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PubMed2003

Immunization of pregnant women: reproductive, medical and societal risks.

Establishing successful vaccine programs for pregnant women would be the quintessence of preventive medicine when you realize the preventive potential for reproductive problems of many of the new and old vaccines. The development of vaccines to prevent maternal, fetal and newborn disease is actually in its infancy. The risks and benefits are discussed in detail as well as the most appropriate and inappropriate time to immunize women of reproductive age and pregnant women. The great majority of risks are theoretical, but the problem is that birth defects and other developmental and reproductive problems are in the group of "diseases of affliction" which means that there are tremendous emotional upheavals in families affected with serious reproductive problems. The failures in reproduction are so common that immunization of a pregnant women has potential deleterious consequences. A consortium of government, academia and industry must work together and an appeal to the more responsible members of the law profession to solve the problem of non-meritorious litigation has be in place before manufacturers of vaccines will be willing to initiate the development of new vaccines. The potential for reducing the incidence of birth defects, prematurity and neonatal infectious disease exists, but it will be difficult to initiate these programs because vaccine makers may be unwilling to assume an additional burden of negligence litigation. Certainly, it is clear that we could provide a safe vaccine for Group B streptococcus and infant botulism that would be of immediate benefit and the potential for reducing other diseases is realistic. This is not going to be an easy task.

Adult↗
PubMed1999

Inhibition of reproductive growth of Arabidopsis in airtight vessels.

Airtight vessels have various advantages for space experiments. However, Arabidopsis thaliana plants scarcely produced seeds when grown in such vessels. The mechanism by which reproductive growth is inhibited in airtight vessels was studied. The length of the flower stalk was shorter when the plants were grown in airtight vessels. Thus, there was a possibility that the inhibition of reproductive growth was due to the inhibition of vegetative growth. However, even when the plants which has grown under non-airtight conditions and has reached to the flowering stage were transferred to airtight vessels, silique formation was inhibited, suggesting that the airtight environment directly influences reproductive growth. In airtight vessels, anther dehiscence was inhibited, which appears to be the cause of inhibition of silique formation and seed development. Reproductive growth recovered when silica gel was added to the vessels. These results suggest that in airtight vessels, high humidity causes a suppression of anther dehiscence, resulting in the inhibition of reproductive growth. Therefore, the control of humidity by ventilation should be taken into consideration in designing a growth chamber for space experiments.

Arabidopsis↗
PubMed2002

Researching sexual and reproductive behaviour: a peer ethnographic approach.

In recent years, ethnographic research has challenged the notion within demography that fertility-related behaviour is the outcome of individualistic calculations of the costs and benefits of having children. Anthropology has further criticised the abstraction in demographic analysis of sexual behaviour and fertility decision-making from the socio-cultural and political context in which the individual or couple is located. Within demography itself, institutional and political-economic analyses have argued strongly that sexual and reproductive behaviour must be understood within locally specific social, cultural, economic and political contexts. Positivist and empiricist research methods, such as the sample survey and focus groups, which continue to dominate demographic inquiry and applied research into sexual and reproductive behaviour, have been shown to be limited in their ability to inform about the process of behaviour change and contexts within which different behaviours occur. The article introduces a new methodology for researching sexual and reproductive behaviour, called the peer ethnographic approach, which the authors have developed in an attempt to address some of the limitations of the methods which currently dominate research into sexual and reproductive behaviour. The peer ethnographic methodology is discussed in detail and the results of recent field-testing are reported, which show that, although the approach has limitations, it also has the potential to make a significant contribution to our understanding of sexual and reproductive behaviour.

Adolescent↗
PubMed1999

Study of preantral follicle population in situ and after mechanical isolation from caprine ovaries at different reproductive stages.

