What is In Vitro Fertilization (IVF)?
In Vitro Fertilization (IVF) provides an alternative method of achieving a pregnancy for couples who have tried and have been unsuccessful with other fertility treatments. In many cases, it is the therapy of first choice. In a normal conception cycle, an egg is released from the ovary and unites with a sperm cell that has traveled through the uterus and fallopian tubes after being deposited in the vagina during intercourse. When the sperm penetrates the egg, fertilization occurs. The fertilized egg develops further as it moves through the tube into the uterus. Implantation does not occur until several days after fertilization.
The IVF procedure allows the union of the egg and the sperm and early growth of the embryo to occur in the laboratory. For a pregnancy to result through IVF, four steps must be successfully completed. Pregnancy cannot occur if even one step of the procedures fails. These four steps are as follows:
- Retrieval of the mature egg. Fertility drugs (hMG,
Follistim, Gonal-F, or Humagon) are used to ripen more than one
egg. This process is called controlled ovarian hyperstimulation.
Eggs are recovered by transvaginal ultrasound directed
aspiration of the follicles. Intravenous sedation is used.
Because timing of the egg collection is critical, ultrasound
monitoring and hormone tests are done before egg retrieval.
- Sperm collection, fertilization, and embryo development.
A semen specimen is obtained and prepared at the appropriate
time in relationship to the egg recovery. Meanwhile, the eggs
are placed in culture medium to incubate and mature until timing
is optimal for fertilization by the sperm. The resulting zygote
is called a pre-embryo. In nature as well as in the laboratory,
fertilization may not occur, nor does development always
continue once the egg is penetrated by sperm.
- Transfer of the developing embryo(s) into the uterus.
On the third or fifth day after egg recovery, the embryo(s) are
transferred into a small tube through the cervix into the
uterus. This process is technically much simpler than the egg
retrieval in that it does not require anesthesia and is like a
regular pelvic exam.
- Implantation and growth of the embryo(s). After fertilization and transfer, further development and implantation of the embryo(s) in the uterine lining is governed by hormones, receptors on the uterine lining, and other unknown factors. Blood tests will be taken to detect pregnancy. Additional hormones are given to support the early pregnancy.
Results of IVF-ET Therapy
Couples need to be aware that the federal government requires all IVF programs to provide cycle-specific data to the CDC (Centers for Disease Control). The CDC periodically audits all programs to verify information they have been given regarding cycle success. Information on our program, as well as other reporting programs, can be obtained directly from the CDC, Resolve, and the American Society of Reproductive Medicine.
Human reproduction is a surprisingly inefficient process. There is no IVF-ET program that can provide a guarantee of success. Success is influenced by the quality and number of embryos transferred, and the patient's medical condition. Age is the most important determinate of success. In 1997 and 1998, this program achieved success in over 50% of initiated cycles in women under 40. Because of the higher pregnancy rate and the high multiple pregnancy rate, we are recommending that only two or three embryos be transferred in the future. 1998 showed the wisdom in this recommendation. The average number of embryos transferred dropped to approximately 2.7 while the pregnancy rate did not fall compared to 1997. The risk of multiple pregnancy dropped dramatically. The number of embryos transferred will be determined by your age and quality of the embryos.
Information for all prospective IVF patients
- Our policy requires that all female partners entering the
program be tested for antibodies against Rubella. If antibodies
are not detected, you should consider Rubella vaccination.
Receiving the vaccine will require a three month delay before
entering an IVF cycle. At the conclusion of the three month
waiting period, a repeat titer should be drawn to verify that
antibodies are present. Obviously, not everyone can wait three
months before proceeding with a cycle. Exceptions will be made
on an individual basis.
- Drugs, alcohol, and cigarette smoking should be eliminated
during the IVF cycle. Pregnancy rates in smokers is almost
There have been recent suggestions that eliminating caffeine may
increase pregnancy rates.
- Sitting in hot tubs and saunas is not recommended during the
- Do not begin any new exercise, sport, or intense athletic
training during the IVF cycle.
- All women attempting conception should be taking a specific prenatal vitamin. No other supplements should be taken unless specifically prescribed.