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Assisted Reproductive Technologies (ART) is a term used to describe advanced fertility therapies. It most commonly refers to in vitro fertilization-embryo transfer (IVF-ET or IVF) but also includes other therapies. These procedures all involve the removal of a woman’s eggs from her ovaries, processing these eggs with sperm, and returning the eggs to the woman, sometimes already fertilized, in order to achieve a pregnancy. The differences in the procedures involve where the eggs become fertilized, and how far along the fertilization process has progressed before they are returned to the uterus.
Although ART have helped many people overcome their infertility, they are not the answer for every infertile couple. Most of the time we use ART only when less complex and less expensive methods of treatment don’t succeed. However, in certain circumstances (such as advanced age or severe male factor) we may recommend ART as first-line therapy.
We will carefully and thoroughly review your medical history with you to determine the procedure most appropriate for achieving your goal of a healthy pregnancy. Your medical history will be considered and medical testing will be performed prior to determining the appropriate treatment options.
ART Options
In addition to IVF and IUI, Fertility Physicians of Northern California offers other advanced services available to optimize your chances for a successful pregnancy.
Additional services such as sperm donation and surrogacy are also provided for selected patients.
Gamete Intrafallopian Transfer (GIFT), Zygote Intrafallopian Transfer (ZIFT), Tubal Embryo Transfer (TET)
IVF, GIFT, ZIFT, and TET are very similar procedures although there are a few significant differences. During IVF, ZIFT, and TET, the oocytes and sperm are combined in a culture dish in the laboratory. Fertilization and very early embryo development occur outside the body, rather than in the fallopian tube. Once early embryo development is recognized, the embryos are transferred either into the uterus (IVF) or the fallopian tube (ZIFT, TET). Since most programs have seen no significant difference in success rates, they usually perform IVF because it is less expensive and doesn't require laparoscopy and general anesthesia. In addition, IVF is the only procedure available for women with damaged fallopian tubes.
GIFT differs from the other procedures in that sperm and oocytes are transferred into the fallopian tubes immediately after oocyte retrieval. Fertilization thus occurs in the body, rather than in the laboratory. GIFT originally was thought to represent a breakthrough in infertility therapy. However, many investigators have concluded that GIFT does not increase the likelihood of conception compared to other ART procedures. In addition, GIFT does not allow for confirmation of successful fertilization if the procedure does not produce a pregnancy. Your physician will discuss each of these procedures with you so that the most appropriate procedure for your individual situation will be used.
Intracytoplasmic Sperm Injection (ICSI)
The ICSI technique has been developed over the past 10 years to treat cases of severe male factor infertility. Candidates for ICSI may include patients with severe reductions in sperm number or motility, regardless of cause, and patients with a history of failure of fertilization in conventional IVF. The ICSI technique may also be used to achieve fertilization using surgically extracted sperm from patients with anatomic or surgical conditions (such as vasectomy) that prevent sperm from entering the ejaculate. In all these cases, donor sperm or ICSI may provide the only options for conception.
The ICSI technique attempts to achieve fertilization by the direct injection of a single sperm into the cytoplasm (interior) of the egg. Mature eggs are freed of surrounding cells by a combination of enzyme treatment and microdissection. Using special micromanipulation equipment, the eggs are individually injected with a single sperm. Injected eggs are returned to the laboratory incubator and are treated thereafter as in conventional IVF.
An alternative to ICSI is the use of donor sperm. Donor sperm normalizes the success of conventional IVF in couples with severe male factor infertility. In cases where male factor is the only diagnosis, pregnancies with donor sperm can be achieved through timed insemination, a treatment far less expensive and complicated than IVF.
Testicular Sperm Extraction (TESE), Microsurgical Epididymal Sperm Aspiration (MESA)
TESE and MESA are used to extract sperm directly from the male partner. The TESE procedure involves aspirating the sperm directly from the testes or obtaining sperm from a testicular biopsy. TESE usually recovers enough sperm for one IVF/ICSI case. The MESA procedure involves aspirating sperm from the epididymus, the tubules next to the testicles that collect the sperm. MESA allows for the collection of millions of motile sperm, although this sperm can not yet penetrate an egg and must be injected into eggs using ICSI. Because MESA typically collects millions of sperm, some can usually be frozen for multiple IVF/ICSI procedures.
Assisted Hatching
Normally, embryos are transferred to the uterus three days after retrieval. Usually the embryos consist of six to eight cells at this stage. After transfer, the embryo must continue to develop to the blastocyst stage (about 100 cells) before implantation can occur. This development takes several days. Immediately before implantation, the blastocyst must "'hatch" from the zona coating which originally enveloped the oocyte. To assist the hatching process, we micromanipulate the embryos immediately before embryo transfer. This involves creating an opening in the zona coating with a dilute acid solution or laser. Trained personnel using specialized micromanipulation tools must perform this under the microscope. There is a small risk of damage to the embryos from the procedure.
Pre-Implantation Genetic Diagnosis (PGD)
New laboratory techniques and DNA technology make genetic diagnosis possible before implanting an embryo. Once an embryo has developed to 8 cells, micromanipulation is used to remove a single cell for genetic analysis. The DNA material from this cell is then tested for a variety of inherited and chromosomal factors. For patients with certain inherited diseases, PGD allows us to select unaffected embryos for transfer to the uterus.
Sperm Chromatin Structure Assay (SCSA)
A male may have a good sperm count, good sperm motility, and normal sperm shape, but still exhibit a high degree of fragmentation (small breaks in the sperm chromosomes) which may be related to a couple’s fertility problems. SCSA can distinguish normal sperm from those with fragmentation in their DNA. Using special stains and highly technical instrumentation (flow cytometer), a laser beam is used to quantitate the percentage of sperm with intact vs. fragmented DNA.
Cryopreservation Of Embryos
Embryos that meet developmental criteria for appearance and rate of growth can be frozen at any of several stages in their development. The freezing process is computer controlled and employs special solutions to protect the fertilized eggs from damage. Frozen embryos are stored at -196°C or approximately- 400°F (below zero). Cryopreservation is often used when there are more embryos than needed for a single IVF transfer. Embryo cryopreservation can provide a second or even third opportunity for pregnancy without undergoing another ovarian stimulation and retrieval.
As with cryopreserved semen, many embryos do not survive cryopreservation and thawing. Those that do survive may implant and produce ongoing pregnancies at a somewhat lower rate than fresh embryos. There is no known increase in the rate of spontaneous miscarriages or in the rate of birth defects from pregnancies which have resulted from the implantation of previously frozen and thawed embryos.
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