The purposes of this study were to estimate the population of caprine preantral follicles, and to evaluate quantitatively and qualitatively the efficiency of a specific mechanical method for the isolation of preantral follicles from mixed breed goats at different reproductive stages. On average, 37,646+/-4277 preantral follicles were present in goat ovaries, and 13,631+/-2399 preantral follicles were obtained after isolation. The number of preantral follicles isolated or in situ was not significantly affected by the reproductive stage. The mean recovery rate per ovary ([number of isolated follicles/number of in situ follicles] x 100) of isolated follicles was 36.2%. The distribution of follicles in situ was 67.8% primordial, 25.8% primary and 6.4% secondary; the respective distribution after isolation was 93.8%, 5.2% and 1.0%. In this study, many polyovular follicles were also observed, mainly in prepubertal goat ovaries. Histological analysis showed that few preantral follicles were atretic in situ (4.83%+/-0.35) or after the isolation procedure (4.67%+/-0.65) in the three reproductive stages. The percentage of atretic follicles was not affected either by the mechanical method or by the reproductive stage. It is concluded that a large number of preantral follicles can be successfully isolated mechanically, with a high recovery rate and a low rate of follicular atresia, irrespective of the reproductive stage of the caprine female.

Age Factors↗
PubMed2000

Analysis of menstrual diary data across the reproductive life span applicability of the bipartite model approach and the importance of within-woman variance.

The nature of variability in menstrual function has not been adequately described or quantified across the reproductive life span. This article evaluates the applicability of the bipartite model approach to the analysis of menstrual data and the relative importance of within-woman variability across the reproductive life span using data from the Tremin Trust data, a large prospective study in which women maintained menstrual diaries throughout their reproductive life. We first consider how the boundaries of the Gaussian portion of the distribution change with age, and reflect upon the implications of these distribution changes for definitions of normal cycling. We next estimate the change in mean cycle length, in between- and within-woman variance and in the probability of having a nonstandard cycle across the reproductive life span. Finally, we characterize the dynamics of menstrual cycling within women over time at various points in the reproductive life span.

Adolescent↗
PubMed2004

Morphology of the male reproductive duct system of Caiman crocodilus (Crocodylia, Alligatoridae).

The male reproductive duct system of Caiman crocodilus in different reproductive stages was studied using light and electron microscopy, to determine whether shared morphological features exist between Crocodylia and Aves, in concurrence with the Archosauria hypothesis. The sexual duct system of Caiman crocodilus is constituted of the rete testis, ductuli efferentes, ductuli epididymides, ductus epididymidis, and ductus deferens. The morphology and histochemical properties of these ducts suggest their involvement in seminal fluid production and/or its modification. Three types of non-ciliated cells were identified along the duct system. 1. The noncliated cells of the ductuli efferentes contain electron dense worm-like structures and coated vesicles, both related to absorptive processes, as has been suggested in Aves. 2. The non-ciliated cells of the ductuli epididymides have apical electron dense granules suggesting a secretory role, and 3. The non-ciliated cells of the ductus epididymidis and ductus deferens did not exhibit conspicuous storage of secretory material, but have a prominent rough endoplasmic reticulum content indicating active protein production. The occurrence of abundant secretory granules in the epithelial cells of the distal ductus deferens during non-reproductive stages suggests its participation in the removal of luminal debris when the reproductive season ends. Additional ducts were observed running along the ductus deferens; they shared morphological characteristics with the ductuli epididymides. The maximum diameter and therefore the greatest sperm accumulation of the excurrent ducts were observed during the initial testicular regression. The comparative analysis suggests that the male reproductive system of the Crocodylia exhibits structural characteristics nearer to those of Aves than to Lepidosauria, Testudines, and Mammalia, additional data that support an Aves and Crocodylia sister group relationship.

Alligators and Crocodiles↗
PubMed2003

Parental presence and adolescent reproductive health among the Nairobi urban poor.

