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1.
A fertility survey of unmarried adolescents and young adults (953 males and 829 females) in Greater Accra and Eastern regions of Ghana revealed that a substantial proportion of the respondents were sexually experienced. Overall, 66.8% of the males and 78.4% of the females were sexually experienced. The mean ages (+/- SD) of the males and females were 15.5 +/- 2.5 and 16.2 +/- 2.0 years, respectively. Most respondents claimed to have received adequate information on reproductive health and sexually transmitted diseases (STDs), including AIDS. However, 20% and 30% of the respondents in peri-urban and rural areas, respectively, did not know that a girl could get pregnant the first time she has sexual intercourse. The incidence of pregnancy among the unmarried female respondents was relatively high (37%), and was higher in urban than in rural areas. Approximately 47% of those who had ever been pregnant reported that they had had an abortion. Levels of contraceptive awareness were high (98.2% among males and 95.5% among females) but many still engaged in unprotected sexual relations. The most commonly used methods were the condom and the pill. The main reasons given for non-use were that they did not think about contraception, were concerned about the safety of contraceptives, and partner objection. These findings point to the need for targeting of unmarried adolescents and young adults with information on reproductive health and family planning to increase their awareness of the risks of pregnancy, STDs and HIV infection. 相似文献
2.
Zarin P. Machanda Ian C. Gilby Richard W. Wrangham 《International journal of primatology》2013,34(5):917-938
Although male–female relationships can offer a number of advantages such as protection or social support, they are poorly studied among primates compared to same-sex relationships. We used 12 yr of data from the Kanyawara chimpanzee community to compare three independent measures of association (party association, 5m association, and grooming) among all adult dyads. Party association exhibited by male–female dyads was of intermediate strength between strong male–male and weak female–female association. Male–female dyads were less likely to be within 5m of one another and to groom as male–male dyads, but equally likely to be within 5m and more likely to groom as female–female dyads. Variation in male–female association strength was not related to male rank but was affected by female ranging patterns and female reproductive states. Females with core areas in the center of the home range were more likely to be in parties with males but did not show higher spatial proximity or grooming indices compared to females ranging in the periphery. Party association and 5m indices were higher for dyads of males and estrous females compared to those with anestrous females. These results indicate that male–female dyads are likely to associate with one another more often than female–female dyads because of overlapping ranging patterns and short-term changes in female reproductive state. We conclude that male and female chimpanzees do not exhibit proximity and grooming patterns indicative of strong affiliative bonds. This study also highlights the importance of using multiple independent measures of bond strength in studies of primate social dynamics. 相似文献
3.
Yve Stoebel-Richter Kristina Geue Ada Borkenhagen Elmar Braehler Kerstin Weidner 《PloS one》2012,7(12)
Objective
The use of reproductive medical treatments has become increasingly routine in recent years. This paper reports on a study of how different aspects of modern reproductive medicine are perceived by the German population.Design
Findings from a nationally representative sample of 2110 men and women aged 18 to 50 are presented. Participants responded to a questionnaire seeking self-report information about attitudes and knowledge regarding different aspects of reproductive medicine.Results
The majority of respondents had already heard or read something about reproductive medicine; knowledge gaps were prevalent in men and individuals with lower levels of education. The decrease in female fertility usually was underestimated, whereas both the number of involuntarily childless couples and the success rate of reproductive medical treatment were overestimated. One-third of participants would make use of reproductive medicine to have their own child.Conclusion
This study revealed inadequacies in the knowledge of the German general population regarding reproductive medicine. Despite the low interest and poor knowledge of the topic, a broad acceptance of reproductive medical methods was reported. The results illustrate the need for adequate information transfer regarding female fertility as well as success rate and risks of reproductive medical interventions. 相似文献4.
