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1.
Cutas D 《Bioethics》2007,21(8):458-463
The paper explores the ethics of post-menopausal motherhood by looking at the case of Adriana Iliescu, the oldest woman ever to have given birth (so far). To this end, I will approach the three most common objections brought against the mother and/or against the team of healthcare professionals who made it happen: the age of the mother, the fact that she is single, the appropriateness of her motivation and of that of the medical team.  相似文献   

2.
Bringing gender and kinship studies together with an anthropology of religion, in this article I demonstrate how urban Greek couples and clinical practitioners in the middle 1990s proceeded with in vitro fertilization (IVF) in the absence of government regulations, and did so with reference to cultural beliefs and social relations consistent with Greek Orthodox religious practice. Drawing on ethnographic observations at an Athens IVF clinic as well as on interviews with former patients, I argue that Athenian women, in particular, engage IVF as a kind of spiritual kin work, normalizing the use of medical techniques with reference to ideologies of motherhood that treat it as a woman’s moral achievement and as a source of womanly suffering. Since the period of ethnographic research described here, and despite disapproval of the Greek Orthodox Church, legislation regulating the use of IVF and other methods of medically assisted reproduction has become law. This article reconciles how the Church can officially reject medically assisted means of reproduction that Athenian users have normalized with reference to spiritual beliefs and practices.  相似文献   

3.
摘要 目的:探究不同病变类型子宫内膜异位症(Endometriosis,EMs)对卵巢储备功能及辅助生殖技术结果的影响。方法:选择2018年1月-2021年1月于承德医学院附属医院妇产科就诊的EMs合并不孕症患者188例作为研究对象,纳入实验组,另随机选择同期单纯男性因素不孕妇女160例作为对照。对符合临床标准的患者行IVF-ET治疗,计算其胚胎种植率、临床妊娠率、活产率,对患者血清抗苗勒氏管激素(AWH)、卵泡刺激素(FSH)、黄体生成素(LH)、窦卵泡素(AFC)水平进行检测。结果:r-AFS III期、IV期AWH水平显著低于对照组,差异具有统计学意义(t=7.00、11.86,P均<0.05);II期、III期、IV期AFC计数显著低于对照组,差异具有统计学意义(t=4.50、8.49、9.06,P均<0.05)。r-AFS分期III期、IV期患者种植率、临床妊娠率、活产率显著低于对照组(x2=4.04、4.72、10.46、8.80、11.32、12.21,P均<0.05)。多因素logistic回归分析结果表明,r-AFS分期III期、IV期是IVF-ET不良结局的主要危险因素,具有统计学意义(P<0.05)。结论:III/IV期EMs可在一定程度上降低妇女的卵巢储备功能,同时降低了IVF-ET过程中的种植率及临床妊娠率,从而对其妊娠结局产生不良的影响。  相似文献   

4.
Durrant BS 《Theriogenology》2009,71(1):113-122
Artificial insemination (AI) is the least invasive assisted reproductive technology, and is therefore of great interest to breeders of companion animals, non-domestic, and endangered species (CANDES). This most fundamental artificial breeding technique circumvents physical or behavioral impediments to natural mating and provides the means for genetic exchange between populations without transfer of live animals. In addition, because oocytes grow, mature and are fertilized in vivo and embryos are not subjected to in vitro culture conditions, AI eliminates the epigenetic effects on the female gamete that are inherent in more invasive assisted reproductive technologies. Although the management of CANDES differs significantly from current livestock husbandry practices, the cattle industry is a powerful example of the potential for AI to enhance the genetic health and sustainability of animal populations. Ultimately, successful AI requires sperm of adequate quality and quantity, oocytes that have attained nuclear maturation and cytoplasmic competence, operational gamete transport systems, accurate timing, and proper placement of sperm in the female reproductive tract. Increased understanding of semen collection, evaluation and preservation techniques, estrus synchronization and superovulation, estrus and ovulation detection, and insemination instrumentation is needed for each CANDES before AI success rates will approach those of the livestock industry. Concentrated, collaborative research in these areas must be encouraged among private breeders, universities and zoological institutions to realize the full potential of AI in the management of CANDES.  相似文献   

5.
    
