首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
When widespread use of sex‐selective abortion and sex selection through assisted reproduction lead to severe harms to third parties and perpetuate discrimination, should these practices be banned? In this paper I focus on India and show why a common argument for a ban on sex selection fails even in these circumstances. I set aside a common objection to the argument, namely that women have a right to procreative autonomy that trumps the state's interest in protecting other parties from harm, and argue against the ban on consequentialist grounds. I perform a pairwise comparative analysis of sex selection and its plausible alternatives and argue that that the ban fails to improve the state of affairs relative to a scenario without a ban. The ban makes the situation worse, especially for mothers and their daughters. India should therefore repeal its ban on sex selection.  相似文献   

2.
Sex selection of children by pre‐conception and post‐conception techniques remains morally controversial and even illegal in some jurisdictions. Among other things, some critics fear that sex selection will distort the sex ratio, making opposite‐sex relationships more difficult to secure, while other critics worry that sex selection will tilt some nations toward military aggression. The human sex ratio varies depending on how one estimates it; there is certainly no one‐to‐one correspondence between males and females either at birth or across the human lifespan. Complications about who qualifies as ‘male’ and ‘female’ complicate judgments about the ratio even further. Even a judiciously estimated sex ratio does not have, however, the kind of normative status that requires society to refrain from antenatal sex selection. Some societies exhibit lopsided sex ratios as a consequence of social policies and practices, and pragmatic estimates of social needs are a better guide to what the sex ratio should be, as against looking to ‘nature’. The natural sex ratio cannot be a sound moral basis for prohibiting parents from selecting the sex of their children, since it ultimately lacks any normative meaning for social choices.  相似文献   

3.
OBJECTIVES--To determine the proportion of children whose sex was determined prenatally among those attending one Indian hospital and to identify factors which affect use of fetal sex determination. DESIGN--Cross sectional study using interviews with mothers. SETTING--Medical school hospital in Punjab, India. SUBJECTS--596 children delivered or seen for inpatient or outpatient care. MAIN OUTCOME MEASURES--Fetal sex determination, sex of child, number and sex of siblings, type of care received, socioeconomic status, and maternal education. RESULTS--Sex had been determined prenatally for fewer girls (5/236, 2%) than boys (49/360, 14%). Fetal sex determination had been done for only 2% (3/154) of first born boys compared with 18% (12/66) with one older sister and no older brother and 63% (30/48) with more than one older sister and no older brother. Only four boys whose sex had been determined prenatally had older brothers. The five girls whose sex had been determined prenatally either had a male twin or were incorrectly identified as male. Prenatal sex determination had been done for 21% (26/122) of boys admitted for inpatient care compared with 11% (19/173) seen as outpatients. Use of fetal sex determination increased with increasing monthly income (chi2 for trend = 6.384, P = 0.0115). None of the mothers who had had no education had used fetal sex determination, but among mothers with some education the frequency of use did not change with increasing education. The sex ratio of children born at the hospital rose from 107 boys/100 girls in 1982 to 132 boys/100 girls in 1993. CONCLUSIONS--Fetal sex determination was common, especially if the family already had daughters. Sex determination seems to be driven by a desire to have sons, with socioeconomic status and education having little effect. The lower prevalence of fetal sex determinations for girls is likely to be due to abortion of fetuses found to be female.  相似文献   

4.
The evolution of sex ratios and sex-determining systems   总被引:3,自引:0,他引:3  
Sex determination is a fundamental process governed by diverse mechanisms. Sex ratio selection is commonly implicated in the evolution of sex-determining systems, although formal models are rare. Here, we argue that, although sex ratio selection can induce shifts in sex determination, genomic conflicts between parents and offspring can explain why single-factor systems (e.g. XY/XX or ZW/ZZ) are common even in species that experience selection for biased sex ratios. Importantly, evolutionary shifts in sex determination do not always result in the biased production of sons and daughters sensu sex ratio theory. Thus, equal sex ratios might be an emergent character of sex-determining systems even when biased sex ratios are favored by selection.  相似文献   

5.
Summary This article examines how the sex composition of women's current children at the start of a pregnancy interval influences both fertility desires and the full range of reproductive actions women may take to realize them, including temporary contraception, abortion and sterilization, in Madhya Pradesh, India, where popular notions of ideal family size and sex composition are dominated by son preference. The analysis is conducted using a dataset of 9127 individual pregnancy intervals from a 2002 statewide representative survey of 2444 women aged 15-39 with at least one child. The results indicate that women's preferences go beyond a singular preference for male children, with the preferred composition of children being two boys and one girl. Women with this composition are 90% less likely to report having wanted another pregnancy (OR 0.097, p<0.01) relative to those with two girls. These preferences have significant implications for reproductive actions. While sex composition has no statistically significant effect on the use of temporary contraception, those with the preferred sex composition are twice as likely to attempt abortion (OR 2.436, p<0.01) and twelve times more likely to be sterilized (OR 12.297, p<0.01) relative to those with two girls only.  相似文献   

6.

