“In vitro,” which means “in glass,” is a procedure in which a woman’s eggs are fertilized with a man’s sperm outside the body. There are many reasons why a couple might consider IVF (in vitro fertilization): blocked fallopian tubes, lack of response to infertility medication, low sperm count or sperm that are slow, or unexplained infertility. One cycle of IVF can take anywhere from 6 weeks to 2 months and, according to the Center for Human Reproduction, is successful about 50 percent of the time.
To start the IVF cycle, the patient is placed on a course of drug therapy that suppresses the production of her own hormones, a regiment that usually lasts 21 days. Afterward, she begins another round of hormones to stimulate the production of eggs. Whereas a woman normally produces one egg during the course of her menstrual cycle, the intent of the drugs is to stimulate the production of 7 to 15 eggs. The patient’s reproductive endocrinologist will closely monitor the status of the developing eggs using ultrasound technology and, just before they are fully mature, she will receive an injection of a hormone called HCG (human chronic gonadotropin).
Thirty-four to 36 hours after the injection, egg retrieval will begin. This is done in the clinic under IV sedation and as an outpatient procedure. Egg retrieval, which is done using a long needle, is relatively quick and painless; however, some women might experience minor discomfort or slight bleeding after. During the same visit, the man will be asked to provide a semen sample in order to collect his sperm. To increase sperm count, the man is requested to not masturbate two days prior to the collection date.
After the eggs and sperm have been collected, they are immediately taken to the lab. There, the eggs are put in a petri dish full of culture medium. The dish is then placed in an incubator with a temperature the same as the human body, and the sperm is introduced. The eggs are monitored daily and, if fertilization has occurred, they can be transferred to the patient in 3 to 5 days.
In a procedure that is not any more uncomfortable than a Pap smear, one to three embryos are transferred to the uterus. The embryos are placed in a catheter of fluid, which is inserted through the vagina and cervix into the uterus. Once the transfer is complete, the patient is advised to rest in bed for the remainder of the day and may resume light activity the next.
Following the transfer, the patient will be placed on a regiment of progesterone, a hormone that supports pregnancy. Fourteen days following the procedure, a sample of blood will be tested to measure the levels of the pregnancy hormone HCG. If tests reveal she is pregnant, she will undergo an ultrasound 2 weeks later. Once it is determine that the patient is, indeed, pregnant and the embryos are viable, she will be released to the care of her obstetrician.
How Does IVF Work?