In vitro fertilization is one of the most popular ways of assisting women who have difficulty getting pregnant. The process involves encouraging ovum development in the patient through hormonal therapy, extracting the ova for external fertilization, and implanting the fertilized ovum in the patient's uterus. The length of the in vitro process is variable, depending on the patient's ability to conceive. After roughly 40 days to two months of preparation, a single cycle of in vitro fertilization takes about three to four weeks. Some patients might need to undergo several cycles before successfully getting pregnant, making the in vitro process last several months.
The first step of the in vitro process involves allowing the patient to undergo one uninterrupted menstrual cycle in order to help the ovaries and uterus prepare for the procedure. This can take anywhere from 20 to 36 days, given normal cycles. During this time, the patient can undergo medical and psychological testing to determine whether or not in vitro fertilization is a viable option.
After the initial cycle, the patient will then have to undergo hormonal therapy throughout another menstrual cycle. This stage of the in vitro process involves medications that boost egg cell production in women. Depending on both the medication used and the patient's own body chemistry, this can result in one to seven or more healthy egg cells. This will take another 20 to 36 days, assuming the patient has fairly regular cycles.
Doctors will then test the patient's blood to determine whether or not the egg cells are ready. If the results are favorable, the eggs can be extracted from the patient's ovaries. The entire procedure, from preparation to finish, can take a few hours. The freshly-extracted eggs will then be tested for viability, with the best specimen to be used for the next stage of the in vitro process—fertilization. Patients can sometimes choose to have other viable specimens frozen for later use.
Fertilizing the extracted egg is done in a laboratory, and can take a few minutes to about an hour. If the artificial insemination is successful, the fertilized egg will be kept in safe storage for about three to four weeks. This ensures the egg will develop into a viable zygote healthy enough to survive implantation during the next part of the in vitro process. About two weeks after implantation, the patient will be examined to determine if the pregnancy was successful. If at any point the pregnancy fails, the patient will have to undergo the entire in vitro process once again.
