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Gender selection in China: its meanings and implications.

With the advancement of assisted reproduction technologies, people are offered wider choices to choose the gender of their offspring and to construct 'ideal-typed' families with specific gender structure. Gender selection is welcomed by many societies with gender-specific preference, especially those patriarchal societies such as Chinese communities. It is not only a medical procedure but also a social orientation, which reveals much of the underlying preference towards gender. This paper explores the cultural dimensions to gender selection and its psychosocial meanings and implications in Chinese societies, especially after the establishment of One Child Policy in China. Problems associated with son preference in the culture with strong gender stereotyping are addressed. We believe that gender selection for social reasons should not be allowed since undesirable outcomes will be resulted under such strict population control program.

China↗

The 50 million missing women.

The epidemic of gender selection is ravaging countries like India & China. Approximately fifty million women are "missing" in the Indian population. Generally three principle causes are given: female infanticide, better food and health care for boys and maternal death at childbirth. Prenatal sex determination and the abortion of female fetuses threatens to skew the sex ratio to new highs. Estimates of the number of female fetuses being destroyed every year in India vary from two million to five million. This review from India attempts to summarize all the currently available methods of sex selection and also highlights the current medical practice regards the subject in south-east Asia.

Female↗

The antral follicle count predicts the outcome of pregnancy in a controlled ovarian hyperstimulation/intrauterine insemination program.

PURPOSE: Our purpose was to test whether age-related changes in antral follicle counts can predict the pregnancy outcome in the early follicular phase of a controlled ovarian hyperstimulation/intrauterine insemination (COH/IUI) program. METHODS: A selected group of 107 women (36 healthy women requesting child sex preselection, 52 women with unexplained infertility, and 19 with minimal endometriosis) who underwent controlled ovarian hyperstimulation with clomiphene citrate (CC) plus human menopausal gonadotrophin (hMG) and subsequent intrauterine insemination were enrolled in the study. Transvaginal ultrasonography (7.0 MHz) was used to determine the total number of antral follicles (2-8 mm) in the right and left ovaries. The association among the antral follicle count, age, dominant follicle, and estradiol (E2) level on the day of human chorionic gonadotropin (hCG) was analyzed. The association of the pregnancy rate and OHSS with the antral follicle count, dominant follicle count, and age was also examined. RESULTS: The total antral follicle number decreased with age (P < 0.0001). Dominant follicle number increased with total antral follicle number in women who received CC plus hMG/ IUI(P < 0.0001). The pregnant group had a higher number of antral follicle and dominant follicles in comparison with the nonpregnant group (P < 0.01 and P < 0.02, respectively). The E2 level on the day of hCG injection increased positively with the total number of antral follicles (P < 0.0001) and the total number of dominant follicles (P < 0.0001). In women aged younger than 35 years, the pregnancy rate and dominant follicle number rose as the number of antral follicles increased (P < 0.03 and P < 0.0001, respectively). The pregnancy rate was low (2/39) in women aged older than 35 years regardless of the number of antral follicles (P < 0.05) and the extent of hMG administration (P < 0.02). Women aged older than 35 also produced fewer dominant follicles (P < 0.001). No pregnancy was achieved in a patient with an antral follicle number of less than five (17 cases). CONCLUSIONS: Age-related changes in antral follicle count significantly predicted the dominant follicle count and the pregnancy outcome. In women with antral follicle counts of less than five or who are older than 35 years, the application of COH/IUI may not be indicated.

Age Factors↗

Production of lambs of predetermined sex after the insemination of ewes with low numbers of frozen-thawed sorted X- or Y-chromosome-bearing spermatozoa.

