The costs and availability of fertility treatment
Ruth Chambers in Fertility Problems, 2018
There is a great variation in the availability, accessibility and range of services of National Health Service (NHS)-funded provision of fertility treatment. The varying selection criteria set by health authorities has the effect that the availability of NHS-funded fertility treatment depends on geographical location and social situation rather than patients' needs. In vitro fertilisation (IVF) was one of the first treatments to be explicitly rationed by the NHS. In 1993, the purchasing plans of six of 114 health authorities in the UK explicitly stated that they would not be buying any IVF or Gamete intra-fallopian transfer (GIFT) treatments for their populations. The differences in outlook were based on diverse interpretations of the relative importance of factors considered in assessing the needs of their local populations. There was a variation in waiting time for assisted conception treatment from up to a year after referral to more than four years after referral.
Assisted Reproduction and Embryo Research
Marc Stauch, Kay Wheat in Text, Cases and Materials on Medical Law and Ethics, 2017
This chapter explores that specific solutions adopted by the law in relation to the key areas of licensed fertility treatment. It focuses on in vitro fertilisation treatment involving the creation of an embryo ex vivo to be implanted in a woman's uterus for gestation. The chapter considers the law on gamete and/or embryo donation as it bears in turn on the interests of the immediate parties to such an enterprise, namely the potential nurturing parents, the gamete donors, and any child who is born as a result. It attempts to the field of assisted reproduction, addresses the additional complexities that arise when third party gamete providers are introduced into the picture by procedures such as Artificial Insemination by Donor ('DI') and egg donation. The chapter also focuses on one area where third party involvement in reproduction has aroused particular controversy, namely, surrogacy, in which a woman makes use of her gestational capacity to carry a child for others.
Genetic Imperatives and Selective Technologies in the Global Landscape
Lauren Jade Martin in Reproductive Tourism in the United States, 2014
This chapter explores the role of genetic thinking within the fertility industry. It begin with a brief overview of how the history of eugenics has shaped reproductive politics in the United States. The chapter explores how this history has also left an imprint on the development of reproductive technologies, imbuing its consumers and producers with ideas about the genetic imperative and the possibilities of genetic determinism and selection. To consider the relationship between attitudes of providers in the United States and popular understandings of genetics that transcend national laws and policy. Whether one uses one's own gametes or that of a donor, the ideologies of genetic determinism and consumer sovereignty converge in these selective technologies. Providers also had a complex relationship with PGD which, unlike egg donation, is used more definitively to diagnose the DNA of embryos to screen out or select for sex or particular genetic conditions.
Gamete membrane dynamics during double fertilization in
Published in Plant Signaling & Behavior, 2013
In the double fertilization of angiosperms, one sperm cell fertilizes an egg cell to produce a zygote, whereas the other sperm cell fertilizes a central cell to give rise to an endosperm. There is little information on gamete membrane dynamics during double fertilization even though the cell surface structure is critical for male and female gamete interactions. In a recent study, we analyzed gamete membrane behavior during double fertilization by live-cell imaging with Arabidopsis gamete membrane marker lines. We observed that the sperm membrane signals occasionally remained at the boundary of the female gametes after gamete fusion. In addition, sperm membrane signals entering the fertilized female gametes were detected. These findings suggested that plasma membrane fusion between male and female gametes occurred with the sperm internal membrane components entering the female gametes, and this was followed by plasmogamy.
Gamete fusion site on the egg cell and autonomous establishment of cell polarity in the zygote
Published in Plant Signaling & Behavior, 2010
Gamete fusion activates the egg in animals and plants, and the gamete fusion site on the zygote might provide a possible cue for zygotic development and/or embryonic patterning. In angiosperms, a zygote generally divides into a two-celled proembryo consisting of an apical and a basal cell with different cell fates. This is a putative step in the formation of the apical–basal axis of the proembryo. We observed the positional relationship between the gamete fusion site and the division plane formed by zygotic cleavage using an in vitro fertilization system with rice gametes. There was no relationship between the gamete fusion site and the division plane leading to the two-celled proembryo. Thus, the gamete fusion site on the rice zygote does not appear to function as a determinant for positioning the zygote division plane, and the zygote apparently possesses autonomous potential to establish cell polarity along the apical–basal axis for its first cleavage.
Gamete mating and fusion in the marine dinoflagellate Scrippsiella sp.
Published in Phycologia, 1989
Gao Xiaoping, John D. Dodge, Jane Lewis
Gamete mating and fusion of Scrippsiella sp. have been studied by light and scanning electron microscopy. When two gametes mate, the transverse flagellum of one gamete migrates out of the girdle and grasps the longitudinal flagellum of the other gamete and then returns to the girdle. Two gametes move together by helical movement of this transverse flagellum over the longitudinal flagellum of the other gamete. Fusion starts when the sulcal regions near the flagellar pores of the gametes contact each other, and then it extends first to the hypothecal regions. The epicones of the gametes fuse later. As fusion proceeds, one of the transverse flagella is lost and the other elongates to surround both gametes. When plasmogamy is completed, a motile zygote (planozygote) is formed which retains two longitudinal flagella and one transverse flagellum. Comparison of this process with that of cell division shows clearly the important differences between them which should help to avoid confusion in the future. The present findings are also compared with those of other dinoflagellate species in which sexual reproduction has been studied, and the similarity between dinoflagellate gamete mating and that of Chlamydomonas is noted.