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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Assisted reproductive technology | 2/5 | https://en.wikipedia.org/wiki/Assisted_reproductive_technology | reference | science, encyclopedia | 2026-05-05T14:56:25.441832+00:00 | kb-cron |
=== Pre-implantation genetic diagnosis === A pre-implantation genetic diagnosis procedure may be conducted on embryos before implantation (as a form of embryo profiling), and sometimes even of oocytes before fertilization. PGD is considered similar to prenatal diagnosis. PGD is an adjunct to ART procedures and requires in vitro fertilization to obtain oocytes or embryos for evaluation. Embryos are generally obtained through blastomere or blastocyst biopsy. The latter technique has proved to be less deleterious for the embryo; it is advisable to perform the biopsy around day 5 or 6 of development. Sex selection is the attempt to control the sex of offspring to achieve a desired sex in case of X chromosome-linked diseases. It can be accomplished in several ways, both pre- and post-implantation of an embryo, as well as at birth. Pre-implantation techniques include PGD, but also sperm sorting.
=== Others === Other assisted reproduction techniques include:
Mitochondrial replacement therapy (MRT, sometimes called mitochondrial donation) is the replacement of mitochondria in one or more cells to prevent or ameliorate disease. MRT originated as a special form of IVF in which some or all of the future baby's mitochondrial DNA comes from a third party. This technique is used in cases when mothers carry genes for mitochondrial diseases. The therapy is approved for use in the United Kingdom. In gamete intrafallopian transfer (GIFT), a mixture of sperm and eggs is placed directly into a woman's fallopian tubes using laparoscopy following a transvaginal ovum retrieval. Reproductive surgery, treating e.g. fallopian tube obstruction and vas deferens obstruction, or reversing a vasectomy by a reverse vasectomy. In surgical sperm retrieval (SSR), the reproductive urologist obtains sperm from the vas deferens, epididymis, or directly from the testis in a short outpatient procedure. By cryopreservation, eggs, sperm, and reproductive tissue can be preserved for later IVF.
== Risks == The majority of IVF-conceived infants do not have birth defects. However, some studies have suggested that assisted reproductive technology is associated with an increased risk of birth defects. Artificial reproductive technology is becoming more available. Early studies suggest that there could be an increased risk for medical complications with both the mother and baby. Some of these include low birth weight, placental insufficiency, chromosomal disorders, preterm deliveries, gestational diabetes, and pre-eclampsia (Aiken and Brockelsby). In the largest U.S. study, which used data from a statewide registry of birth defects, 6.2% of IVF-conceived children had major defects, as compared with 4.4% of naturally conceived children matched for maternal age and other factors (odds ratio, 1.3; 95% confidence interval, 1.00 to 1.67). ART carries with it a risk for heterotopic pregnancy (simultaneous intrauterine and extrauterine pregnancy). The main risks are:
Genetic disorders Low birth weight. In IVF and ICSI, a risk factor is the decreased expression of proteins in energy metabolism; Ferritin light chain and ATP5A1. Preterm birth. Low birth weight and preterm birth are strongly associated with many health problems, such as visual impairment and cerebral palsy. Children born after IVF are roughly twice as likely to have cerebral palsy. Sperm donation is an exception, with a birth defect rate of almost a fifth compared to the general population. It may be explained by the fact that sperm banks accept only people with high sperm count. Germ cells of the mouse normally have a frequency of spontaneous point mutations that is 5 to 10-fold lower than that in somatic cells from the same individual. This low frequency in the germline leads to embryos that have a low frequency of point mutations in the next generation. No significant differences were observed in the frequency or spectrum of mutations between naturally conceived fetuses and assisted-conception fetuses. This suggests that with respect to the maintenance of genetic integrity, assisted conception is safe. Current data indicate little or no increased risk for postpartum depression among women who use ART. Socio-ethical considerations of advanced parental age: The increasing use of ART by older individuals, facilitated by techniques such as elective oocyte cryopreservation (commonly known as "social freezing"), raises significant socio-ethical questions. While often framed as a tool for enhancing reproductive autonomy by allowing individuals to delay childbearing for personal or professional reasons, this practice is subject to ethical debate. Proponents argue it empowers women by providing greater biological control. However, critics warn it may medicalize a social problem—the difficulty of balancing career and family—and create pressure for women to use this technology. Furthermore, it presents a potential ethical challenge regarding the welfare of the future child, as some studies suggest that children of significantly older parents may face unique psychosocial challenges, including a higher probability of losing parents at a younger age. This has sparked complex debates in clinical ethics about the balance between reproductive rights and the potential interests of the child. Study results indicate that ART can affect both women's and men's sexual health negatively. Usage of assisted reproductive technology, including ovarian stimulation and in vitro fertilization, has been associated with an increased overall risk of childhood cancer in the offspring, which may be caused by the same original disease or condition that caused the infertility or subfertility in the mother or father. That said, in a landmark paper by Jacques Balayla et al., it was determined that infants born after ART have similar neurodevelopment to infants born after natural conception. ART may also pose risks to the mother. A large US database study compared pregnancy outcomes among 106,000 assisted conception pregnancies with 34 million natural conception pregnancies. It found that assisted conception pregnancies were associated with an increased risk of cardiovascular diseases, including acute kidney injury and arrhythmia. Assisted conception pregnancies were also associated with a higher risk of caesarean delivery and premature birth. In theory, ART can solve almost all reproductive problems, except for severe pathology or the absence of a uterus (or womb), using specific gamete or embryo donation techniques. However, this does not mean that all women can be treated with assisted reproductive techniques, or that all women who are treated will achieve pregnancy.