Research on embryo donation and receipt continues to grow, highlighting how specific national contexts shape views and experiences. The present article reports on a qualitative study on embryo donation and receipt in Australia. Interviews were conducted with 15 participants: embryo donors and those seeking to donate (6), embryo recipients and those seeking donors (3), people with embryos in storage or previously in storage (5), and egg donors where resulting embryos were donated to a third party (1). A deductive thematic analysis identified four key themes: understandings of embryos as cells, potential children, and/or children; a focus on relationships between “siblings”; importance of language and “family words” in discussing relationships; and extended family members having difficulty understanding the concept of embryo donation. The article concludes with a consideration of the implications of the findings in terms of the practice of embryo donation and the policies that surround it.  相似文献   

6.
This paper explores whether egg donation could still be ethically justified if in vitro gametogenesis (IVG) became reliable and safe. In order to do this, issues and concerns that might inform a patient’s reasoning in choosing to use donor eggs instead of IVG are explored and assessed. It is concluded that egg donation would only be ethically justified in a narrow range of special cases given the (hypothetical) availability of IVG treatment and, further, that egg donation could itself be replaced by donation through IVG techniques. Two possible criticisms of this position are then considered: Ones based on respect for patient wishes, and on loss of donor benefit. It is concluded that whilst neither argument constitutes a strong enough reason to continue with programmes of egg donation, egg‐sharing programmes could still be permitted come the advent of IVG; these could then provide a morally acceptable source of “natural” donor eggs.  相似文献   

7.
    
JASON K.M. HANNA 《Bioethics》2010,24(7):341-347
Many critics of commercial surrogate motherhood argue that it violates the rights of children. In this paper, I respond to several versions of this objection. The most common version claims that surrogacy involves child‐selling. I argue that while proponents of surrogacy have generally failed to provide an adequate response to this objection, it can be overcome. After showing that the two most prominent arguments for the child‐selling objection fail, I explain how the commissioning couple can acquire parental rights by paying the surrogate only for her reproductive labor. My explanation appeals to the idea that parental rights are acquired by those who have claims over the reproductive labor that produces the child, not necessarily by those who actually perform the labor. This account clarifies how commercial surrogacy differs from commercial adoption. In the final section of the paper, I consider and reject three further child‐based objections to commercial surrogacy: that it establishes a market in children's attributes, that it requires courts to stray from the best interests standard in determining custodial rights, and that it requires the surrogate to neglect her parental responsibilities. Since each of these objections fails, children's rights probably do not pose an obstacle to the acceptability of commercial surrogacy arrangements.  相似文献   

8.
    
Sexual conflicts often arise between mating partners because each sex tries to maximize its own reproductive success. One major male strategy to influence a partner's resource allocation is the transfer of accessory gland proteins. This has been shown to occur in simultaneous hermaphrodites as well as in organisms with separate sexes. Although accessory gland proteins affect the investment of resources in both male and female function, we here specifically focus on female investment. In the great pond snail, Lymnaea stagnalis, previous studies found that the accessory gland protein ovipostatin reduced female fecundity by suppressing egg laying in the partner in the short term (days). To investigate whether this reduction in egg laying is a commonly found effect of mating in freshwater snails, we compared egg output for evidence of suppression in isolated and paired snails of eight pulmonate species. Furthermore, we determined whether the suppression of egg laying caused a shift in resource allocation to the eggs. We found that in five of the eight species egg laying was suppressed, with fewer and lighter egg masses being laid when they had access to a mating partner. In mated pairs of L. stagnalis and Biomphalaria alexandrina, allocation of resources to the eggs was altered in opposite ways: individuals of L. stagnalis laid fewer but larger and heavier eggs; individuals of B. alexandrina laid smaller and lighter eggs, with no change in egg numbers. Such changes in the female function are most likely the result of combined effects of receiving accessory gland proteins, and the cost of mating in both male and female roles. Thus, effects of the maternal environment, including the receipt of accessory gland proteins, on offspring investment are not restricted to species with separate sexes.  相似文献   

9.
    