Background

There are 44 million missing women in India. Gender bias; neglect of girls, infanticides and feticides are responsible. The sex ratio at birth can be used to examine the influence of antenatal sex selection on the sex ratio.

Materials and Methods

Records from 321,991 deliveries at one hospital over 11 decades were utilized. The middle year in each decade was taken as representative of the decade. Data from 33,524 deliveries were then analyzed. Data for each decade was combined with that of previous decades and compared to the data of subsequent decades to look for any change in the trend. Sex ratio in the second children against sex of the first child was studied separately.

Results

The mean sex ratio for the 110 years examined was 910 girls to 1000 boys (95% CI; 891 to 930). The sex ratio dropped significantly from 935 (CI: 905 to 967) before 1979, to 892 (CI: 868 to 918) after 1980 (P = 0.04). The sex ratio in the second child was significantly lower if the first child was a girl [716 (CI: 672 to 762] (P<0.001). On the other hand, there was an excess of girls born to mothers whose first child was boy [1140 girls per 1000 boys (CI: 1072 to 1212 P<0.001)].

Conclusions

The sex ratio fell significantly after 1980 when ultra sound machines for antenatal sex determination became available. The sex ratio in second children if the first was a girl was even lower. Sex selective abortions after antenatal sex determination are thus implicated. However data on second children especially the excess of girls born to mothers who have a previous boy seen in the decade before the advent of antenatal ultra sound machines, suggests that other means of sex selection are also used.  相似文献   

7.
Non-medical sex selection is premised on the notion that the sexes are not interchangeable. Studies of individuals who undergo sex selection for non-medical reasons, or who have a preference for a son or daughter, show that they assume their child will conform to the stereotypical roles and norms associated with their sex. However, the evidence currently available has not succeeded in showing that the gender traits and inclinations sought are caused by a “male brain” or a “female brain”. Therefore, as far as we know, there is no biological reason why parents cannot have the kind of parenting experience they seek with a child of any sex. Yet gender essentialism, a set of unfounded assumptions about the sexes which pervade society and underpin sexism, prevents parents from realising this freedom. In other words, unfounded assumptions about gender constrain not only a child’s autonomy, but also the parent’s. To date, reproductive autonomy in relation to sex selection has predominantly been regarded merely as the freedom to choose the sex of one’s child. This paper points to at least two interpretations of reproductive autonomy and argues that sex selection, by being premised on gender essentialism and/or the social pressure on parents to ensure their children conform to gender norms, undermines reproductive autonomy on both accounts.  相似文献   

8.
Sex determination in the flowers of maize involves the abortion of stamen or pistil development. Recent work investigating genes that control this process reveals that a microRNA is involved in both the sex determination of the male inflorescence and its growth pattern.  相似文献   

9.
Sex chromosomes in dioecious and polygamous plants evolved as a mechanism for ensuring outcrossing to increase genetic variation in the offspring. Sex specificity has evolved in 75% of plant families by male sterile or female sterile mutations, but well-defined heteromorphic sex chromosomes are known in only four plant families. A pivotal event in sex chromosome evolution, suppression of recombination at the sex determination locus and its neighboring regions, might be lacking in most dioecious species. However, once recombination is suppressed around the sex determination region, an incipient Y chromosome starts to differentiate by accumulating deleterious mutations, transposable element insertions, chromosomal rearrangements, and selection for male-specific alleles. Some plant species have recently evolved homomorphic sex chromosomes near the inception of this evolutionary process, while a few other species have sufficiently diverged heteromorphic sex chromosomes. Comparative analysis of carefully selected plant species together with some fish species promises new insights into the origins of sex chromosomes and the selective forces driving their evolution.  相似文献   

10.
This paper explores the factors that influence the practice of induced abortion in a very low fertility society, with particular emphasis on son preference and three distinct religions: Confucianism, Buddhism and Christianity. Using multivariate logistic regression models fitted by the generalized estimating equation (GEE) method, this paper analysed the data collected by the 2000 Korea National Fertility and Family Health Survey of 6348 married women aged 15-49 years with a total of 1217 pregnancy outcomes. The results showed that the likelihood of induced abortions in women with two or more children, compared with those with one child, was significantly influenced by the sex composition of the previous children: odds ratio (OR)=12.71 (95% CI=5.49, 29.42) for women with only son(s), and OR=3.91 (95% CI=1.67, 9.14) for women with only daughter(s). At parity two, women with two sons were much more likely to have induced abortions than women with two daughters (OR=5.88, 95% CI=2.70, 12.85). Although Buddhist women were not significantly different from Confucian women in induced abortion practice, Christian women were much less likely than Confucian women to have an induced abortion (OR=0.39, 95% CI=0.18, 0.88 for women with only sons and OR=0.44, 95% CI=0.24, 0.81 for women with two children). This suggests that even in this very low fertility society, son preference and religious affiliation are significant predictors of women's practice of induced abortion.  相似文献   

