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How Does IVF Work?

 In vitro fertilization (IVF) is the process of fertilizing a human egg outside of the body, then placing the early embryo (or blastocyst) in a woman's uterus. IVF is most commonly used when a couple cannot conceive on their own.

"In vitro fertilization is also used to prevent genetic diseases that may be of concern to the parents," says Megan Link, MD, a reproductive expert with University of Utah Health. The process has become relatively routine, and complications are extremely rare. Although not every IVF procedure yields a pregnancy, it has become a viable option for those who cannot become pregnant on their own.

The IVF Process

There are five main steps to in vitro fertilization:

  1. Stimulation of the Ovaries - Three days after a menstrual cycle begins, a hormone shot is self-administered just under the skin around the stomach. This is done daily for nine to ten days, on average. This stimulates the ovaries to bring multiple eggs to maturity.
  2. Retrieval of the Eggs - Once it's determined that eggs are ready for extraction, one last "trigger" shot is self-administered to prepare the eggs for retrieval. About 36 hours later, all viable eggs are removed through a needle during an office visit. Multiple eggs are extracted in the hope of increasing the chances of successful fertilization.
  3. Retrieval of the Sperm - If the woman's partner has a low sperm count or has had a vasectomy, sperm can be extracted directly from the testicles. Otherwise, sperm usually comes fresh from the partner. Previously frozen sperm, such as that from a donor, can also be used.
  4. Fertilization of the Eggs - The sperm and eggs are united in a laboratory dish. As the cells begin to divide and multiply, they are watched very closely and can be tested for genetic diseases. The healthiest fertilized egg, called a blastocyst, then has the potential to implant when transferred. If multiple blastocysts mature and their cells keep dividing, they can be frozen and preserved for a later transfer.
  5. Transfer of the Embryo - Approximately five days after fertilization, the mature blastocyst is passed through the cervix and into the uterus through a catheter. This short process is similar to a pap smear where a speculum is used to open the vagina. After two weeks, an office visit is made to determine if the transfer was successful in achieving pregnancy.

Is It Painful?

Most women report that their amount of worry was more than the pain itself. The needles used for the self-administered shots are very thin, minimizing pain. When the ovaries are stimulated, they become larger than normal, which can create some bloating and discomfort.

The egg retrieval is done under moderate sedation of the patient. There may be some soreness afterward, but there is little to no pain during the procedure. During embryo transfer there can be some mild discomfort.

When Should You Consider IVF?

It all depends on your age and situation. As you get older, time is of the essence. The sooner healthy eggs can be retrieved, the better your chances of a successful pregnancy.

If you are under 35 years of age, you should consider IVF after one year of trying to conceive. If you are between 35 and 40, IVF is recommended after six months of trying. And it's three months if you are over the age of 40. Consulting a reproductive endocrinologist (RE) can help you determine if IVF is a viable option for your health and situation.