mortality rate (NNMR), maternal mortality ratio (MMR), percentage of newborns with low birth weight (LBW), and incidence of complications of unsafe or spontaneous abortions. RESULTS: Six of 11 groups had lower CBRs than their country of origin and 5 of 9 groups had lower CBRs than their host country. Four of 5 had lower NNMRs than their country of origin and 6 of 9 had lower NNMRs than the host country. Four of 6 had lower MMRs than their country of origin, and 5 of 6 had lower MMRs than their host country. Seven of 9 had lower percentages of LBWs than in the country of origin and 5 of 9 had lower percentages of LBWs than the host country. Higher CBRs were associated with more recently established camps and higher numbers of local health staff per 1000 persons; and higher percentages of LBW newborns were associated with rainy season, more recently established camps, lower numbers of community health workers per 1000 persons, and camps without supplementary feeding programs. CONCLUSIONS: Refugees and internally displaced persons in most postemergency phase camps had better reproductive health outcomes than their respective host country and country-of-origin populations.

Abortion, Illegal↗

PubMed1999

Reproductive biology of female titi monkeys (Callicebus moloch) in captivity.

Titi monkeys (Callicebus spp., Cebidae) are monogamous neotropical primates that live in family-like groups typically consisting of an adult monogamous pair and one or two young. Knowledge about the reproductive biology of this genus is scanty. This study investigated the reproductive biology of female dusky titi monkeys (Callicebus moloch). An initial analysis characterized reproductive parameters of 32 females from a captive colony maintained for 23 years at the California Regional Primate Research Center (CRPRC). The colony records provided data on reproductive parameters such as interbirth intervals, seasonality, age at first pregnancy, and reproductive rate in captivity. Changes in urinary levels of estrone conjugates (E1C) and pregnanediol-3alpha-glucuronide (PdG) were used to characterize major reproductive events. Urine samples from eleven females were collected during 17 months. The endocrine data were used to examine changes associated with cycling, conception, and the post-partum period as well as to determine the duration of the ovarian cycle and gestation length. The analysis of colony records indicated that females whose infant survived through weaning gave birth at intervals remarkably close to one year, while those who lost their offspring showed a significantly shorter interval. As long as they lived within the family group, mature female offspring did not breed. The analysis of the endocrine profiles indicated that after giving birth to a viable offspring, females undergo a relatively prolonged period of anovulation (approx. 6.5 months), followed by 1-3 non-conceptive cycles (approx. 1 month), after which they conceive and gestate (4.3 months).

Animals↗

PubMed2001

Constant light and blinding effects on reproduction of male South Indian gerbils.

The effects of exposure to constant light (CL) and blinding on male reproductive behavioral physiology of South Indian gerbils (Tatera indica cuvieri) were assessed. Exposure to CL diminished reproductive efficiency of males with a reduction in the proportion of ejaculating males. This is further evidenced by increase in the number and duration of intromissions and intromission latency. Concomitantly, reproductive organ weight and epididymal sperm count were also reduced. However, in weanlings CL did not induce changes either in their maturational process or their reproductive organs' weight. Blinding of adult reproductively inactive males resulted in a considerable proportion of them exhibiting sexual activity, which is reflected in the seminal vesicle weight and epididymal sperm count. Blinded weanlings showed earlier testicular descent and higher seminal vesicle weight. These studies reveal that blinding (constant darkness) has a stimulatory effect whereas CL is inhibitory in the reproduction of the tropical rodent Tatera indica cuvieri. J. Exp. Zool. 289:59-65, 2001.

Animals↗

PubMed2005

Center for the evaluation of risks to human reproduction--the first five years.