OBJECTIVE: To assess the prevalence of psychological abuse, physical assault, and discrimination on the basis of gender and sexual orientation, and to examine the prevalence and impact of sexual harassment in residency training programs. DESIGN: Self-administered questionnaire. SETTING: McMaster University, Hamilton, Ont. PARTICIPANTS: Residents in seven residency training programs during the academic year from July 1993 to June 1994. Of 225 residents 186 (82.7%) returned a completed questionnaire, and 50% of the respondents were women. OUTCOME MEASURES: Prevalence of psychological abuse, physical assault and discrimination on the basis of gender and sexual orientation experienced by residents during medical training, prevalence and residents'' perceived frequency of sexual harassment. RESULTS: Psychological abuse was reported by 50% of the residents. Some of the respondents reported physical assault, mostly by patients and their family members (14.7% reported assaults by male patients and family members, 9.8% reported assaults by female patients and family members), 5.4% of the female respondents reported assault by male supervising physicians. Discrimination on the basis of gender was reported to be common and was experienced significantly more often by female residents than by male residents (p < 0.01). Ten respondents, all female, reported having experienced discrimination on the basis of their sexual orientation. Most of the respondents experienced sexual harassment, especially in the form of sexist jokes, flirtation and unwanted compliments on their dress or figure. On average, 40% of the respondents, especially women (p < 0.01), reported experiencing offensive body language and receiving sexist teaching material and unwanted compliments on their dress. Significantly more female respondents than male respondents stated that they had reported events of sexual harassment to someone (p < 0.001). The most frequent emotional reactions to sexual harassment were embarassment (reported by 24.0%), anger (by 23.4%) and frustration (20.8%). CONCLUSION: Psychological abuse, discrimination on the basis of gender and sexual harassment are commonly experienced by residents in training programs. A direct, progressive, multidisciplinary approach is needed to label and address these problems. 相似文献
5.
Andreas Filser Kieron Barclay Amber Beckley Caroline Uggla Sebastian Schnettler 《Evolution and human behavior》2021,42(3):212-222
There is widespread concern in both the popular and academic literature that a surplus of men in a population intensifies mating competition between men, particularly unpartnered men, resulting in increased violence towards both men and women. Recent contributions challenge this perspective and argue that male mating competition and levels of violence will be higher when sex ratios are female-skewed. Existing empirical evidence remains inconclusive. We argue that this empirical ambiguity results from analyses of aggregate-level data, which put inferences at risk of ecological fallacies. Our analysis circumvents such problems by using individual-level, longitudinal demographic register and police data for the Stockholm metropolitan area, Sweden (1990–2003, n = 758,498). These data allow us to investigate the association between municipality-level sex ratios and violent offending (homicide, assault, threat, and sexual crimes) while adjusting for sociodemographic factors. Results suggest that aggregated offending rates are negatively associated with male-skewed sex ratios, whereas individual-level violent offending correlates positively with male-skews. We find that the more-men-more-violence association holds particularly for male violence against other men, but is insignificant for violence against women. Moreover, the association is significant among childless men, but not among fathers. However, robustness checks question the causality of these associations. Female violent offending is positively, albeit due to a low number of cases, insignificantly associated with male-skews. Moreover, both male and female non-violent offending is higher in male-skewed municipalities. We discuss the implications with regard to the theoretical debate and problems of unobserved heterogeneity in the sex ratio literature. 相似文献
6.
《Ethology and sociobiology》1995,16(2):99-123
Criminologists have drawn attention to the fact that crime peaks in the teens and early 20s and that this pattern shows invariance over culture, history, offense, and sex. Wilson and Daly (1985) have proposed that among young, disadvantaged males, the age-crime curve reflects risky tactics aimed at averting “reproductive death.” Though young women's rate of involvement in violent crime is much lower than men's, they also show a similar age-violence curve for assault. This paper proposes that this may be the result of aggressive mate selection among young women and that, under certain specified circumstances, women may engage in low-key intrasexual strategies in addition to epigamic strategies. This paper reviews material on sex differences in violent crime and in mate selection strategies, and offers predictions about the likely circumstances under which females will use intrasexual strategies. The scant available data on female adolescent fighting suggest that female-female assaults are more common than official statistical estimates and that they are frequently triggered by three key issues related to reproductive fitness: management of sexual reputation, competition over access to resource-rich young men, and protecting heterosexual relationships from takeover by rival women. 相似文献
7.
