Embryo Project Encyclopedia Articles

Assisted reproductive technologies (ART) are a collection of different techniques designed to help those who are infertile achieve a successful pregnancy. The most popular technology currently in use is in vitro fertilization (IVF), but others include gamete intrafallopian transfer (GIFT), zygote intrafallopian transfer (ZIFT), intrauterine insemination (IUI), and intracytoplasmic sperm injection (ICSI). Although not encompassed under the umbrella term of ART, there are also various hormonal medications that can induce ovulation such as clomiphene citrate that can either be used alone to help women conceive, or used in conjunction with the above techniques. Infertility is a problem that has affected people throughout history, but it was only in the last half of the twentieth century that medical research developed technologies to help those who are infertile become pregnant.

Zygote intrafallopian transfer (ZIFT) is an assisted reproductive technology (ART) first used in 1986 to help those who are infertile conceive a child. ZIFT is a hybrid technique derived from a combination of in vitro fertilization (IVF) and gamete intrafallopian transfer (GIFT) procedures. Despite a relatively high success rate close to that of IVF, it is not as common as its parent procedures due to its costs and more invasive techniques. Some patients prefer ZIFT, however, considering it more natural because the fertilized oocyte, the zygote, is placed in the woman's body for implantation much sooner than with IVF.

Intracytoplasmic Sperm Injection (ICSI) is an assisted reproductive technique (ART) initially developed by Dr. Gianpiero D. Palermo in 1993 to treat male infertility. It is most commonly used in conjunction with in vitro fertilization (IVF) or a less commonly used technique called zygote intrafallopian transfer (ZIFT). In natural fertilization, the sperm must penetrate the surface of the female egg, or oocyte. When the male has a fertility problem such as low sperm count, malformed sperm shape, or sperm immobility, there is a significant decrease in the chance a healthy sperm will penetrate the outer surface of the oocyte. Other fertility problems ICSI can be used to overcome include the sperm having trouble attaching to the egg or the male having a blockage in his reproductive tract preventing normal ejaculation. In this procedure, the physician first obtains the sperm and oocytes from the male and female and then manually injects the sperm through a needle into the oocyte to fertilize it in an injection plate. The physician then places the fertilized egg into the female s uterus for implantation, following IVF procedures.

Intrauterine insemination (IUI), also known as artificial insemination, is one of the earliest and simplest assisted reproductive technologies (ART). With this technique, sperm from either a partner or donor (such as from a sperm bank) is inserted with a syringe into the woman's vagina during ovulation to increase the probability that fertilization will occur and lead to pregnancy. This procedure is most effective for couples with male fertility problems, such as impotence, though it is also used to treat idiopathic (of unknown cause) infertility, vaginismus (wherein the female involuntarily constricts her vagina), and hostile female cervical mucus that rejects the male's sperm. In the 1940s and 1950s cryopreservation facilitated the preservation of sperm through freezing methods for later use, such as in IUI.

In vitro fertilization (IVF) is an assisted reproductive technology (ART) initially introduced by Patrick Steptoe and Robert Edwards in the 1970s to treat female infertility caused by damaged or blocked fallopian tubes. This major breakthrough in embryo research has provided large numbers of women the possibility of becoming pregnant, and subsequent advances have dramatically increased their chances. IVF is a laboratory procedure in which sperm and egg are fertilized outside the body; the term "in vitro" is Latin for "in glass."