In this study, effective gamete concentrations, egg viability, and fertilization volumes were evaluated for Haliotis midae (L.). Sperm concentrations between 5?×?103 and 5?×?104?mL?1 (p?>?0.05) consistently resulted in high hatch-out rates (96?±?1%). At concentrations higher than 5?×?105?mL?1, hatch-out rates decreased to 69?±?7% (p??1 resulted in high fertilization rates, with 50?eggs?mL?1 being the ideal concentration for fertilization in H. midae. Egg viability was consistently high up to 100?min post-spawning, with a decrease in hatch-out success, when eggs were fertilized 120?min post-spawning. Fertilization volumes did not affect successful hatch-out. The results from this study can be implemented by South African abalone farms to increase hatch-out rates and subsequent culture. It can also be used as basis for the development of fertilization protocols in other marine invertebrate species.  相似文献   

10.
Successful cryopreservation of sperm and the maintenance of a sperm-based genome resource bank have been identified as priorities for the recovery of the endangered red wolf (Canis rufus). The objectives were to improve sperm processing and to determine the relative timing of damage to red wolf sperm during freezing and thawing. Fresh ejaculates (n=37) from adult red wolves (n=15, aged 2-13 y) were collected via electroejaculation and subjected to cooling, freezing and thawing in four TRIS-egg-yolk extender treatments varying in osmolality ( approximately 305 mOsm versus approximately 350 mOsm) and egg-yolk composition (0.8 microm-filtered versus unfiltered). Ejaculates were evaluated for sperm percentage motility, forward progressive motion, and morphological characteristics immediately upon collection and following extension, cooling (prior to freezing) and thawing. Although no single treatment consistently produced superior results, sperm suspended in approximately 305 mOsm extenders exhibited slight losses in motility post-thawing (13 and 7%). Also, sperm suspended in approximately 350 mOsm extenders tended to have slower rates of decline in motility in vitro post-thawing than those stored in approximately 305 mOsm extenders (P=0.55). Finally, extenders incorporating unfiltered egg yolk exhibited a slightly larger ratio of absent to partial acrosomes than did sperm frozen in extenders prepared with clarified egg yolk. For approximately 350 mOsm extenders, most motility loss occurred during the cooling rather than freezing and thawing. In conclusion, these data contribute to knowledge regarding cryopreservation of red wolf sperm.  相似文献   

11.
12.
The estrous cycle length in the white rhinoceros (Ceratotherium simum) is either 4 or 10 wk. The cause(s) for this variation as well as the poor fertility rate in captivity remains under debate in this species. Most captive adult white rhinoceros undergo long anovulatory periods without luteal activity which are considered a major reason for their low reproductive rate. In this study, the synthetic progestin chlormadinone acetate (CMA) was tested in combination with hCG or the GnRH analogue deslorelin for its efficiency to induce ovulation in fourteen females without luteal activity and in three, regular cycling females. HCG (N = 12), injectable GnRH analogue (N = 8) and GnRH analogue implants (N = 15) were given to induce ovulation after CMA treatment. Treatment success was determined using both transrectal ultrasonography and progesterone metabolite EIA analysis. A preovulatory sized follicle (3.5 ± 0.1 cm) or a corpus luteum (5.1 ± 0.7) was present on the ovary one day after induction in 93.1% of the treatments. Despite this high rate of ovarian response, ovulation rate differed between the study groups. The ovulation rate for hCG, injectable GnRH analogue and GnRH analogue implants was 66.7%, 62.5% and 93.3%, respectively. Ovulation rate in cyclic females treated with GnRH implants was 100% (6/6) compared with 89% (8/9) in females without luteal activity receiving the same treatment. The length of the estrous cycle when induced with hCG was 4 wk (85.7%). The estrous cycle when induced with GnRH analogue was predominantly 10 wk long. Two females without luteal activity treated with GnRH became pregnant. In conclusion, CMA in combination with GnRH analogue implants was highly effective to induce ovulation in white rhinoceroses and thus can contribute to efforts aimed at increasing natural mating and reproductive rates in the captive white rhinoceros population.  相似文献   