The fertilizing ability of sex-sorted frozen-thawed ram spermatozoa was assessed after insemination of mature Merino ewes at a synchronized oestrus. Ewes were inseminated into the uterus or utero-tubal junction (UTJ) with a total of 140 x 10(6) unsorted (control) or 2-4 x 10(6) sorted (X or Y) frozen-thawed ram spermatozoa 54 to 57 hours after removal of progestagen-impregnated pessaries and an injection of 400 IU of pregnant mare serum gonadotrophin (Folligon, Intervet). The spermatozoa were separated into X- and Y-chromosome-bearing spermatozoa after analysis with a modified high-speed cell sorter (SX MoFlo). The number of ewes pregnant after insemination with unsorted frozen-thawed spermatozoa was significantly higher (26/48; 54.3%) than for ewes inseminated with either X- (12/48; 25.0%) or Y-sorted spermatozoa (7/48; 14.6%) (P<0.05). Seventeen of the eighteen lambs produced by ewes inseminated with X-sorted spermatozoa were female (94.4%) and 8/8 lambs from ewes inseminated with Y-sorted spermatozoa were male (100%). The sex ratio of the lambs born to ewes inseminated with sex-sorted spermatozoa was significantly skewed from the 51.3% male and 48.7% female ratio in the control group (P<0.05). This study showed, for the first time, that lambs of predicted sex can be produced after insemination with low numbers of sex-sorted cryopreserved ram spermatozoa.

Abortion, Veterinary↗

Abnormal sex ratios in human populations: causes and consequences.

In the absence of manipulation, both the sex ratio at birth and the population sex ratio are remarkably constant in human populations. Small alterations do occur naturally; for example, a small excess of male births has been reported to occur during and after war. The tradition of son preference, however, has distorted these natural sex ratios in large parts of Asia and North Africa. This son preference is manifest in sex-selective abortion and in discrimination in care practices for girls, both of which lead to higher female mortality. Differential gender mortality has been a documented problem for decades and led to reports in the early 1990s of 100 million "missing women" across the developing world. Since that time, improved health care and conditions for women have resulted in reductions in female mortality, but these advances have now been offset by a huge increase in the use of sex-selective abortion, which became available in the mid-1980s. Largely as a result of this practice, there are now an estimated 80 million missing females in India and China alone. The large cohorts of "surplus" males now reaching adulthood are predominantly of low socioeconomic class, and concerns have been expressed that their lack of marriageability, and consequent marginalization in society, may lead to antisocial behavior and violence, threatening societal stability and security. Measures to reduce sex selection must include strict enforcement of existing legislation, the ensuring of equal rights for women, and public awareness campaigns about the dangers of gender imbalance.

Abortion, Induced↗

Missing girls and son preference in rural India: looking beyond popular myth.

Survival chances of girls in parts of South and East Asia have been adverse. Female foeticide, infanticide, abandonment, out-adoption, under-reporting of female births, and selective neglect of girls leading to higher death rates, have contributed to this adversity. Here, I reflect on an observed skewed sex ratio at birth in rural West Bengal, and discuss female foeticide, infanticide, son preference, and abortion. More boys were recorded at birth, and the majority of women desired sons. Trajectories of selective neglect of and discrimination against daughters have been researched extensively, but the related issues of female foeticide and infanticide have been less examined.

Abortion, Legal↗

Sex selection technology utilization: further implications for sex ratio imbalance.

A survey of 242 undergraduates assessed attitudes toward use of sex selection technology and the choice of sex of first- and second-born offspring among potential users. Of our sample, 31 per cent endorsed use of sex selection technology, with the small subsample of nonwhites more accepting of utilization than were whites. There was a significant preference for first-born sons among all potential users, but nonwhites indicated a stronger preference than did whites. Students from rural areas were more desirous of boys than were urban residents. The desire for gender balance within the family documented in earlier studies did not manifest itself. Choice of gender of second child was independent of preference for first-born, with 54 per cent of the potential users desiring sons as both first and second children.

Female↗

Albumin gradients do not enrich Y-bearing human spermatozoa.

The aim of this study was to evaluate objectively whether or not discontinuous albumin gradients enrich the proportion of Y-bearing human sperm. A blinded, collaborative trial design was employed whereby a licensed centre prepared the sperm fractions using licensed procedures, coded the sperm slides and then sent them to an independent laboratory for determination of the X:Y ratio in each sperm fraction using X and Y chromosome-specific probes and double label fluorescence in-situ hybridization (FISH). The identification codes and FISH results were collated by an independent third observer. Two albumin gradient methods which are currently used by licensed centres for male sex pre-selection, protocol 3 and modified protocol 3, were tested. Essentially the same results were obtained for the two methods. Highly motile sperm fractions were recovered from the albumin gradients, and the recoveries of motile spermatozoa (1.3-8.5%) were within the optimal range reported to produce maximal enrichment of Y-bearing spermatozoa. FISH analysis, however, revealed no enrichment for Y-bearing spermatozoa with either method, and the overall X:Y ratios were not significantly different from 1.0. Some samples showed marginal enrichment of Y-bearing spermaotozoa, whereas others showed marginal enrichment of X-bearing spermaotozoa. In conclusion, this collaborative study has demonstrated that the protocol 3 and modified protocol 3 albumin gradient procedures do not enrich Y-bearing spermatozoa. The clinical use of albumin gradients for male sex preselection should be reconsidered in the light of this and other evidence.

