s Preimplantation Genetic Diagnosis (PGD)
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Preimplantation Genetic Diagnosis (PGD) is mostly performed when a couple has a known risk for genetic disorders, to look for chromosomal abnormalities due to advancing maternal age. The women aged 35 years and older have higher incidence of Down syndrome or early miscarriage.

PGD is a process by which parents may identify and even select genetic characteristics in their child. This is used mostly to prevent susceptibility to disease, birth defects, and handicaps. Commonly, PGD is used to prevent children from being born with autism, Down's syndrome, muscular dystrophy, cystic fibrosis, sickle cell anemia, Alzheimer's disease, and other disorders. When eggs are fertilized outside the body, as they are in IVF, they can be evaluated so that those that are least susceptible to serious disease or genetic complications can be implanted. It should be noted that not all diseases have a genetic component, so signs of the disease's potential to develop later in life may not be present in the embryo stage.

The parents may only select from the embryos which have been created, and genetic characteristics that are not possessed by either parent cannot be added to an embryo. PGD is simply a way for IVF patients and their partners to minimize the risks of genetic disorders.

Gender Selection is used when there is a chance of passing on a gender based genetic abnormality, or for couples who wish to obtain a gender balance in their family planning (controversial though). With AI, IUI and IVF, the sperm sample has been processed to increase the likelihood of obtaining a desired sex.

For parents who would particularly like to have a girl rather than a boy, or a boy rather than a girl, sex selection is an available option to help ensure their child is of the sex they want. There are different methods for selecting the gender of a child. By one of a number of techniques, sperm can be sorted into two groups: those containing the X-chromosome (female) and those containing the Y-chromosome (male). Following the separation of sperm, it may be used for insemination. More definitive technique is after IVF analyze a cell of morula and transfer an embryo of the desired sex. Almost all couples will qualify for at least one sex selection procedure, and PGD can be used to further determine the genetic characteristics of embryos. Although sex by choice is in great demand, it is rarely done because of ethical issues.

Alternatives for Childless Couples There are wives who either have the uterus but not functioning ovaries, or have the ovaries but absent or non functioning uterus. There are husbands who do not have sperms in semen nor spermitids in testes. These alternate approaches for couples are offered in developed countries. These procedures have legal implications differing from country to country.

Gamete Donation Egg donation is a venue for couples in cases of absent or non functioning ovaries or testes. Sperm banks have been maintained for many years; however egg banking is relatively new due to technical problems involved in the freezing of unfertilized eggs. Both egg and sperm donors are evaluated for their physical and psychological suitability as gamete donors. In choosing a donor, couples consult a list with identifying physical characteristics. Both sperm donation and egg donation is preferably anonymous.

Egg donation is done where the wife has functional uterus but the eggs are either not available or are of poor quality, e.g. women over 40 years of age, premature menopause, iatrogenic or genetically defective eggs. Sometimes the ovaries are irreparably damaged during processes such as cancer or radiation chemotherapy. IVF success using donor eggs are high. Donor Egg is used when a woman cannot use her own eggs. IVF using donor eggs has helped thousands of couples be parent when the female partner has ovarian dysfunction or infertility of unknown causes.

Egg donation is done in conjunction with IVF. IVF-ET procedure is exactly the same. The eggs of other woman are taken, which are fertilized with sperms of husband and if successful, fertilized egg is then placed in the wife’s uterus. The child is husband’s raised in wife’s uterus. A birth has been reported where ovarian tissue was preserved and used later for IVF.

Sperm Donation, sperms of another man are taken in a syringe and placed in the vagina of the wife at her fertile period. Wife becomes mother with her own child. Donor sperm has been utilized for many years for couples in which the man does not have sperm, or his sperm does not fertilize eggs. It is also an option for single women who want to have a child without a partner. Donors are chosen from a list of physical and personality characteristics. Fertilization with donor sperm can be accomplished through AI,IUI or IVF.

Surrogacy. When the wife is ovulating and capable of producing eggs but is unable to carry the child to term due to the problems of her uterus, surrogacy is helpful. The baby so achieved is biological child of husband and the wife. The first three stages of ovarian stimulation, eggs retrieval, and fertilization and embryo formation in laboratory are the same. In the fourth stage, the embryo is transferred into the uterus of the surrogate mother instead of into the wife’s uterus. The fetus grows in the uterus of the surrogate mother and after delivery is handed over to the parents whose sperms and ova were used.

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