The National Toxicology Program (NTP) Center for the Evaluation of Risks to Human Reproduction (NTP-CERHR) was established by the NTP and the National Institute of Environmental Health Sciences (NIEHS) in 1998 to address the impact of chemical exposures on human reproductive and developmental health and to serve as an environmental and reproductive health resource for government agencies and the general public. The purpose of this report is to provide an overview of the Center activities and a summary of NTP conclusions on chemicals evaluated during this time period. CERHR evaluations involve the critical review of reproductive, developmental, and other relevant toxicity data by independent panels of scientists. The products of these evaluations are expert panel reports. The public has opportunities to provide oral comments at the panel meeting and written comments on draft and final expert panel reports. The NTP evaluates these comments, the conclusions of the expert panel, and any new data not available at the time of the panel meeting, and prepares an NTP brief that describes in plain language the NTP's conclusions on the reproductive and developmental hazard from specified chemical exposures. The NTP brief, expert panel report, and public comments comprise the NTP monograph on the chemical. Monographs are sent to federal regulatory agencies, the NTP Executive Committee, and the NTP Board of Scientific Counselors, and are publicly available. Over the last five years, CERHR conducted expert panel evaluations on 14 chemicals. At this time, 13 panel reports have been published and 12 NTP-CERHR monographs have been issued. Additionally, CERHR conducted a 2-day workshop on the role of thyroid hormones in reproductive and developmental health.

Animals↗

PubMed1985

The effects of diet on growth and reproduction in gray short-tailed opossums (Monodelphis domestica).

In order to develop standard conditions for rearing the gray short-tailed opossum, Monodelphis domestica, as a potentially useful experimental laboratory animal, the effects of four different diets on growth and reproduction were assessed. One diet was a meat-based diet prepared in the laboratory. The other three diets were commercially produced fox foods designated Reproduction diet, Lactation diet, and Growing and Furring diet. All pairs of M. domestica fed the Reproduction diet produced at least one litter, but only two-thirds or fewer of the pairs fed any of the other three diets reproduced. There were no significant differences in the number of young born per litter or the number of young weaned per litter among the diets. Weight at weaning was significantly lower for individuals on the meat-based diet compared to those on the fox food diets. Young on the meat-based diet suffered 50% mortality within 6 weeks after weaning, whereas none of the animals fed the fox food diets died within the same 6-week period. Age-weight data were described using the Bertalanffy growth function. In terms of growth and overall reproductive performance, the fox food diets were clearly superior to the meat-based diet, and the Reproduction diet was judged to be the best of the fox food diets tested. Growth curves, from birth to 550 days of age, of individuals fed the Reproduction diet were developed and can be used as standards for the species under laboratory conditions. The maximal weights attained by animals fed the fox food diets were similar to the weights of the wild-caught founders of the laboratory population, indicating that the fox food diets provide adequate nutrition for normal growth. An additional observation was that females housed singly past the normal age of sexual maturity attained significantly lower adult weights than did females that were paired with males at 6 months of age.

Aging↗

PubMed1996

Reproductive toxicity evaluation of methylethyl ketoxime by gavage in CD rats.

Methylethyl ketoxime (CAS No. 96-29-7; MEKO; 2-butanone oxime), an antioxidant agent used in paints, resins, and adhesives, was tested for reproductive toxicity in a two-generation study with CD (Sprague-Dawley) rats. Thirty-eight-week-old rats/sex/group (F0) were administered MEKO in water, by gavage, at 0, 10, 100, or 200 mg/kg/day (at a dosing volume of 2 ml/kg), 5 days/week for 10 weeks with vaginal cytology evaluation (VCE) of F0 females during the last 3 weeks of the prebreed period. Animals were mated within groups for 3 weeks with dosing during mating, gestation, and lactation for 7 days/week. F0 parents and F1 weanlings, 10/sex/dose, were necropsied (after a 2-week postwean VCE in F0 females) with hematologic evaluation (including methemoglobin) and histology of adult livers, spleens, and reproductive organs. F1 weanlings, 30/sex/dose, were dosed for 11 weeks and mated as described above. Because of poor reproductive performance, not treatment related, F1 animals with no F2a litters were rebred to produce F2b litters. F1 parents and F2a weanlings, 10/sex/dose, were necropsied and evaluated as described above. Inguinal mammary glands were examined histologically from all nonselected F1 and F2 (a and b) female weanlings. Adult toxicity was observed in both generations and both sexes at all doses. Treatment-related parental deaths occurred at 200 mg/kg/day. At 100 and 200 mg/kg/day, parents exhibited dose-related reduced body weights and weight gains, reduced feed consumption, clinical signs of toxicity, and anemia with concomitant extramedullary hematopoiesis and hemosiderosis in livers and spleens (and increased spleen weights). At 10 mg/kg/day, only adult liver and spleen histologic effects were present. There was no evidence of reproductive organ or mammary glad pathology or of reproductive or postnatal toxicity at any dose tested. There was no adult "no observable adverse effect level" (NOAEL) established; the NOAEL for reproductive and postnatal toxicity was at least 200 mg/kg/day for rats in this study.