Double-Blind Method↗

Female sex selection using clomiphene citrate and albumin separation of human sperm.

BACKGROUND: This study was undertaken to assess whether the use of clomiphene citrate in conjunction with albumin-separated sperm would alter the sex ratio (expressed as the proportion of males) towards females and, if so, whether this skewing was due solely to the induction of ovulation. METHODS: The sex ratios of 184 single and 42 twin births at five assisted reproduction biology clinics were determined. The normal approximation to the binomial distribution was used to determine significant differences between these sex ratios and the established sex ratios for single, twin and combined (single and twin) non- and ovulation-induced births. RESULTS: The non-ovulation-induced sex ratios for singletons (51.4%) and twins (50.2%) were greater than the treatment singleton (27.7%; P < 0.001) and twin (33.3%; P < 0.01) sex ratios respectively. Correspondingly, the non-induced sex ratio for combined births (51.4%) was greater than the treatment sex ratio (28.8%; P < 0.001). The previously established induced singleton and twin sex ratios (48.1%) were lower than the non-induced sex ratio (51.4%), but higher than the treatment singleton (27.7%; P < 0.001) or twin (33.3%; P < 0.03) sex ratios. The ovulation-induced combined ratio (48.1%) was less than the non-induced combined (51.4%) sex ratio, although greater than the treatment combined sex ratio (28.8%; P < 0.001). CONCLUSION: Clomiphene citrate in conjunction with albumin-separated sperm decreased the sex ratio; a reduction that was not exclusively due to induction of ovulation.

Cell Separation↗

Preconception sex selection for non-medical reasons:a representative survey from Germany.

BACKGROUND: Preconception sex selection for non-medical reasons raises serious moral, legal and social issues. The main concern is based on the assumption that a freely available service for sex selection will distort the natural sex ratio and lead to a severe gender imbalance. However, for a severe gender imbalance to happen, at least two conditions have to be met. First, there must be a significant preference for children of a particular sex, and second, there must be a considerable demand for preconception sex selection. To ascertain whether or not these two conditions are met, we have conducted a survey in Germany. METHODS: As a representative sample of the German population, 1094 men and women aged 18-45 years were asked about their gender preferences and whether or not they could imagine selecting the sex of their children through flow cytometric separation of X- and Y-bearing sperm followed by intrauterine insemination. RESULTS: 58% of respondents stated that they do not care about the sex of their offspring. 30% wish to have a family with an equal number of boys and girls. 4% would like to have more boys than girls, 3% more girls than boys, 1% only boys and 1% only girls. For first-borns, however, there is still a preference for boys over girls. While 75.6% claimed to have no gender preference, 14.2% would like their first child to be a boy and 10.1% would like their first child to be a girl. Whereas 6% could imagine taking advantage of preconception sex selection, 92% found this to be out of the question. Even in the hypothetical case that a medication for sex selection were ever to become available, 90% stated that they would not want to use it. CONCLUSION: Given that a majority does not seem to care about the sex of their offspring and only a minority seem to be willing to select the sex of their children, a freely available service for preconception sex selection for non-medical reasons is rather unlikely to cause a severe gender imbalance in Germany.

Adult↗

Sex predetermination and the ethics of sex selection.

At present there appear to be two main categories of problems involved in the ethics of sex selection. The first has to do with the status of the embryo, and the second has to do with the social consequences of making sex selection widely available. However, these may not be the only issues. There is growing evidence from evolutionary psychology and biology, which suggests that the sex of the offspring in mammals may not, after all, be a matter of chance. Instead, sex allocation in mammals may be the result of a finely tuned adaptive process involving the current suitability of a mother to conceive an offspring of a particular sex. If so, we need to know more about this process before embarking on a social policy that could have disadvantageous outcomes for children, their parents and society as a whole.

Animals↗