11.
性别控制是人类很早就关心的研究领域, 许多重要的经济性状与性别有直接的关系。控制受精环境即可控制性别, 这种方法不需昂贵的仪器设备或者药品, 易实践, 可普遍应用, 其经济效益和社会效益难以估量。文章综述了受精环境对哺乳动物性别形成影响的研究进展。这些环境因素包括母体生殖道中精氨酸含量、胚胎发育过程中子宫内葡萄糖浓度、输精时卵母细胞成熟程度以及哺乳动物受孕时生殖激素的水平等方面, 为进一步开展性别控制研究积累一定的资料。  相似文献   

12.
Sex determination is an intriguing system in trioecious papaya. Over the past seven decades various hypotheses, based on the knowledge and information available at the time, have been proposed to explain the genetics of the papaya's sex determination. These include a single gene with three alleles, a group of closely linked genes, a genic balance of sex chromosome over autosomes, classical XY chromosomes, and regulatory elements of the flower development pathway. Recent advancements in genomic technology make it possible to characterize the genomic region involved in sex determination at the molecular level. High density linkage mapping validated the hypothesis that predicted recombination suppression at the sex determination locus. Physical mapping and sample sequencing of the non-recombination region led to the conclusion that sex determination is controlled by a pair of primitive sex chromosomes with a small male-specific region (MSY) of the Y chromosome. We now postulate that two sex determination genes control the sex determination pathway. One, a feminizing or stamen suppressor gene, causes stamen abortion before or at flower inception while the other, a masculinizing or carpel suppressor gene, causes carpel abortion at a later flower developmental stage. Detailed physical mapping is beginning to reveal structural details about the sex determination region and sequencing is expected to uncover candidate sex determining genes. Cloning of the sex determination genes and understanding the sex determination process could have profound application in papaya production.  相似文献   

13.
Krishnan V 《Social biology》1991,388(3-4):249-257
This paper examines a number of demographic and sociocultural factors (e.g., age, marital status, family size, religion, religious assiduity, sex-role ideology) as predictors of women's attitudes toward abortion, using data from the Canadian Fertility Survey of 1984. The findings suggest that women's abortion attitudes are to a greater extent based on ideological positions. It appears that anti-abortion stance affects those women who are religious, presumably by increasing the relationship between their general sex-role ideological stances and abortion attitudes. Abortion attitudes also vary according to a woman's education, her size, and province/region of residence.  相似文献   

14.
Pryer JA  Rogers S  Rahman A 《Social biology》2003,50(3-4):259-269
This study looks at women from the slums in Mohammadpur, Dhaka, Bangladesh, where 54 percent of women's BMI was less than 18.5. Fifty percent of the Dhaka slum population lived below the poverty line. Logistic regression showed that women with income above 1,500 taka per capita were 1.78 times more likely to have a higher BMI (odds ratio 1.7863; CI = 0.671-3.639). Women with their own savings were 1.89 times more likely to have higher BMI (odds ratio 1.879; CI = 0.01163-1.6431). Women were 4.5 times more likely to have a higher BMI when food expenditure per capita above 559 taka per month (odds ratio 4.55; CI = 1.0302-8.0799). Women were 1.82 times more likely to have higher BMI when there was a break even situation in financial status (odds ratio 1.8212; CI = -015709-3.6285). Female headed households were 3.3 times more likely to have a higher BMI compared to women living in male headed households (odds ratio 3.2966; CI = 0.33711-6.25620). Women who work 15-23 days per month were 2.3 times more likely to have a higher BMI (odds ratio 2.33; CI = 0.1133-4.5600). Women who are the budget manager are 1.12 times more likely to have a higher BMI (odds ratio 1.125; CI = 0.29296-2.0966). Where as a husband who beats his wife is 1.83 more likely to have a poorer BMI (odds ratio 1.8312; CI = -3.72596-0.17508). Women who have no marriage documents and women who take days off due to illness less than 11 days per month were more likely to have a poorer BMI (odds ratio 0.5567; CI = -0.049339-2.8379; odds ratio 0.7569; CI = 0.183167-2.0002). Women's nutritional status and well being can influence their ability to provide for themselves and their families and the demonstration of a relationship between measures of women's autonomy and control in the household and women's nutritional status is an important indication of the importance of these sociological constructs. Women's participation in work outside the home may be a factor increasing their autonomy. The identification of relationships between women's autonomy and control and their physical well being should provide further leverage for policy change that will enable women to escape some traditional roles and to contribute as more equal partners with men in the future of Bangladeshi society.  相似文献   