PURPOSE: To investigate whether the presence of parents constitute a protective factor against adverse reproductive health outcomes for adolescents living in slums of Nairobi, Kenya. METHODS: The data come from a cross-sectional survey that canvassed a random sample of 4564 households representative of all Nairobi slums in February-June 2000. Structured questionnaires on household census, reproduction and adolescent health were verbally administered to household heads, women of reproductive ages, and adolescents, respectively. We restrict the analysis to a sub-sample of 788 never-married adolescent girls aged 12-19 years. We compare reproductive health outcomes of adolescents who live with neither parent, father only, mother only, and both parents. Data were analyzed using simple descriptive analysis and logistic regression models of three outcome variables: ever sexually active, ever experienced an unplanned pregnancy, and sexually active within the past 4 weeks. For each of the outcome variables, two models, one with and one without a proxy for adolescents' disorderly behavior are presented to establish whether parental presence affects adolescents' reproductive health. RESULTS: When the father is present in the household (i.e., father only or both parents present), adolescent girls are 42% less likely to have ever had sex (p<.05), 45% less likely to have been sexually active in the most recent 4-week period (p<0.1), and 59% less likely to have ever experienced an unwanted pregnancy (p<.05) than when neither parent, or only the mother, is present in the household. CONCLUSIONS: In the slums of Nairobi, father's presence, unlike that of the mother, is associated with stronger resilience among adolescents. When programming for adolescents in these resource-constrained settings, it is important, therefore, to involve parents.

Adolescent↗
PubMed2000

Surgery of the avian reproductive and gastrointestinal systems.

Surgery of the female reproductive system is the most commonly indicated intra-abdominal surgery of avian patients. Surgery of the male reproductive system and avian gastrointestinal tract are less commonly indicated but are occasionally necessary. Indications for surgery of the female reproductive tract include egg-laying-related disorders, dystocia, egg binding, damage or trauma to the oviduct, oviductal torsion and volvulus, abnormal egg production, biopsy or culture of the oviduct, internal laying, egg related coelomitis, oviductal impaction, oviductal or ovarian neoplasia, ovarian cysts, or as a sterilization procedure to stop egg laying. Indications for surgery of the male reproductive tract include castration (most often as a treatment of behavioral problems) and treatment of testicular neoplasia. Indications for gastrointestinal tract surgery include repair of traumatic injury, foreign-body retrieval, obstructive disease, as a treatment for neoplasia, and as a diagnostic tool to retrieve tissue for biopsy. Avian reproductive anatomy and physiology are reviewed. Presurgical and postsurgical patient care ensures successful recovery. Lateral, horizontal, and midline approaches may be preferred based on indication or concurrent disease. Approaches are described in detail. Indications and descriptions of surgery conclude this article.

Animals↗
PubMed2003

Effects of dietary methylmercury on reproductive endocrinology of fathead minnows.

Recent laboratory studies have demonstrated that environmentally realistic concentrations of dietary methylmercury can impair reproduction of fish. To evaluate relations between reproductive success and biomarkers of methylmercury exposure, we fed juvenile fathead minnows (Pimephales promelas) one of three diets contaminated with methylmercury: 0.06 (control), 0.87 (low), and 3.93 (medium) microg of Hg g(-1) dry weight. At sexual maturity, fish were paired, allowed to reproduce, and then analyzed for total mercury, plasma testosterone (T), and 17beta-estradiol (E2). Diets did not affect survival or growth of fathead minnows. Methylmercury suppressed levels of T in males and E2 in females. Male fathead minnows fed the control diet had mean T concentrations 20% and 106% greater than those fed the low and medium diets; control females had mean E2 concentrations 149% and 402% greater than those fed the low and medium diets. Methylmercury also inhibited gonadal development of females; the gonadosomatic index (GSI) of females fed the medium diet was 40% less than that of females fed control or low diets. Plasma levels of T in males and E2 in females were positively related to GSI. Methylmercury reduced the reproductive success of fathead minnows. Spawning success was 32% for pairs fed the control diet, 12% for pairs fed the low diet, and 0% for pairs fed the medium diet. Pairs fed the low diet required, on average, 5 d longer to spawn a clutch of eggs than the controls. Concentrations of methylmercury fed to fathead minnows in this study are also encountered by invertivorous and piscivorous fish in some methylmercury-contaminated aquatic ecosystems. This suggests that reproduction of wild fishes may be adversely affected by methylmercury and that suppressed hormone levels may be used to indicate diminished reproduction of fish.