Vlassoff C 《Journal of biosocial science》2012,44(3):345-356
This paper compares the desired fertility of rural Indian women in 1987 with their actual fertility in 2007. Seventy-one respondents who stated definite fertility intentions and had fewer children than desired in 1987 were re-interviewed 20 years later, as part of a larger study. The results indicated that these women had fewer children than intended and stopped childbearing once they reached, or approximated, their desired number of sons. The majority had been sterilized, indicating broad acceptance of lower fertility among rural women and the success of India's family planning efforts, although the practice of sex determination seems also to have played a role. These findings echo those of an earlier longitudinal study of reproductive intentions and outcomes in the same community, demonstrating the persistence of son preference in determining reproductive behaviour, even in the context of low overall fertility. The paper concludes with a discussion of the policy and programme implications of the study's findings. 相似文献
8.
Maria Emilia Yamamoto Fabíola S. Albuquerque Nívia A. Lopes Eric S. Ferreira 《Acta ethologica》2008,11(2):95-99
Callitrichids are communal breeders that lack sexual dimorphism, and only a few studies have examined behavioral gender differences among them. The purpose of this study was to investigate gender differences in infant carrying in 16 captive and seven wild common marmoset groups. Our results showed that female–female twin pairs were carried significantly more often by fathers than were male–male and male–female pairs both in the wild and in captivity. We suggest these differences may be related to different reproductive potentials of male and female Callithrix jacchus and possibly to future breeding competition among females. 相似文献
9.
High calf mortality in bottlenose dolphins in the Bay of Islands,New Zealand–a local unit in decline
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Gabriela Tezanos‐Pinto Rochelle Constantine Fabiana Mourão Joanne Berghan C. Scott Baker 《Marine Mammal Science》2015,31(2):540-559
Bottlenose dolphins (Tursiops truncatus) in the Bay of Islands, New Zealand, have been studied for almost two decades. Since 2003, fewer than 150 dolphins visited the bay during each season and the local unit has declined 7.5% annually from 1997 to 2006. The causes of decline are unclear but probably include mortality and emigration. Here, we used a long‐term database to estimate reproductive parameters of female bottlenose dolphins including recruitment rates. A total of 704 surveys were conducted in which 5,577 sightings of 408 individually identified dolphins were collected; of these 53 individuals were identified as reproductive females. The calving rate increased between periods (1997–1999 = 0.13, CL = 0.07–0.21; 2003–2005 = 0.25, CL = 0.16–0.35 calves/reproductive female/year). A 0.25 calving rate suggests that on average, a female gives birth only once every four years, which is consistent with the estimated calving interval (4.3 yr, SD = 1.45) but still is lower than values reported for other populations. Conversely, apparent mortality rates to age 1+ (range: 0.34–0.52) and 2+ (range: 0.15–0.59) were higher than values reported elsewhere. The high apparent calf mortality in conjunction with a decline in local abundance, highlight the vulnerability of bottlenose dolphins in the Bay of Islands. Long‐term studies are required to understand the causes of high calf mortality and the decline in local abundance. Meanwhile, management should focus on minimizing sources of anthropogenic disturbance and enforcing compliance with current legislation. 相似文献
10.
《Ethology and sociobiology》1993,14(6):391-396
A study of female reproductive histories from nineteenth-century Utah shows that although women who married polygynously had fewer children, their number of grandchildren was equal to that of women who married monogamously. Women who chose to marry high-status men polygynously traded decreased fertility for enhanced reproductive performance of offspring. High status can be associated with low fertility and yet still be consistent with fitness optimization. These results suggest how female reproductive decisions influence social structure and challenge previous assumptions concerning proximate measures of fitness. 相似文献
11.
