Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “REPRODUCTION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

[Effects of a comprehensive health education program on reproductive tract infections/sexually transmitted diseases intervention among reproductive age population in the rural areas of China].

OBJECTIVE: To evaluate the effectiveness on comprehensive health education intervention program regarding reproductive tract infections/sexually transmitted diseases (RTIs/STDs) among reproductive age population in the rural areas of China. METHODS: Data were generated from the Reproductive Health/Family Planning Project implemented by the State Family Planning Committee and the Ministry of Health from 1998 to 2002, which covered 32 counties in 22 provinces. A quasi-experimental design was used. Six counties were selected from 32 project counties as intervention group, while 6 non-project counties were taken as controls which were similar in number of population and economic level to the counties as selected. Subjects of the study were mothers with children under 3 years and men under 35 years of age. A total number of 675 mothers and men were interviewed using a structured questionnaire by strictly trained investigators. Logistic model was used to compare the difference of knowledge on RTIs/STDs between intervention group and control group. OR value was used to describe the degree of the difference. RESULTS: Over the 18 month intervention period, persons in the intervention group had more knowledge of RTIs/STDs than those in control group. Logistic regression analysis indicated that intervention was significantly associated with better knowledge on factors as transmission, risks, symptoms, management and prevention of RTIs/STDs with 95% CI of OR as 2.4 - 6.4, 2.0 - 4.8, 3.0 - 6.4, 1.9 - 5.7 and 1.8 - 6.8 respectively, after controlling the demographic factors. Level of education was an important factor influencing the subjects to receive knowledge on RTIs/STDs. CONCLUSION: Comprehensive health education intervention programs had significant impact on knowledge about RTIs/STDs among the target population, indicating that the Reproductive Health/Family Planning Project implemented in the rural areas of China had been successful.

Adult↗

[Mexico: reproductive behavior and social margination, 1970-1990. Elements of geographic diagnosis in reproductive health].

The lack of a definite knowledge on regional reproductive behavior characteristics hinders the evaluation of the goals stated in the General Population Law (Ley General de Población) and counteracts any efforts towards equating population growth with regional development. The present work aims at overcoming this problem. Indirect specific fertility rates and global fertility rates (GFR) were obtained by state, using census and vital statistics data for the states of Mexico during the 1970-1990 period. Reproductive behavior was related to social deprivation indexes used by PRONASOL and CONAPO for those years. A high statistically significant correlation (p < 0.01) between state social deprivation levels and the downward trends of GFR for the same decades was found. Findings evidence a general downward trend of GFR during the period of study. However, this trend was not uniform across the country. Further studies are needed to determine whether these differences are due to the various social deprivation levels rather than to the effectiveness and extension of family planning programs. Mapping these results could be useful as diagnostic elements of the reproductive behavior of the population and also generates information necessary to support social organized responses in reproductive health.

Adult↗

Recurrent reproductive failure associated with porcine reproductive and respiratory syndrome in a swine herd.

An investigation of a case of recurrent reproductive failure in a swine herd was conducted. The subject farm (A) and a neighboring farm (B) had experienced an acute outbreak of porcine reproductive and respiratory syndrome in 1990. During 1992, farm A experienced recurrent episodes of conception failure, stillbirths, preweaning mortality, and sow mortality. Similar clinical findings were not evident on farm B. Evaluation of production records indicated that the problem was occurring in first-parity litters. It was learned that replacement gilts for farm A were being purchased from an outside source, whereas farm B raised its own replacement gilts. Indirect fluorescent antibody testing of gilts from both farms indicated a high prevalence of seronegative gilts on farm A vs a high prevalence of seropositive gilts on farm B. Although there is no correlation between indirect fluorescent antibody titers and immunity, it would appear that exposure to porcine reproductive and respiratory syndrome virus prior to breeding is essential to prevent reproductive disease.

Animals↗

Reproductive biotechnologies: current status in porcine reproduction.

During the past decade, considerable attention has been directed toward the development of reproductive technologies for both research purposes and for more controlled swine reproduction. Artificial insemination is an example of a technology that has continued to be expanded from early use in European countries to the USA and Canada where it is now estimated that a majority of the sows bred are artificially inseminated. In addition, several significant technological advancements have been made in the genetic modification of swine and interest has been generated in the possible use of swine as donors of specific tissues and of organs for the improvement of human health. At the same time, the systems for production of swine for human food continue to undergo major changes including, in some countries, the consolidation of swine into large, integrated units. These swine operations are very receptive to the use of technologies to reduce labor costs as well as a basis for increased production efficiency. Therefore, the combined interest in swine reproductive technologies by both the medical field and the swine industry creates an increased effort for the development of new technologies as well as for the implementation of existing ones. One of the more rapid technological advancements this decade has been the progress in in vitro production (IVP) of swine embryos. Major advancements have been made on the development of procedures for production of large numbers of embryos from oocytes collected at slaughter houses which are then matured (IVM) and fertilized (IVF) in the laboratory. Success in IVP has stimulated increased research in other areas that can be enhanced by the availability of embryos without a requirement for surgical collection from gilts or sows. One example is the combined use of IVF, gender-sorted sperm cells, and embryo transfer to produce offspring of a predicted sex. In a related area, instrumentation for non-surgical embryo transfer has recently been developed that results in significant improvement in this technology. Similar achievements have been gained in cryopreservation of embryos by vitrification. These developments will be reviewed with emphasis on the in vitro production of embryos from immature oocytes.