Administration, Oral↗
PubMed2000

Violence and reproductive health: current knowledge and future research directions.

OBJECTIVES: Despite the scope of violence against women and its importance for reproductive health, very few scientific data about the relationship between violence and reproductive health issues are available. METHODS: The current knowledge base for several issues specific to violence and reproductive health, including association of violence with pregnancy, pregnancy intention, contraception use, pregnancy terminations, and pregnancy outcomes, are reviewed and suggestions are provided for future research. RESULTS: Despite the limitations of current research and some inconclusive results, the existing research base clearly documents several important points: (1) violence occurs commonly during pregnancy (an estimated 4%-8% of pregnancies): (2) violence is associated with unintended pregnancies and may be related to inconsistent contraceptive use; and (3) the research is inconclusive about the relationship between violence and pregnancy outcomes. CONCLUSIONS: Improved knowledge of the risk factors for violence is critical for effective intervention design and implementation. Four areas that need improvement for development of new research studies examining violence and reproductive-related issues include (1) broadening of study populations, (2) refining data collection methodologies, (3) obtaining additional information about violence and other factors, and (4) developing and evaluating screening and intervention programs. The research and health care communities should act collaboratively to improve our understanding of why violence against women occurs, how it specifically affects reproductive health status, and what prevention strategies may be effective.

Battered Women↗
PubMed2003

Multiple autoantibodies associated with autoimmune reproductive failure.

PURPOSE: Autoimmune factors are involved in some of the cases of reproductive failure. The aim of this paper is to discuss the association between autoantibodies and reproductive failure. METHODS: Literature review of autoantibodies associated with reproductive failure. RESULTS: Several autoantibodies were found in association with such clinical manifestations, mainly in patients having systemic lupus erythematosus or the antiphospholipid syndrome. These autoantibodies include "classical" antiphospholipid antibodies such as anticardiolipin, anti-beta2-glycoprotein-I, antiphosphatidylserine, and antiphosphatidylethanolamine. There are also some "nonclassical" antiphospholipid antibodies directed to prothrombin, thromboplastin, or mitochondrial antibodies of M5 type, which were also found in patients with reproductive failure. Moreover, animal models as well as some human studies support a role for other autoantibodies in these clinical manifestations including antihyroglobulin, antilaminin-1, anti-corpus luteum, antiprolactin, anti-poly(ADP-ribose), and lymphocytotoxic antibodies. CONCLUSIONS: Even though there is not enough data currently to support a firm association between some of these autoantibodies and reproductive failure, future studies are likely to help us determine and expand the number of autoantibodies screened in these patients.

Abortion, Habitual↗
PubMed2002

Living with Marfan syndrome III. Quality of life and reproductive planning.

As individuals with Marfan syndrome are increasingly diagnosed earlier in life and prior to life-threatening cardiovascular events, there is opportunity to study factors that influence their reproductive planning and quality of life. In this study of 174 affected adults, the overall quality of life was reported to be adequate, although it was significantly decreased within the spiritual/psychological domain. Approximately 62% agreed that having Marfan syndrome significantly affected their reproductive decision-making. This view was correlated with age of diagnosis, mitral valve prolapse, and the view that Marfan syndrome has adverse consequences on life. Sixty-nine percent reported personal interest in prenatal testing for Marfan syndrome. Respondents most commonly cited increased worries about personal health and the recurrence risk as ways that Marfan syndrome affects their reproductive decisions. Age, striae, back pain, and low quality of life were each independently correlated with lack of sex drive. These results affirm the importance of both clinical and psychosocial issues on affected adults' reproductive decision-making and sexual well-being. Genetic professionals are ideally positioned to discuss concerns about quality of life and reproduction with patients with Marfan syndrome and refer those with significant concerns for further evaluation and management.

Adolescent↗
PubMed2002

Restricted entry of IgG into male and female rabbit reproductive ducts following immunization with recombinant rabbit PH-20.