Anemia↗

PubMed2002

Fat is sexy for females but not males: the influence of body reserves on reproduction in snakes (Vipera aspis).

Reproduction is energetically expensive for both sexes, but the magnitude of expenditure and its relationship to reproductive success differ fundamentally between males and females. Males allocate relatively little to gamete production and, thus, can reproduce successfully with only minor energy investment. In contrast, females of many species experience high fecundity-independent costs of reproduction (such as migration to nesting sites), so they need to amass substantial energy reserves before initiating reproductive activity. Thus, we expect that the relationship between energy reserves and the intensity of reproductive behavior involves a threshold effect in females, but a gradual (or no) effect in males. We tested this prediction using captive vipers (Vipera aspis), dividing both males and females into groups of high versus low body condition. Snakes from each group were placed together and observed for reproductive behavior; sex-steroid levels were also measured. As predicted, females in below-average body condition had very low estradiol levels and did not show sexual receptivity, whereas males of all body condition indices had significant testosterone levels and displayed active courtship. Testosterone levels and courtship intensity increased gradually (i.e., no step function) with body condition in males, but high estradiol levels and sexual receptivity were seen only in females with body reserves above a critical threshold.

Adipose Tissue↗

PubMed2000

A review of the developmental and reproductive toxicity of styrene.

The reproductive and developmental toxicity of styrene has been studied in animals and humans. The animal studies on styrene have diverse study designs and conclusions. Developmental or reproductive toxicity studies have been conducted in rats, mice, rabbits, and hamsters. In most cases, high doses are required to elicit effects, and the effects are not unique to reproduction or development. In a number of the reports, either the experimental designs are limited or the descriptions of the designs and the endpoints measured are insufficient to draw conclusions about the toxicity of styrene. The more complete and better-reported studies show that styrene does not cause developmental toxicity at dose levels that are not maternally toxic. Some neurochemical or neurobehavioral effects have been reported at high exposures. Styrene does not affect fertility or reproductive function. Considerable animal toxicity data on styrene support the conclusion that styrene is neither an endocrine-active substance nor an endocrine disrupter. Human studies often suffer from either inadequate exposure data or exposure to a wide variety of materials, so that attribution of effects to styrene exposure is impossible. Furthermore, investigators often have failed to account for other exposures in the workplace or for other potentially confounding factors in their studies. Menstrual cycle irregularities and congenital abnormalities were initially reported; however, the better and more recent reports do not show that styrene causes developmental or reproductive effects in humans. Human studies also support the conclusion that styrene is not an endocrine disrupter. Although some study authors have concluded that styrene is either a human or an animal reproductive or developmental toxicant, careful review demonstrates that such conclusions are not justified.

Abnormalities, Drug-Induced↗

PubMed1990

Photoperiodic requirements for timing onset and duration of the breeding season of the ewe: synchronization of an endogenous rhythm of reproduction.

A study was conducted to test the hypothesis that different portions of the annual photoperiodic cycle play different roles in timing the breeding season of the ewe, Ovis aries, an animal in which an endogenous rhythm generates the seasonal reproductive transitions. Adult female sheep were pinealectomized to disrupt transduction of photoperiodic cues at 4 times of the year (summer and winter solstices, vernal and autumnal equinoxes), and the effects on seasonal reproductive neuroendocrine activity were evaluated. Time of pinealectomy greatly influenced the subsequent seasonal reproductive cycle such that the following inferences are possible. Lengthening days between the winter and summer solstices synchronize reproductive onset to the appropriate time of year. The relatively long days around the summer solstice act to suppress reproductive activity and forestall the start of the breeding season until late summer/early autumn. The shortening days between the summer solstice and autumnal equinox maintain a normal intensity and duration of reproductive neuroendocrine induction during the impending breeding season. However, the shortening days between the autumnal equinox and winter solstice (i.e., after breeding season onset) do not appear to play a critical role in maintaining the breeding season of that year, but may provide important cues for timing the breeding season of the following year.

Animals↗

PubMed1986

Effects of cold, short day and melatonin on thermogenesis, body weight and reproductive organs in Alaskan red-backed voles.