The forkhead-associated (FHA) domain is involved in protein–protein interaction by recognizing a phosphothreonine epitope on target proteins. In this study, we investigated in planta functions of the Arabidopsis FHA domain 2. AtFHA2 was mainly localized in the nucleus. Arabidopsis fha2 null mutants grew normally during the vegetative stage, but had severely reduced fertility during reproductive stage. The reduced fertility was mainly caused by defective stamen filament elongation, while female flower parts of the mutants were fertile. Additionally, the mutants had fewer stamens than the wild type and the vegetative organs of the mutants, such as cotyledons and leaves, had increased ploidy. These results suggest that AtFHA2 may play a role in a signaling pathway for the control of plant organ development. 相似文献
12.
Low mineral density of a weight-bearing bone among adult women in a high fertility population
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Jonathan Stieglitz Bret A. Beheim Benjamin C. Trumble Felicia C. Madimenos Hillard Kaplan Michael Gurven 《American journal of physical anthropology》2015,156(4):637-648
Evolutionary theories of aging posit that greater reproductive effort causes somatic decline given a fundamental trade-off between investing energy in reproduction and repair. Few studies in high fertility human populations support this hypothesis, and problems of phenotypic correlation can obscure the expected trade-off between reproduction and somatic condition. This cross-sectional study investigates whether greater reproductive effort is associated with reduced calcaneal bone mineral density (BMD) among female Tsimane forager-farmers of lowland Bolivia. We also investigate whether female Tsimane BMD values are lower than sex- and age-matched US reference values, despite the fact that Tsimane engage in higher physical activity levels that can increase mechanical loading. To measure calcaneal BMD, quantitative ultrasonography was performed on 130 women (mean ± SD age = 36.6 ± 15.7, range = 15–75) that were recruited regardless of past or current reproductive status. Anthropometric and demographic data were collected during routine medical exams. As predicted, higher parity, short inter-birth interval, and earlier age at first birth are associated with reduced BMD among Tsimane women after adjusting for potential confounders. Population-level differences are apparent prior to the onset of reproduction, and age-related decline in BMD is greater among Tsimane compared with American women. Greater cumulative reproductive burden may lower calcaneal BMD individually and jointly with other lifestyle and heritable factors. Fitness impacts of kin transfers in adulthood may determine the value of investments in bone remodeling, and thus affect selection on age-profiles of bone mineral loss. Am J Phys Anthropol 156:637–648, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
13.
BackgroundThe growth in e-cigarette use may be driven by the perception that they are a safer, healthier alternative to conventional cigarettes. However, their long-term health implications are not well known and use is discouraged by most cancer societies. It is currently unclear how cancer survivors perceive the risks associated with e-cigarette and how this may influence use in this population.MethodsA cross-sectional analysis was conducted using the Health Information National Trends Survey (HINTS) (Years 2017–2019). Our primary study outcome was the perception of harm associated with e-cigarettes compared to traditional cigarettes among adults with and without a self-reported history of cancer. We used logistic regression analyses assessing the association of a cancer history with the perception that e-cigarettes are as much or more harmful than cigarettes.ResultsA total of 11,846 respondents (weighted population estimate 243,728,483) were included. Of these, 26.6% reported a history of cancer. The proportion of cancer survivors who perceived e-cigarettes to be as much or more harmful than conventional cigarettes was similar to non-cancer respondents (70.6% vs 68.3%, P = 0.35). There was no difference in perception of harm among cancer and non-cancer respondents, adjusted for sociodemographic factors (OR 0.82, 95% CI 0.6–1.1). Past (OR 9.06, 95% Cl 5.06–16.20) and never e-cigarette use (OR 23.40, 95% Cl 13.56–40.38) as well as having a history of cardiopulmonary disease (OR 1.28, 95% Cl 1.05–1.56) was associated with higher odds of perceiving e-cigarettes to be as much or more harmful.ConclusionCancer survivors commonly perceive e-cigarettes to be as much or more harmful than traditional cigarettes though these findings are similar to perceptions among adults without a history of cancer. There is a strong association with avoidance of e-cigarette products among those who perceive them to be harmful. 相似文献
14.
