In Vitro Fertilization & Embryo Transfer (IVF – ET)

IVF is the technique of mixing the women’s eggs (ova) with sperm from her partner in a small dish or test-tube in the laboratory to allow fertilization to occur. Once the ova are fertilized, one or more developing embryos are replaced into the woman’s womb through the cervix. 

IVF treatment is indicated in

Tubal Factor
IVF was developed specifically for women whose fallopian tubes had been injured by prior surgery or infection. For women with significant damage of their tubes, one IVF attempt offers a better chance of a viable pregnancy than surgery at a lower overall cost.

Male Factor
ICSI, where a single sperm, obtained either from semen or from needle aspiration of the testicular sperm ducts is injected inside each mature egg, is the best treatment modality for low or nil sperm count problems.

Endometriosis
While not usually the first line of treatment for this problem, IVF works well for endometriosis. It is the therapy of choice for severe cases or when lesser treatments have failed or for women at or approaching age 40.

Anovulation
The majority of patients with anovulation will conceive using simpler treatments. However, few patients require IVF if repeated ovulation induction fails or there is hyper stimulation of ovaries.

Unexplained Infertility
Approximately 20% of couples will have no identifiable cause of infertility after completing a comprehensive evaluation. IVF is often successful when all conservative treatments have failed, especially since some of these couples actually have some problem in fertilization. Majority of these patients have either poor egg quality or failure of the egg to escape or may have implantation

The Process

The actual procedure involves induction of ovulation followed by egg retrieval. The eggs are then inseminated in lab with semen & the resulting embryos are transferred to uterus after 48-72 hours.

Induction of Ovulation
A woman is born with millions of egg follicles each of which contain an immature egg at its centre. Each month, multiple follicles begin to develop, but only one dominates & matures & finally release into the peritoneal cavity. In order for IVF to be most effective, more than just one mature egg needs to be retrieved. There are special medications that help stimulate the development of multiple follicles together. The most common stimulation protocol used is gonadotropin with GnRH analogues either GnRH antagonists or GnRH agonists. GnRH agonists are started few days prior to the periods & continued afterwards (Long Protocol). Gonodotropins are started from D2 or D3 of periods & on an average nine to ten days stimulation is required. Repeated ultra sonography & estradiol levels are done to see the follicular maturation and when it is judged to be adequate, hCG injection is given for final maturation.

Oocyte retrieval
hCG would lead to ovulation about 36 to 42 hours after injection, but just before that time retrieval procedure is done to recover the egg cells from the ovary. The eggs are retrieved using a transvaginal ultrasound-guided needle piercing the vaginal wall to reach the ovaries. Through this needle follicles can be aspirated, and the follicular fluid is handed to the IVF laboratory to identify ova. The retrieval procedure takes about 15-20 minutes and is usually done under general anesthesia.

Insemination
The embryologist looks for eggs in fluid aspirated from the follicles. The eggs are assessed for maturity and incubated. A semen analysis is performed and the sample is washed with a special solution of nutrients to isolate the more motile sperm. Fertilization is done in the lab. In standard IVF, the sperm is placed into the dish containing the eggs. In ICSI one sperm is drawn up in a needle and then injected into the egg. The actual injection process takes less than 60 seconds.
The sperm and eggs (oocytes) are placed in growth media containing special nutrients that allow them to live outside the body. The egg when fertilized by sperm becomes an embryo that is allowed to grow and divide in the laboratory for two to five days in the special culture media. 

Embryo transfer
Embryo quality is a critical factor affecting the success of IVF. You will be given the detailed information about your egg quality, sperm quality as well as embryo quality. After thorough discussion with you, the best embryos are transferred to the uterus based on grade and cell number. The rest of the embryos can be either discarded or frozen, depending on the embryo quality and your wish.

Embryos are transferred into the uterus through a small tube or catheter. This procedure does not require anesthesia, as it is usually painless. The embryos are placed in a small amount of fluid inside the catheter, which is threaded through the cervix during a speculum examination. The embryos are implanted so that they reach below the top part of the uterus. Abdominal ultrasound is used to confirm the correct placement. Depending on your wish, one to four embryos may be transferred in one treatment cycle. 

Post Transfer
You will have to wait for two weeks for the pregnancy test. During this time you may receive progesterone – a hormone that keeps the uterus lining thickened and suitable for implantation.

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