13.
This study aimed to establish artificial insemination (AI) protocols to predictably initiate pregnancy during the breeding season in the European brown hare (EBH) (Lepus europaeus PALLAS, 1778). Semen was collected from seven captive and eight free-ranging males by means of electroejaculation. Semen from the free-ranging males was cryopreserved using directional freezing. Total motility/integrity of fresh and frozen-thawed semen was 91.6%/87.7% and 46.9%/53.8%, respectively. Ovulation was induced in ultrasonographically preselected females using a gonadotropin-releasing hormone analogue. Each female was inseminated with 1 mL fresh (Group A, n = 16) or frozen-thawed semen (Group B, n = 9) at a concentration of 100 × 106 spermatozoa/mL. The use of ultrasonography (10 to 22 MHz) confirmed the intracervical semen deposit, the success of artificial ovulation induction (formation of postovulatory corpus luteum), and permitted the monitoring of individual pregnancies. Although sperm motility/integrity was significantly different between groups, no significant difference was detected in conception rates (A, 87.50%; B, 77.78%). Because of embryonic resorption, there was a slight difference in fertility rate between groups (A, 62.5%; B, 77.78%). Overall, AI in captive EBH using fresh and frozen-thawed semen achieved successful fertility rates. Long-term cryopreserved semen was used to bring new genetic material from the wild into a genetically limited captive population without extensive animal transport. Therefore, AI has the potential to enhance breeding programs for EBH especially when cryopreserved semen from wild donors is used.  相似文献   

14.
Yamasinaium noduligerum is a Japanese fungivorous millipede that is usually found on decaying logs fallen on the forest floor. Here we present observations on paternal egg-brooding behavior in this species. At the end of May to early June, we found males with eggs on the bark of the underside of fallen decaying logs and in old burrows and galleries excavated by wood-dwelling insects under the bark of the logs. The males showed a typical brooding posture where they curl the anterior part of the body around the egg mass. The egg masses contained, on average, 30.2 ± 13.7 (SD) eggs. The brooding males showed no aggressive responses when disturbed.  相似文献   

15.
This paper aims to evoke an alternative viewpoint on surrogacy, moving beyond popular Western feminist beliefs on the practice, by introducing the history and current context of East Asian surrogacy. To elaborate a different cultural perspective on surrogacy, this paper first introduces the East Asian history of contract pregnancy systems, prior to the emergence of the American invention of ‘modern’ surrogacy practice. Then, it examines Japanese mass media portrayals of cross-border surrogacy in which white women have become ‘convenient’ entities. The results of the analysis show how Japanese culture has adopted a rhetoric about the use of white women as convenient surrogate mothers in the global commercial surrogacy market. An essential aspect of surrogacy is the premise that a woman’s reproductive function should be accessible to others. Past discussions among feminists have neglected this important point. Moreover, they share the assumption that white surrogacy clients are exploiters, who take advantage of women of colour as surrogate mothers. The current situation in Asia flips this perspective—with white women regarded as easier targets for exploitation by wealthy people of colour. For Asian clients, Westerners can be easily regarded as ‘others’ whom they can use for their reproductive needs. In today's globalized era, the surrogacy industry is no longer for affluent Westerners only. Considering this change, it is crucial to discuss surrogacy issues by reconstructing feminist perspectives with a globalized view, to help protect women’s bodies, regardless of nationality, ethnicity, skin colour, or religion.  相似文献   

16.
Artificial insemination in deer and non-domestic bovids   总被引:1,自引:0,他引:1  
Artificial insemination technology has revolutionized the domestic cattle breeding industry and allowed for the dissemination of valuable genetics worldwide. This technology has been adapted for use in many other taxa for the conservation of threatened and endangered species, but its use for the genetic management of small populations of deer, antelope and other non-domestic bovids has met numerous challenges and limited success. In practice, adaptation of domestic bovine AI protocols to other artiodactylids for genetic management has been limited by: (1) a lack of understanding of species-specific reproductive characteristics; (2) the inability to minimize handling stress; (3) pregnancy losses; and (4) regulatory challenges in semen importation. To date, AI protocols have been developed for seven species of cervid and 14 species of non-domestic bovids; recent developments in this technology has allowed greater use of AI for dissemination of genetics in farmed deer species. However, despite decades of research in the use of assisted reproduction for the conservation of antelope and other non-domestic bovids, even this simplest technique has not been used repeatedly for genetic management.  相似文献   

17.
    
