In Vitro Fertilization overview

In vitro fertizliation

Assisted reproductive technology (ART) refers to any infertility procedures that involve the handling of eggs and sperm outside of the body. The most common ART treatment is called in vitro fertilization (IVF). Worldwide, over 3 million babies have been born through IVF.

IVF Success Rate

Overall, the pregnancy rate per IVF cycle is 35%. In the United States, approximately 120,000 IVF procedures are performed each year.

45% success rate for women under age 35
37% success rate for women aged 35 to 37
28% success rate for women aged 38 to 40
17% success rate for women aged over 40

IVF Eligibility

IVF treatment is usually recommended only after other less invasive treatments, such as IUI, have failed. An expedited IVF treatment plan may be an option for women over 35, because of decreasing success rates in older women. Earlier treatment may also be an option in patients with diagnosed reproductive problems, such as amenorrhea, tubal disease, or endometriosis.

IVF treatment has a high rate of success in treating infertile couples. IVF is used to treat couples that have these fertility problems:

• Fallopian tube disease - blocked or absent tubes
• Irregular ovulation – oligomenorrhea, amenorrhea, hypogonadotropic hypogonadism, polycystic ovarian syndrome (PCOS)
• Endometriosis
• Diminished ovarian reserve
• Uterine abnormalities, including prior hysterectomy, severe fibroid disease, or Asherman’s syndrome
• Male infertility, including low sperm mobility or low sperm counts
• Unexplained infertility

IVF Procedure

An IVF procedure involves the retrieval of oocytes from the ovaries and fertilizing it with sperm in an outside laboratory environment. The fertilized egg, or embryo, is then transferred into the uterus. An IVF treatment cycle will last several weeks.

IVF steps include:

Ovarian Stimulation – medications are given to increase the number of oocytes that will be available for retrieval. Regular ultrasounds and E2 (estrogen) levels will be taken to monitor the activity of follicular recruitment. Mature follicles are about 17-20 mm in diameter and can be monitored by ultrasound imaging. An hCG shot containing LH will be given to induce a timed ovulation, followed by a retrieval procedure called follicular aspiration (step 2).

Medication options will depend on the woman’s cause of infertility and case history. Medication protocols will vary individually. Medication options for ovarian stimulation include:

• hMG (injectable gonadotropins) containing FSH and/or LH - women begin hMG injections on day 2 of their menstrual cycle.
• Repronex/Menopur – contains FSH and LH
• Bravelle/Gonal-F, Follistim – contains FSH only
• Clomid and hMG – combination of medications can increase the number of recruited follicles. Clomid is given for 5-7 days, followed by hMG shots for 2-7 days.
• GnRH agonists (Lupron)
• GnRHa antagonists (Plenaxis, Cetrotide, Antagon)

Ovarian hyperstimulation syndrome is a condition that enlarges the ovaries in response to the medications. OHSS occurs in up to 6% of women. An IVF cycle may be cancelled if the ovaries are overstimulated or if estrogen levels are too high.

Egg Retrieval (follicular aspiration) – follicular aspiration is a procedure that retrieves the oocytes from the ovaries, approximately 34 to 36 hours after the hCG injection. The procedure takes under 30 minutes and is performed while the woman is sedated. An ultrasound probe with an attached needle is inserted thru the vagina. The needle will then draw out the fluid, which contains the eggs.

Oocyte classification – once the eggs are drawn out of the ovaries, they will be inspected under a microscope and classified by quality.

Fertilization – a semen sample will be taken around the same time of egg retrieval. Men should not ejaculate for about 3 to 5 days prior to the semen sample. Men with very low sperm counts should not ejaculate for approximately 5 days. Some men with severe infertility may require an intracytoplasmic sperm injection (ICSI) procedure, which requires only one single sperm per oocyte. Semen samples are then prepared and added to the eggs.

A fertilized egg begins as a single cell and undergoes a series of cleavage divisions, progressing through 2-cell, 4-cell, 8-cell and 16 cell stages. Fertilized eggs are incubated for several days until the embryo reaches the cleavage or blastocyst stage.

Embryo Transfer – the transfer of the embryo is performed at day 3 (cleavage stage) or day 5 (blastocyst stage). The embryo is transferred into the uterus by a catheter that is inserted through the cervix. The woman should lie flat on her back for at least 30-60 minutes.

The number of embryos transferred depends on the woman’s age, health, and embryo quality. For women under 35 years old, no more than 2 embryos should be transferred. Unused embryos may be frozen and preserved for future IVF cycles.

Luteal Phase Management – progesterone medication increase the chances of the embryo implanting to the uterus. Most women will start taking progesterone medication on the day of embryonic transfer for up to 12 weeks, if pregnancy has occurred.