Valérie A. M. Schoof Katharine M. Jack Toni E. Ziegler 《International journal of primatology》2014,35(3-4):643-660
Reproductive success is linked to dominance in male primates, reflecting the benefits of male competition. However, not all males compete successfully, suggesting that the costs of obtaining and maintaining high dominance status are significant. Here we examine the fecal metabolites of testosterone (fT) and dihydrotestosterone (fDHT) as bioactive androgens reflecting male reproductive effort, as well as fecal glucocorticoid (fGC) excretion as an index of stress in male white-faced capuchins (Cebus capucinus). We investigated the influence of female fertility (periovulatory vs. nonovulatory) on the hormonal responses of alpha and subordinate males. Over a 17-mo field season, we collected and analyzed weekly fecal samples (N = 992) from all 14 adult (> 10 yr) and subadult (≥ 6–10 yr) males residing in three study groups in the Santa Rosa Sector of the Área de Conservación Guanacaste, Costa Rica. Fecal samples (N > 2250) were also collected from group females (N = 28) to identify the fertile period using progesterone and estradiol assays. Alpha males had significantly higher fT, fDHT, and fGC levels than subordinate males independent of female reproductive state; further, adult subordinates had significantly higher fT, but not fDHT or fGC, than subadult subordinates. Male fT, fDHT, and fGC levels were significantly higher in the presence of fertile females, regardless of male dominance status and age. These findings indicate that the higher reproductive effort of alpha males comes with some costs (increased fGCs), and the presence of periovulatory females is associated with specific endocrine responses reflecting male reproductive effort and stress in white-faced capuchins. 相似文献
15.
Floral-colour polymorphism in rewardless orchids has been hypothesized to be maintained by means of naïve insects, which after visiting a flower without reward will tend to fly elsewhere, looking for a flower of a different colour. In this study, levels of male and female reproductive success were monitored in Southern Italy populations of the deceptive orchid Dactylorhiza sambucina, through field observations over 3 years. These populations were characterized by the presence of a rare pink morph which is sympatric with the more frequent yellow and red morphs. In addition, final plant fertility was evaluated through percentages of embryo-containing seeds produced in both natural conditions and hand-pollination experiments. Results showed that pollinator preferences were independent of the morph frequencies and thus do not promote the predicted negative frequency-dependent selection. Although yellow and pink morphs showed significantly higher male reproductive success (RS), we found comparable levels of female RS, which suggest that pollinator behaviour cannot be the main mechanism which maintains this polymorphism. Interestingly, we found different percentages of embryo-containing seeds in fruits set under natural conditions as well as in those obtained from experimental crosses. In particular, pink morph showed a very low intrinsic fertility. Moreover, fertility in intra- was higher than in inter-morph crosses. To our knowledge, this is the first study pointing out the occurrence in the orchid family of post-pollination reproductive barriers. Findings are discussed in light of present hypothesis on the evolution and maintenance of colour polymorphism in deceptive orchids and other angiosperms. 相似文献
16.
Kasey A. Reynolds Natalia M. Grindler Julie S. Rhee Amber R. Cooper Valerie S. Ratts Kenneth R. Carson Emily S. Jungheim 《PloS one》2015,10(5)
Fertility is important to women and men with cancer. While options for fertility preservation (FP) are available, knowledge regarding the medical application of FP is lacking. Therefore we examined FP practices for cancer patients among reproductive endocrinologists (REs). A 36 item survey was sent to board-certified REs. 98% of respondents reported counseling women with cancer about FP options. Oocyte and embryo cryopreservation were universally offered by these providers, but variability was noted in reported management of these cases—particularly for women with breast cancer. 86% of the respondents reported using letrozole during controlled ovarian stimulation (COS) in patients with estrogen receptor positive (ER+) breast cancer to minimize patient exposure to estrogen. 49% of respondents who reported using letrozole in COS for patients with ER+ breast cancer reported that they would also use letrozole in COS for women with ER negative breast cancer. Variability was also noted in the management of FP for men with cancer. 83% of participants reported counseling men about sperm banking with 22% recommending against banking for men previously exposed to chemotherapy. Overall, 79% of respondents reported knowledge of American Society for Clinical Oncology FP guidelines—knowledge that was associated with providers offering gonadal tissue cryopreservation (RR 1.82, 95% CI 1.14–2.90). These findings demonstrate that RE management of FP in cancer patients varies. Although some variability may be dictated by local resources, standardization of FP practices and communication with treating oncologists may help ensure consistent recommendations and outcomes for patients seeking FP. 相似文献
17.