Many psittacine species are threatened in the wild and also rare in captivity. Therefore, successful conservation and breeding programs are important to save these species. Unfortunately, clutches in conservation programs are frequently infertile. Semen evaluation is beneficial to investigate the causes of infertility and is advisable before artificial insemination (AI). In this study, we analyzed the semen of cockatiels (Nymphicus hollandicus) using two different methods and investigated different insemination dosages for AI. Cockatiels (n = 30) were divided into two groups (group A: nine males; group B: six males). The males in group B were endoscopically sterilized, whereas the males in group A were used as semen donors. In the first part of the study, the semen of males in group A was evaluated by semen analysis. Semen samples were collected by the massage technique and examined using a conventional light microscope and a computer-assisted semen analyzer for comparison. Results demonstrated that the evaluations of motility, progressive motility, and sperm concentration, but not of live/dead ratio, correlated strongly for both methods. However, the results for sperm concentration, progressive motility, and live/dead ratio differed significantly. In the second part of our study, the volume and quantity of spermatozoa of the semen samples were adjusted and used for AI of females of group B. Intravaginal insemination with 250,000 spermatozoa resulted in five of 17 (29%) eggs fertilized; however, intracloacal insemination resulted in only four of 57 (7%) eggs fertilized at 232,000 and 250,000 spermatozoa but none at higher or lower dosages.  相似文献   

18.
本研究首次从东北虎(Panthea tigris altaica)脑垂体提取总RNA,利用RT-PCR技术扩增出东北虎垂体促性腺激素α亚基,促卵泡激素(FSH)β亚基和促黄体激素(LH)β亚基的编码区序列,并进行克隆,测序和比较分析。结果表明,其α亚基,FSHβ亚基,LHβ亚基基因的开放阅读框分别为363bp,390bp和420bp,分别编码120,129和142氨基酸的前体蛋白。与已发表的人,牛,绵羊,猪,大鼠,小鼠等物种相应序列比较,无论在核苷酸水平,还是在氨基酸水平都显示出较高的同源性(64.7%-96.6%),其中与猪的同源性最高(86%-96.6%)。东北虎的基因序列还具有其明显的特异性,首次发现LHβ亚基cDNA编码的前体蛋白在信号肽部分比其它物种相应序列多一个亮氨酸残基(Leu)。  相似文献   

19.
    
The Cephaloscyllium ventriosum shark is present in the artisanal fisheries of elasmobranchs on the western coast of Baja California Sur, Mexico. The main characteristics of the sexual maturation of this species based on individuals captured from off north-west Mexico in 2013–2016 are described. The size at maturity of this species was determined for the first time (total length 82 cm for females and 76 cm for males). Most females had one egg case per one uterus, and two per one uterus was an isolated event of low incidence. From the histological analysis of females, it was possible to show sperm storage in the oviducal gland. Fully developed sperm in immature organisms were identified in the testes. The main indicator of the maturity stage of males and their mating activity is the clasper. The present study provides evidence for a reliable estimation of the sexual maturity of these organisms, demonstrating the need for the combination of macroscopic and microscopic methods.  相似文献   

20.
山地麻蜥的雌性繁殖和孵出幼体特征   总被引:2,自引:0,他引:2  
山地麻蜥年产多窝卵。窝卵数、窝卵重和卵重与雌体体长呈正相关,卵重与窝卵数无关。窝卵数、窝卵重和卵重不存在明显的季节变化。卵长径与卵短径呈正相关,卵长径、卵短径与窝卵数无关。雌体通过增加窝卵数和卵大小增加繁殖输出。孵出幼体的体重、体长、尾长、躯干干重、刺余卵黄不存在季节差异,但5月份孵出幼体的脂肪体高于4月份。  相似文献   

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