Indications
IVF may be used to overcome female infertility in the woman due to problems of the fallopian tube, making fertilisation in vivo difficult. It may also assist in male infertility, where there is a defect in sperm quality, and in such cases intracytoplasmic sperm injection (ICSI) may be used, where a sperm cell is injected directly into the egg cell. This is used when sperm have difficulty penetrating the egg, and in these cases the partner's or a donor's sperm may be used. ICSI is also used when sperm numbers are very low. ICSI results in success rates equal to those of IVF.
For IVF to be successful it typically requires healthy ova, sperm that can fertilize, and a uterus that can maintain a pregnancy. Due to the costs of the procedure, IVF is generally attempted only after less expensive options have failed.
IVF can also be used with egg donation or surrogacy where the woman providing the egg isn't the same who will carry the pregnancy to term. This means that IVF can be used for females who have already gone through menopause. The donated oocyte can be fertilised in a crucible. If the fertilisation is successful, the embryo will be transferred into the uterus, within which it may implant.
IVF can also be combined with preimplantation genetic diagnosis (PGD) to rule out presence of genetic disorders. A similar but more general test has been developed called Preimplantation Genetic Haplotyping
Read more about this topic: In Vitro Fertilisation
Famous quotes containing the word indications:
“It is difficult to write a paradiso when all the superficial indications are that you ought to write an apocalypse. It is obviously much easier to find inhabitants for an inferno or even a purgatorio.”
—Ezra Pound (1885–1972)
“You must labour to acquire that great and uncommon talent of hating with good breeding, and loving with prudence; to make no quarrel irreconcilable by silly and unnecessary indications of anger; and no friendship dangerous, in care it breaks, by a wanton, indiscreet, and unreserved confidence.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
“The indications are that swearing preceded the development of cursing. That is, expletives, maledictions, exclamations, and imprecations of the immediately explosive or vituperative kind preceded the speechmaking and later rituals involved in the deliberate apportioning of the fate of an enemy. Swearing of the former variety is from the lips only, but the latter is from the heart. Damn it! is not that same as Damn you!”
—Ashley Montagu (b. 1905)