Logan Luevano Chris Sutherland Stephanie J. Gonzalez Raisa HernndezPacheco 《Ecology and evolution》2022,12(1)
Adversity early in life can shape the reproductive potential of individuals through negative effects on health and life span. However, long‐lived populations with multiple reproductive events may present alternative life history strategies to optimize reproductive schedules and compensate for shorter life spans. Here, we quantify the effects of major hurricanes and density dependence as sources of early‐life ecological adversity on Cayo Santiago rhesus macaque female reproduction and decompose their effects onto the mean age‐specific fertility, reproductive pace, and lifetime reproductive success (LRS). Females experiencing major hurricanes exhibit a delayed reproductive debut but maintain the pace of reproduction past debut and show a higher mean fertility during prime reproductive ages, relative to unaffected females. Increasing density at birth is associated to a decrease in mean fertility and reproductive pace, but such association is absent at intermediate densities. When combined, our study reveals that hurricanes early in life predict a delay‐overshoot pattern in mean age‐specific fertility that supports the maintenance of LRS. In contrast to predictive adaptive response models of accelerated reproduction, this long‐lived population presents a novel reproductive strategy where females who experience major natural disasters early in life ultimately overcome their initial reproductive penalty with no major negative fitness outcomes. Density presents a more complex relation with reproduction that suggests females experiencing a population regulated at intermediate densities early in life will escape density dependence and show optimized reproductive schedules. Our results support hypotheses about life history trade‐offs in which adversity‐affected females ensure their future reproductive potential by allocating more energy to growth or maintenance processes at younger adult ages. 相似文献
18.
Anne Savage Susan E. Shideler Luis H. Soto Jaime Causado L. Humberto Giraldo Bill L. Lasley Charles T. Snowdon 《American journal of primatology》1997,43(4):329-337
Reproductive patterns of wild cotton-top tamarin (Saguinus oedipus) females located in La Reserva Forestal Protectora Serranía de Coraza-Montes de María in Colosó, Colombia, were examined using long-term behavioral observations and fecal steroid analysis. Using an enzyme immunoassay, we analyzed fecal samples for E1C and PdG. Comparisons of reproductive cycles of a reproductively active female and her daughters were made. An inhibition of ovarian cycles has been observed in daughters living in their families. However, daughters also exhibited normal ovarian cycling that subsequently resulted in pregnancy. Factors influencing the fertility are discussed as they relate to the reproductive strategies of wild cotton-top tamarin females. Am. J. Primatol. 43:329–337, 1997. © 1997 Wiley-Liss, Inc. 相似文献
19.
Angiotensin-converting enzyme (ACE), a key enzyme in the renin– angiotensin–aldosterone system, converts angiotensin I to angiotensin II. Ethnic origin should be carefully considered in studies pertaining to ACE I/D genotype and disease etiology. This study was evaluated between the ACE gene I/D polymorphism and female infertility in the Saudi population. Out of a A total of 300 women who participated in this study genomic DNA samples from the 150 infertile and 150 fertile women’s were isolated who has participated in this study. Genomic DNA was isolated using an Invitrogen kit according to the manufacturer’s protocol, and D allele specific primers were used for amplification by polymerase chain reaction. Electrophoresis was carried out on a 2% agarose gel. The mean age and BMI of the cases and controls were similar (p > 0.05), and a significant association was noted between the family history and female infertility (p = 0.0001). The D allele (OR: 1.67 [95% CI: 1.18–2.35], p = 0.003), DD genotype (OR: 2.46 [95% CI: 1.20–5.02], p = 0.01) and dominant model (OR: 1.97 [95% CI: 1.00–3.88], p = 0.04) were significantly associated with female infertility or fertility. The results of this study show that the ACE polymorphism plays an important role in female infertility in the Saudi population. 相似文献