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Does Personhood Begin at Conception?
Published in Christopher Kaczor, The Ethics of Abortion, 2023
This is a biological question, and we could quote here, page after page, numerous biologists, scientists, and physicians who have provided clear answers to this question. In the interest of space, let's consider only three texts (noted earlier by Lee 1996):The formation, maturation, and meeting of a male and female sex cell are all preliminary to their actual union into a combined cell, or zygote, which definitely marks the beginning of a new individual. This penetration of the ovum by spermatozoon, and the coming together and pooling of their respective nuclei, constitutes the process of fertilization.(Arey 1974, p. 55)the fertilization of an ovum by a sperm. The expression “fertilized ovum” refers to the zygote.(Moore 1983, p. 9)Embryonic life commences with fertilization, and hence the beginning of that process may be taken as the point of departure of stage I.(Larsen 1993, p. 19)
Endocrine Disease
Published in John S. Axford, Chris A. O'Callaghan, Medicine for Finals and Beyond, 2023
Treatment:Hormone treatment: simple, but patients may require several consultations before understanding the full implications for fertilityOvum donation: donor egg + partner's sperm
The Many Faces of Neoplasia
Published in Jeremy R. Jass, Understanding Pathology, 2020
The majority of cancers may be ascribed to one of the three cancer types: carcinoma, sarcoma and lymphoma. This classification has an embryological basis. When an ovum is fertilised by a sperm, the result is a single cell or zygote (from the Greek word meaning joined together). The zygote carries the potential to form all the cells of the body. At first this totipotential cell divides to form two, then four, then eight cells and so on. At this early stage the ball of cells may be disaggregated and could in theory form a clone of two, four, eight or sixteen identical individuals. The embryo starts to form when groups of cells become committed to a particular line of tissue differentiation, of which there are three major types. Ectoderm forms the skin and nervous system, endoderm forms the epithelial lining of internal hollow organs (e.g. gut) and associated glandular organs (e.g. liver and pancreas), and mesoderm forms all the rest (muscle, bone, bone marrow, cartilage, lymphoid system and connective tissue). As a general rule carcinomas arise from ectoderm or endoderm, whereas sarcomas and lymphomas arise from mesoderm.
Human Germline Genome Editing: On the Nature of Our Reasons to Genome Edit
Published in The American Journal of Bioethics, 2022
Douglas and DeVolder’s argument is fascinating and well-made. However, it assumes that it would be ethically defensible to genome edit, and then to proceed to implant, a single, already existing, embryo, which, as I have argued here, is highly unlikely for the foreseeable future. In all likelihood, genome editing will involve creating and editing multiple embryos before selecting the “best child possible.” Moreover, where prospective parents are motivated by a desire to enhance their children rather than to avoid a genetic disorder, which, I have suggested, is a more plausible motivation for the project in the longer term, the decision to genome edit will almost certainly be identity affecting, as a couple (or individual) will usually make it before they have created any embryos and the process itself will, at the very least, alter the timing of conception. This is itself usually sufficient to bring it about that a different sperm fertilizes the ovum, with the consequence that a different person is born (Parfit 1984, 351–352). Thus, if we include the decision to edit in our deliberations about the relevant counterfactual for assessing harm or benefit, then genome editing will be identity affecting and the children born as a result of the procedure will neither be harmed or benefited by it.
A case report on recurrent partial moles in three consecutive pregnancies
Published in Journal of Obstetrics and Gynaecology, 2022
Prashida Guha Sarkar, Saroj Dalmia, Pinky Khatri
Hydatidiform moles are abnormal conceptions, occurring in about one in 500–1000 pregnancies (Seckl et al. 2000). Complete moles are diploid and androgenic in origin and have no evidence of foetal tissue. Most (90%) arise secondarily to fertilisation of an empty ovum with duplication of a haploid sperm. In contrast, partial moles show evidence of foetal tissue and are triploid in origin, containing one set of maternal haploid chromosomes and two sets of paternal haploid chromosomes, derived from dispermic fertilisation of an ovum (90%). On histology, a PM pregnancy shows presence of foetal tissue, focal hydropic change to the villi and some excess trophoblast proliferation. Ploidy status and immunohistochemistry staining for p57, a paternally imprinted gene, help in distinguishing partial from CM pregnancies (Tham et al. 2003).
Progress in understanding and management of premature ovarian insufficiency
Published in Climacteric, 2021
One of the most distressing effects of POI is the associated subfertility [5]. Whilst ovum donation in vitro fertilization remains an effective way to achieve a family in POI, this is not acceptable to a significant proportion of women for personal, ethical and cultural reasons. It is therefore imperative that research into novel approaches for fertility restoration continues in women with POI. The last paper addresses future interventions which might facilitate the use of remaining autologous oocytes and creation of new autologous oocytes. Primordial follicle stimulation and mesenchymal stem cell-based therapeutics appear to be the most promising of the novel techniques but are unlikely to yield routine clinical approaches for a number of years. The authors emphasize that clinical studies with appropriate controls are needed to substantiate preliminary claims of effectiveness of these novel approaches.