PROBLEM: Successful immunocontraception using sperm antigens is dependent on achieving sufficient sperm-specific antibody in the reproductive ducts to prevent fertilization. The blood: luminal barrier of the male and female reproductive ducts must be overcome for this to occur. We have, therefore, investigated the relative titers of antigen-specific immunoglobulin G (IgG) in luminal fluids collected from male and female rabbit reproductive ducts following immunization with recombinant rabbit PH-20 (rPH-20). METHOD OF STUDY: Male and female rabbits were immunized subcutaneously with rPH-20 in Freund's adjuvant. Reproductive tract fluids and plasma were collected and assayed for specific IgG by enzyme-linked immunoabsorbent assay (ELISA). Plasma anti-rPH-20 antibodies were tested for their ability to inhibit in vitro fertilization. RESULTS: Plasma rPH-20-specific IgG titers of > 21 x 106 were induced in bucks. Antibody levels in the rete testis and cauda epididymidis fluids were only 0.026 and 0.168% of plasma levels, respectively. Plasma IgG titers were > 30 x 10(6) in does, but antibody levels in free flow vaginal fluid, free flow uterine fluid and free flow oviduct fluid were only 0.016, 0.078 and 0.072% of plasma levels, respectively. Induction of ovulation by administration of human chorionic gonadotrophin (hCG) significantly increased rPH-20-specific IgG only in free flow vaginal fluids. Plasma antibody from immunized rabbits inhibited in vitro fertilization but conception rates following mating of rPH-20 immunized male to untreated female rabbits were not affected. CONCLUSIONS: The IgG antibody entry into the reproductive ducts of both male and female rabbits is restricted to less than 0.2% of levels induced in plasma following subcutaneous immunization. This finding raises doubts about the suitability of rPH-20 to induce immunocontraception in rabbits using strategies optimized for induction of a serum antibody response. Whether mucosal immunization strategies can achieve this remains to be tested.

Animals↗
PubMed1991

Effect of intrauterine position and social density on age of first reproduction in wild-type female house mice (Mus musculus).

In laboratory strains of mice, reproductive maturation is influenced by both the fetal and the peripubertal social environments experienced by females. Intrauterine position (IUP) for female fetuses is identified by the number of adjacent males; where 0M have zero, 1M have one, and 2M have two male neighbors. We sought to confirm, using wild-type female house mice (Mus musculus), the previous finding in the CF-1 strain of laboratory mouse that males prefer 0M over 2M females as mates. We recorded the age at first reproduction for females of known IUP housed either individually with a male or in a group of 6 females and a male. In neither housing condition were there significant differences in age of first reproduction among females of different IUPs, but 0M females that were group housed had perforate vaginas at an earlier age than other group-housed females. Mean (+/- SE) age at first reproduction was 58.1 (+/- 3.3) for paired and 126.6 (+/- 5.1) for group-housed females. The reproductive suppression observed in the grouped females was probably due to the interaction of inhibitory urinary chemosignals, low body weights, and female dominance hierarchies.

Animals↗
PubMed1985

Lower prevalence of breast cancer and cancers of the reproductive system among former college athletes compared to non-athletes.

The prevalence (lifetime occurrence) rate of cancers of the reproductive system (uterus, ovary, cervix and vagina) and breast cancer was determined for 5,398 living alumnae, 2,622 of whom were former college athletes and 2,776 non-athletes, from data on medical and reproductive history, athletic training and diet. The former athletes had a significantly lower risk of cancer of the breast and reproductive system than did the non-athletes. The relative risk (RR), non-athletes/athletes, for cancers of the reproductive system was 2.53. 95% confidence limits (CL) (1.17, 5.47). The RR for breast cancer was 1.86, 95% CL (1.00, 3.47). The analysis controlled for potential confounding factors including age, family history of cancer, age of menarche, number of pregnancies, use of oral contraceptives, use of oestrogen in the menopausal period, smoking, and leanness. Of the college athletes, 82.4% had been on pre-college teams compared to 24.9% of the college non-athletes. We conclude that long term athletic training may lower the risk of breast cancer and cancers of the reproductive system.

Adult↗
PubMed1992

Local immunity in the male reproductive tract.