This study examined whether cold, short day or melatonin causes reproductive regression and stimulates nonshivering thermogenesis in a subarctic rodent Clethrionomys rutilus. Red-backed voles born and raised at 23 degrees C and 22 h light per day (LD 22:2) at Fairbanks, Alaska (65 degrees N) were exposed in one of six groups to: 1) long day (LD 22:2), 23 degrees C, injected daily with melatonin or saline 2 h before lights out, 2) long day, 3 degrees C, injected daily with melatonin or saline, 3) short day (LD 8:16), 23 degrees C or 3 degrees C. Voles were tested for nonshivering thermogenesis (NST) prior to and after 8 wk exposure. Body weight, testes weight and female reproductive tract weight were assessed after 8 wk in long day and 12 wk in short day. NST was not altered by short day or melatonin but cold (3 degrees C) caused an increase in NST which was similar in long day and short day. Body weight of males and females was not affected by short day but was decreased by melatonin. Short day did not alter mean testes weight (about 20% voles regressed) but reduced mean female reproductive tract weight (more than 40% voles regressed). Melatonin reduced testes weight and female reproductive tract weight (more than 50% of voles of both sexes regressed). The results suggest that in northern red-backed voles: the pineal does not mediate seasonal changes in thermogenic capacity, the pineal may mediate reduction of body weight and regression of reproductive organs but, in addition to day-length, other cues or factors may be important, populations may exhibit variability in sensitivity of reproduction to photoperiod which could allow for opportunistic breeding.

Animals↗

PubMed1994

Associations of esterase 6 allozyme and activity variation with reproductive fitness in Drosophila melanogaster.

Previous studies have shown that the esterase 6 (EST6) enzyme of D. melanogaster is mainly produced in the sperm ejaculatory duct of the adult male and comparisons of wild-type males with laboratory null mutants have suggested that the enzyme plays a role in reproductive fitness. In this study we have compared 18 field-derived lines each isoallelic for Est6 for differences in five components of male reproductive fitness. No consistent fitness differences were found among lines differing in respect of the two major allozyme classes EST6-F and EST6-S, despite other evidence that these two classes are not selectively equivalent in the field. However, differences in reproductive fitness were found among lines differing in the minor mobility variants that segregate within EST6-F and EST6-S. A failure to distinguish among these minor forms may explain the discrepancies in previous studies on the effects of the major EST6 allozymes on reproductive fitness. The most significant associations we have found between EST6 and reproductive fitness were due to variation in EST6 activity levels. Male EST6 activity levels were found to be positively correlated with their time to first mating, negatively correlated with the numbers of eggs laid and progeny produced by their mates, and negatively correlated with the frequency with which their mates remate. We conclude that some EST6 variants differ in components of male reproductive fitness operative in laboratory cultures. However, the evidence for fitness differences is stronger for variants affecting the amount, rather than the structure of the enzyme, and the direction of the differences varies between some of the fitness components tested.

Alleles↗

PubMedDate not supplied

Women's reproductive health--challenges for the 1990s.

Health policy makers, program planners and donor agencies have paid little attention to issues surrounding women's reproductive health. This paper will look at reproductive health issues surrounding pregnancy and childbirth, the accessibility and safety of contraception, and reproductive tract infections. The gross social injustice caused by high maternal mortality can no longer be ignored. Nor can we ignore the much larger numbers of women who suffer life-long health impairment resulting directly from the health hazards associated with pregnancy and childbirth. The challenge is to reduce maternal mortality by at least 50% by the year 2000. If these challenges are not faced, the 1990s may very well be remembered as the decade that saw the largest numbers of women dying in childbirth and pregnancy. The 1990s will see the addition of some 300 million couples to the reproductive age group. These couples will need access to good sexual health care, including safe and effective contraception, and prevention of reproductive tract infections and sexually transmitted disease. The biomedical consequences of reproductive tract infections are, among others, fetal wastage, low birth weight, carcinoma of the cervix, infertility and ectopic pregnancy. In addition to these consequences, there are the psychological, social and economic costs of these diseases. Some suggestions for meeting these challenges are put forward. These include building on existing programs and expanding available resources to help women to attain health, dignity, and their basic human rights.

Female↗