In Vitro Fertilization (IVF) literally means "fertilization outside of the body". IVF involves combining eggs and sperm in a Petri dish, incubating the resultant embryos, and when mature, transferring the embryos to the mother's uterus.
The first successful IVF cycle was performed in 1978 by Drs. Steptoe and Edwards in London England and resulted in the birth of Louise Brown. IVF was considered an "experimental procedure" for many years; however, it is now an accepted therapy for infertility and is used as a "first line" treatment in many patient types, such as those with tubal disease. The first successful IVF birth in the US was in December of 1981 with the team from the Jones Institute in Norfolk, Virginia This was followed five months later with the birth from the second successful IVF team in America at the University of Southern California under the direction of Dr. Richard Marrs, a close personal friend of Dr. Webster.
IVF involves several stages, which are performed by the embryologist and physician. The ovaries must be stimulated using drugs to produce numerous eggs for use in the IVF cycle. Most eggs are not genetically capable of producing babies, so more eggs increase the odds of having good eggs.
FSH/LH is given by injection in an IVF cycle, which bypasses the normal feedback/regulation mechanism allowing the development of multiple eggs.
IVF patients are given Lupron, Antagon or Cetrotide to stop the production of internal reproductive hormones allowing the physician to control the stimulation cycle by preventing the LH surge. In a normal cycle, once the follicles mature, the pituitary releases a surge of luteinizing hormone, which initiates ovulation. In an IVF cycle, ovulation must not occur prior to egg retrieval or the cycle will be lost. Ovulation cannot occur while Lupron or Antagon are given unless an injection of hCGor LH is given.
Patients undergoing an IVF cycle must come to our clinic at regular intervals for ultrasound monitoring and estradiol hormone measurements. The physician uses ultrasound to visualize the follicles, the ovaries, and the lining of the uterus (endometrium). Medication dosages are adjusted to insure the development of sufficient eggs while limiting the chances for adverse side effects. Estrogen levels increase as the follicles mature and highly elevated levels are associated with ovarian hyperstimulation syndrome (OHSS). OHSS can be serious resulting in enlarged ovaries and systemic side effects such as stroke. The physician carefully individualizes the medication dose for each patient thus limiting the chances for side effects.
Once the follicles mature, an injection of hCG is given and egg retrieval is scheduled. Egg retrieval is accomplished by "ultrasound guided transvaginal aspiration". A small needle is passed through the top of the vagina into the follicle and the eggs are retrieved when the follicle fluid is aspirated and the follicle is drained. This procedure is done using light anesthesia. The eggs are passed to the embryologist who separates them from the follicular fluid and places them in Petri dishes containing specially prepared solutions. Sperm is obtained from the male partner prior to the egg retrieval and washed and prepared. This sperm is then placed in the Petri dishes with the eggs. Successful fertilization requires that one sperm attach to and penetrate an egg. Oftentimes, more embryos are created than can be safety transferred to the mother. When this occurs some of the embryos are cryopreserved for use in the future.
Gametes (egg and sperm) contain half of the mother's and father's genetic material unlike other cells that contain a full complement. When the sperm and eggs combine the resultant embryo has a full set of chromosomes, half from each parent.
In some cases, there are not enough "quality" sperm available to penetrate the egg and cause fertilization. Intracytoplasmic sperm injection (ICSI) is a procedure where a single sperm is inserted directly into the egg. ICSI can be successful when as few as one sperm is available. ICSI was a major advance in treating male infertilitymaking it possible for men with no ejaculate to produce a genetically related child. Our Louisiana male infertilitytreatment program often recommends ICSI in cases of male factor infertility.
The fertilized eggs are transferred to an incubator and allowed to culture until they are ready for transfer. This could be from 3-6 days and is case specific. Once mature, the embryo transfer procedure is scheduled. Embryo transfer is a painless procedure requiring less than ten minutes where the embryos are placed into the mother's uterus using a small catheter. Once inside the uterus, the embryo implants into the endometrium (lining of the uterus) and continues to divide and develop into a fetus.
IVF is a first line treatment for some conditions including moderate to severe damage to the fallopian tubes and male factor infertility. When the tubes are damaged the eggs cannot travel through them to the site of fertilization. IVF avoids the tubes because the eggs are retrieved directly from the follicles and combined with the sperm. IVF is also used in cases where traditional therapy has been unsuccessful.