Animal Husbandry↗

Reproductive rights and reproductive behavior. Clash or convergence of private values and public policies?

Using a rational scientific approach upholding public health values, this article notes experience gained from 25 years of cooperative transnational research on reproductive behavior. An overview of world population trends is followed by discussions of reproductive rights as a human right, the utility of acceptability studies of modern methods of fertility regulation, and findings from research on psychological responses to abortion, long-term developmental effects of compulsory pregnancy, and the use of incentives and disincentives to influence family size. There is also consideration of the clash between private values and public policy on reproductive behavior in the United States and the convergence achieved in Denmark and the Netherlands, where rates of unintended pregnancy are among the world's lowest.

Abortion, Legal↗

New reproductive technologies: Equity and access to reproductive health care.

While attention has focused on the promise of new reproductive technologies to provide cures for infertility, efforts aimed at preventing infertility have languished, and the major cause of infant morbidity and morality--lack of prenatal care--has worsened. This article explores the social and ethical issues arising out of the uses of three new reproductive technologies: surrogacy, in vitro fertilization, and prenatal screening. In addition, coerced medical interventions during pregnancy are described. Examination of the social circumstances surrounding the use of these medical technologies supports the conclusion that new reproductive technologies have increased, rather than decreased, inequities in access to and allocation of health care resources.

Coercion↗

Reproductive and therapeutic cloning, germline therapy, and purchase of gametes and embryos: comments on Canadian legislation governing reproduction technologies.

In Canada, the Assisted Human Reproduction Act received royal assent on 29 March 2004. The approach proposed by the federal government responds to Canadians' strong desire for an enforceable legislative framework in the field of reproduction technologies through criminal law. As a result of the widening gap between the rapid pace of technological change and governing legislation, a distinct need was perceived to create a regulatory framework to guide decisions regarding reproductive technologies. In this article the three main topics covered in the new legislation are commented on: cloning, germline therapy, and purchase of gametes and embryos. Some important issues also covered in the new legislation, such as privacy and access to information, data protection, identity of donors, and inspection, will not be addressed.

Canada↗

Assisted reproductive technologies in europe encompass diverse and complex ethical viewpoints: issues to be considered in reporting research in human reproduction.

The many dimensions of the field of reproduction (clinical, scientific, social, ethical, legal) must be addressed by those with editorial responsibility for the major journals in the field. As the editorial team of the leading reproductive journal Human Reproduction, we have evolved processes that attempt to ensure a transparent but robust approach to complexities whose impact varies across international boundaries.

Cloning, Organism↗

Fitness and extra-group reproduction in male Verreaux's sifaka: An analysis of reproductive success from 1989-1999.

Adult males in social groups often compete with other male group members for access to adult females. In some primate species, males also seek mating opportunities in neighboring social groups. Such extra-group fertilizations (EGFs) provide an additional source of variation in male fitness. This additional component of fitness provided by EGFs must be incorporated into analyses that investigate sources of variation in male lifetime reproductive success. In this study, a model is analyzed in which male fitness over a 10-year sample period is decomposed into additive and multiplicative variance and covariance components. The data come from an ongoing study of a wild population of Verreaux's sifaka (Propithecus verreauxi verreauxi) located at Beza Mahafaly Special Reserve, Southwest Madagascar. Paternity and demographic data for 134 males are used to decompose male fitness into the following three multiplicative components: reproductive lifespan during sample period, fertility, and offspring survival. These multiplicative components are estimated for males reproducing within their resident groups plus (i.e., the additive portion) for males reproducing in neighboring social groups. The analysis shows that variation in fertility makes the largest contribution to variation in total fitness, followed by variation in amount of time spent in sample period (which is a proxy of total reproductive lifespan) and variation in offspring survival. EGFs contribute an important source of variation to male fitness, and numerous factors enhance the opportunities for EGFs in male sifaka. These include female choice, a high degree of home range overlap, and a limited mating season.

Animals↗

Reproduction rate and viability of Merino, Nilagiri and halfbred Merino. II. Age specific replacement rate and net reproduction rate.