In previous studies we have demonstrated that the male urinary tract forms part of the common mucosal immune system, and that the gut contributes to local defences at this site. The question arises as to the extent to which the reproductive tract also forms part of the common mucosal immune system. Rats were immunized by a variety of routes designed to stimulate a local response in the intestine and/or the reproductive tract. Rats immunized only by the intratesticular (i.t.) route yielded no antibody-containing (ACC) response in any of the tissues examined. Intestinal immunization using intraperitoneal priming followed by intraduodenal challenge (i.p./i.d.) yielded a substantial IgA-specific ACC response in the jejunum, but no ACC were detectable in any of the reproductive tract tissues. However, when intestinal and testicular immunizations were combined, large numbers of IgA-specific antibodies were detected in all tissues examined. Chronic drainage of the thoracic lymphatic duct throughout the post-challenge period abrogated the ACC response in all tissues of the reproductive tract, indicating that the ACC appearing at these sites after immunization were of gut origin. The IgA-specific anti-OVA antibody detectable in serum, saliva and testis homogenate reflected the ACC counts in histological sections. The studies reported here confirm that the male reproductive tract does form part of a common mucosal immune system and that gut-associated lymphoid tissues may contribute cellular precursors for ACC, particularly those of IgA specificity, appearing in the tract after local challenge.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2004

Context-dependent autonomous self-fertilization yields reproductive assurance and mixed mating.

The evolution of self-fertilization in hermaphrodites is opposed by costs that decrease the value of self progeny relative to that of outcross progeny. However, self-fertilization is common in plants; 20% are highly selfing and 33% are intermediate between selfing and outcrossing. Darwin proposed an adaptive benefit of self-pollination in providing reproductive assurance when outcrossing is impossible. Moreover, if outcross pollen receipt is inconsistent within or between years, these conditions likewise favour self-pollination, and this can result in a mixture of self and outcross seed production (mixed mating). Despite wide acceptance, the reproductive assurance hypothesis has lacked the support of complete empirical evidence to show that variable pollination can create both the ecological and genetic conditions favouring self-pollination. We recently showed in Collinsia verna that during periods of infrequent pollinator visits, autonomous self-pollination boosted seed output per flower, the key ecological condition. Here we show low inbreeding depression and marker-based estimates of selfing, demonstrating that when the pollination environment in wild populations necessitates reproductive assurance, selfing rates increase. We provide a complete demonstration of reproductive assurance under variable pollination environments and mechanistically link reproductive assurance to intermediate selfing rates through mixed mating.

Breeding↗
PubMed2005

Reproductive factors and subtypes of breast cancer defined by hormone receptor and histology.

Reproductive factors are associated with reduced risk of breast cancer, but less is known about whether there is differential protection against subtypes of breast cancer. Assuming reproductive factors act through hormonal mechanisms they should protect predominantly against cancers expressing oestrogen (ER) and progesterone (PR) receptors. We examined the effect of reproductive factors on subgroups of tumours defined by hormone receptor status as well as histology using data from the NIHCD Women's Contraceptive and Reproductive Experiences (CARE) Study, a multicenter case-control study of breast cancer. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) as measures of relative risk using multivariate unconditional logistic regression methods. Multiparity and early age at first birth were associated with reduced relative risk of ER + PR + tumours (P for trend=0.0001 and 0.01, respectively), but not of ER - PR - tumours (P for trend=0.27 and 0.85), whereas duration of breastfeeding was associated with lower relative risk of both receptor-positive (P for trend=0.0002) and receptor-negative tumours (P=0.0004). Our results were consistent across subgroups of women based on age and ethnicity. We found few significant differences by histologic subtype, although the strongest protective effect of multiparity was seen for mixed ductolobular tumours. Our results indicate that parity and age at first birth are associated with reduced risk of receptor-positive tumours only, while lactation is associated with reduced risk of both receptor-positive and -negative tumours. This suggests that parity and lactation act through different mechanisms. This study also suggests that reproductive factors have similar protective effects on breast tumours of lobular and ductal origin.

Adult↗