15.
CHALLENGING THE RHETORIC OF CHOICE IN PRENATAL SCREENING   总被引:1,自引:0,他引:1  
Prenatal screening, consisting of maternal serum screening and nuchal translucency screening, is on the verge of expansion, both by being offered to more pregnant women and by screening for more conditions. The Society of Obstetricians and Gynaecologists of Canada and the American College of Obstetricians and Gynecologists have each recently recommended that screening be extended to all pregnant women regardless of age, disease history, or risk status. This screening is commonly justified by appeal to the value of autonomy, or women's choice. In this paper, I critically examine the value of autonomy in the context of prenatal screening to determine whether it justifies the routine offer of screening and the expansion of screening services. I argue that in the vast majority of cases the option of prenatal screening does not promote or protect women's autonomy. Both a narrow conception of choice as informed consent and a broad conception of choice as relational reveal difficulties in achieving adequate standards of free informed choice. While there are reasons to worry that women's autonomy is not being protected or promoted within the limited scope of current practice, we should hesitate before normalizing it as part of standard prenatal care for all.  相似文献   

16.
Sex determining (SD) mechanisms are highly variable between different taxonomic groups and appear to change relatively quickly during evolution. Sex ratio selection could be a dominant force causing such changes. We investigate theoretically the effect of sex ratio selection on the dynamics of a multi-factorial SD system. The system considered resembles the naturally occurring three-locus system of the housefly, which allows for male heterogamety, female heterogamety and a variety of other mechanisms. Sex ratio selection is modelled by assuming cost differences in the production of sons and daughters, a scenario leading to a strong sex ratio bias in the absence of constraints imposed by the mechanism of sex determination. We show that, despite of the presumed flexibility of the SD system considered, equilibrium sex ratios never deviate strongly from 1 : 1. Even if daughters are very costly, a male-biased sex ratio can never evolve. If sons are more costly, sex ratio can be slightly female biased but even in case of large cost differences the bias is very small (<10% from 1 : 1). Sex ratio selection can lead to a shift in the SD mechanism, but cannot be the sole cause of complete switches from one SD system to another. In fact, more than one locus remains polymorphic at equilibrium. We discuss our results in the context of evolution of the variable SD mechanism found in natural housefly populations.  相似文献   

17.
18.
Ellis L  Bonin S 《Social biology》2002,49(1-2):35-43
Because women are more likely than men to use social status as a criterion in mate selection, evolutionary theory has led to the hypothesis that higher proportions of males will be born to parents of high social status than to parents of low status. To date, the research that has tested this deduction has not provided consistent support. This could be partly due to the small sample size in several of the studies. The present study tested the hypothesis using 6 different social status measures provided by more than 11,000 United States and Canadian college students. The offspring sex ratio was measured by asking the students their own sex plus that of each of their siblings. No evidence was found to support the hypothesis that parental social status has any significant effect on the sex ratio of offspring.  相似文献   

19.
This study used data from a community-based survey to examine women's experiences of abortion in Nigeria. Fourteen percent of respondents reported that they had ever tried to terminate a pregnancy, and 10% had obtained an abortion. The majority of women who sought an abortion did so early in the pregnancy. Forty-two percent of women who obtained an abortion used the services of a non-professional provider, a quarter experienced complications and 9% sought treatment for complications from their abortions. Roughly half of the women who obtained an abortion used a method other than D&C or MVA. The abortion prevalence and conditions under which women sought abortions varied by women's socio-demographic characteristics. Because abortion is illegal in Nigeria except to save the woman's life, many women take significant risks to terminate unwanted pregnancies. Reducing the incidence of unwanted pregnancy and unsafe abortion can significantly impact the reproductive health of women in Nigeria.  相似文献   

20.
黑腹果蝇的性别控制   总被引:4,自引:0,他引:4  
王慧超  朱勇  夏庆友 《遗传》2003,25(1):97-101
性别的形成包括两个过程,即性别决定和性别分化。果蝇的性别控制研究包括性别决定、性别分化、性别鉴定、性别诱导和性别控制5个方面。性别决定是在两种不同发育途径之间的选择,它提供了一个研究基因调控的模式系统。果蝇的性别决定问题已经研究得相当详细[1]。性别分化是使胚胎向着雌性或雄性发育的过程,决定了性别表型。果蝇的性别分化也取得了不少研究成果。近年来,许多重要的性别调控基因已被克隆和鉴定。随着果蝇基因组全序列测定的完成,果蝇的性别控制研究将会更为深入而完善。本文对与黑腹果蝇性别决定和性别分化相关的一些问题进行综述。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号