Age specific replacement rate, net reproduction rate and intrinsic rate of population increase were estimated from records over a period of 11 years of Merino, Nilagiri and halfbreds. On an average for every 1000 ewes mated 830 ewes lambed, 917 lambs were born, 898 lambs were weaned and 422 ewe lambs survived to joining age (one and a half years) in Nilagiri sheep. The corresponding figures were 665, 685, 590 and 228 in Merino and 664, 709, 691 and 341 in halfbreds. Nilagiri ewes in intermediate ages had more multiple births and older ewes weaned more lambs. The flock strength was not maintained unless the ewes were kept till the fifth lambing in Merino, third lambing in Nilagiri and fourth lambing in halfbred Merino. These results along with the culling levels indicated that the low reproductive efficiency in halfbreds may not be critical enough to avoid introduction of Merino for improvement in productivity. However, the poor reproductive efficiency of the Merino in this country may necessitate repeat importations of Merino rams for production of halfbreds.

Age Factors↗

Reproductive ectogenesis: the third era of human reproduction and some moral consequences.

In a well known story Derek Parfit describes a disconnection between two entities that normally (in real life) travel together through space and time, namely your personal identity consisting of both mind and body. Realising the possibility of separation, even if it might never happen in real life, new questions arise that cast doubt on old solutions. In human reproduction, in real life, at present the fetus spends approximately nine months inside the pregnant woman. But, we might envisage other possibilities. Historically, the first era is the normal conception inside the woman, the growth of the fetus in the womb and then, after nine months, birth and the appearance of a new individual. The second era is In Vitro Fertilisation (IVF). The fetus starts outside the woman as a fertilised egg, moves to the body of the woman and spends nine month there, where the body of the woman and the fetus travel together in space-time to separate at birth. In the third era of reproductive ectogenesis, the two never travel together. The fetus spends its gestational time entirely outside the woman's body. We have two entities separated in space-time the whole time. The intimate connection consisting in the fetus being a part of the woman's body is gone. In this paper I will briefly comment on the three eras of human reproduction--and primarily on the relationship between the new individual and the woman--and then spend some time with a fictional story illustrating some moral consequences of the third era. The story is from Pig Pharmaceuticals Limited and how they in the year 2050 report the successful development of pig-related pregnancies with transgenic pigs as surrogate mothers.

Animals↗

Identification and assessment of the effects of chemicals on reproduction and development (reproductive toxicology).

Most studies for determining the reproductive toxicity of a chemical have to be conducted with whole animals. Test procedures used to investigate parts or the whole of the reproductive cycle are described in current guidelines. Other techniques, such as in vitro methods, and those for investigating specific events in the cycle, are under development. Epidemiological studies can give valuable information, although they are difficult to perform and interpret in practice. There is a need for more epidemiological studies of exposed populations and for recording and quantifying the concentrations of chemicals to which such populations are exposed. It is suggested that animal experiments should be programmed in a stepwise manner, and should take into account effects seen in previous toxicity studies. The programme of tests for determining reproductive toxic potential should be established on a case-by-case basis, since many factors will influence the choice of studies and the sequence in which they should be performed.

Animals↗

Seroprevalence of six reproductive pathogens in European wild boar (Sus scrofa) from Spain: the effect on wild boar female reproductive performance.

We studied the seroprevalence of six reproductive pathogens in Spanish hunter-harvested wild boar females. The sample was representative of the hunting harvest in the studied hunting estates. Mean antibody prevalences were: 60.6+/-0.06% for Aujeszky's disease virus (ADV), 56.6+/-0.09% for porcine parvovirus (PPV), 51.8+/-0.06% for porcine circovirus type 2 (PCV2), 29.7+/-0.09% for Brucella spp. and 36.3+/-0.1% for Toxoplasma gondii. We did not detect antibodies against porcine reproductive and respiratory syndrome virus (PRRSv). ADV seroprevalence was associated with PPV and PCV2 seroprevalence in Spanish wild boar females. Ovulation rate in the studied wild boar females was 4.41+/-0.16 (n=120), mean litter size was 3.91+/-0.16 (n=82) and the partial resorption index 0.92+/-0.17 (n=66). Ovulation rate and litter size were statistically associated with age. T. gondii seroprevalence was negatively related to ovulation rate and partial resorption index. Wild boars from managed fenced estates had antibodies against more pathogens than wild boars from open estates. Potential relations between management of wild boar populations and exposure of individuals to different reproductive pathogens are discussed.

Aging↗

Reproductive immunology update: the 52nd annual meeting of the American Society of Reproductive Medicine.

The American Society of Reproductive Medicine meeting (formerly the American Fertility Society) was held in Boston, Massachusetts, USA, on November 2-6, 1996. Numerous abstracts concerning original research in reproductive immunology were presented at the meeting. In addition, seminars and round table discussions were held on the topics of hormonal immunocontraception, immunologic testing in reproduction, antiphospholipid syndrome, endometriosis, and immunologic infertility.

Allergy and Immunology↗

Prior experience with photostimulation enhances photo-induced reproductive development in female European starlings: a possible basis for the age-related increase in avian reproductive performance.

Reproductive performance in female birds improves with age, and this is generally attributed to experiences obtained during breeding. In temperate-zone species, experience with photostimulation during the first breeding year may prime the hypothalamo-pituitary-gonadal axis to respond to photic cues more rapidly or robustly in subsequent years. To test this idea, we captured 32 photorefractory juvenile (hence naive to photostimulation) female European starlings (Sturnus vulgaris) and held half of them (naive group) on a photoperiod of 8L:16D for 32 wk and the other half (experienced group) on 8L:16D for 12 wk, 16L:8D for 12 wk, and then 8L:16D for 8 wk. When we subsequently transferred all birds to 16L:8D, the increase in body mass, which may presage egg laying in the wild, was more robust in experienced than in naive females. Experienced females also showed a more robust elevation in plasma concentrations of the yolk-precursor protein vitellogenin, although naive females showed an initial rapid but transient rise in vitellogenin that we attribute to their extended exposure to short-day photoperiods prior to photostimulation. Finally, the photo-induced increase in diameter of the largest ovarian follicle, in plasma concentrations of luteinizing hormone, and in the number of septo-preoptic fibers relative to the number of cell bodies immunoreactive to GnRH was greater in experienced than in naive females. Thus, prior experience with photostimulation enhances some initial phases of photo-induced reproductive development and may explain, in part, why reproductive performance improves with age in temperate-zone birds.

Aging↗

Disruption of the tissue inhibitor of metalloproteinase-1 gene results in altered reproductive cyclicity and uterine morphology in reproductive-age female mice.

Tissue inhibitor of metalloproteinase-1 (TIMP-1) is a multifunctional protein expressed in the uterus of essentially all species, yet the function of this protein is uncertain. To assess the role of TIMP-1 in the uterine events that occur during the murine estrous cycle, mature female TIMP-1 wild-type and null mice were monitored for reproductive cyclicity. Mice were sacrificed in each stage of the estrous cycle, and peripheral blood was collected and assayed for serum estradiol and progesterone content by RIA. Uterine morphology and TIMP-1, TIMP-2, TIMP-3, and TIMP-4 mRNA expression were also examined between genotypes in each stage of the estrous cycle. Disruption of the TIMP-1 gene product was associated with an altered reproductive cycle characterized by a significant decrease in the length of the estrus period in the null mice. Also during the period of estrus, null mice expressed significantly lower levels of uterine TIMP-3 mRNA expression, altered uterine morphology, significantly higher serum estradiol levels, and significantly lower serum progesterone levels compared to their wild-type counterparts. It is concluded from this study that TIMP-1 has a multifaceted role in regulating the murine reproductive cycle, and this control appears to be at the level of both the uterus and the ovary.

Animals↗

Reproduction in the space environment: Part I. Animal reproductive studies.

Mankind's exploration and colonization of the frontier of space will ultimately depend on men's and women's ability to live, work, and reproduce in the space environment. This paper reviews animal studies, from microorganisms to mammals, done in space or under space-simulated conditions, which identify some of the key areas which might interfere with human reproductive physiology and/or embryonic development. Those space environmental factors which impacted almost all species included: microgravity, artificial gravity, radiation, and closed life support systems. These factors may act independently and in combination to produce their effects. To date, there have been no studies which have looked at the entire process of reproduction in any animal species. This type of investigation will be critical in understanding and preventing the problems which will affect human reproduction. Part II will discuss these problems directly as they relate to human physiology.

Animals↗

Reproduction in the space environment: Part II. Concerns for human reproduction.

Long-duration space flight and eventual colonization of our solar system will require successful control of reproductive function and a thorough understanding of factors unique to space flight and their impact on gynecologic and obstetric parameters. Part II of this paper examines the specific environmental factors associated with space flight and the implications for human reproduction. Space environmental hazards discussed include radiation, alteration in atmospheric pressure and breathing gas partial pressures, prolonged toxicological exposure, and microgravity. The effects of countermeasures necessary to reduce cardiovascular deconditioning, calcium loss, muscle wasting, and neurovestibular problems are also considered. In addition, the impact of microgravity on male fertility and gamete quality is explored. Due to current constraints, human pregnancy is now contraindicated for space flight. However, a program to explore effective countermeasures to current constraints and develop the required health care delivery capability for extended-duration space flight is suggested. A program of Earth- and space-based research to provide further answers to reproductive questions is suggested.

Extraterrestrial Environment↗