What is an IVF Cycle?

An IVF cycle is one complete round of in vitro fertilization (IVF) treatment, consisting of several steps and culminating in pregnancy if successful. The cycle of this fertility treatment begins with medications to suppress ovulation while stimulating production of numerous eggs for fertilization. The next step is retrieving the eggs from the ovaries, followed by fertilizing the eggs outside the woman's body in a laboratory setting. Once eggs are fertilized, they are transferred into the woman's uterus with precise timing, with the desired result being a successful pregnancy.

The first step of an IVF cycle is called ovulation induction, and it uses two injectable medications, Lupron and gonadotropin. Lupron suppresses natural ovulation until the right time, and gonadotropin stimulates the production of many eggs for fertilization instead of the usual single egg. During this phase, the woman will make frequent visits to the doctor's office or clinic for ultrasounds to track egg maturation and blood tests to monitor hormone levels. The goal of this step in the IVF cycle is to produce many mature eggs for retrieval and fertilization.

Once enough eggs are mature, the next phase of the IVF cycle is egg retrieval. The eggs are retrieved while the woman is under sedation. A long needle, guided by an ultrasound probe, extracts the fluid containing the eggs from the ovarian follicles where they developed. Once this process is complete, the doctor will combine the woman's eggs with her partner's sperm.

The fertilization portion of the IVF cycle is performed in a laboratory setting. Each egg is placed in a culture dish with thousands of sperm and left overnight for fertilization to occur. The eggs are checked the next morning to confirm fertilization, and again in the afternoon to see if cell division has started. Once cell division starts, they are considered embryos and placed in a solution called media to encourage growth. They can be implanted in the woman's uterus after three to six days of growth or frozen for possible future use.

The implantation procedure is a critical part of the IVF cycle. Two to four embryos are placed into the uterus using a flexible catheter inserted through the cervix. If the cycle is successful, at least one embryo will implant itself into the uterine wall and continue developing, resulting in a successful pregnancy which can be confirmed after two weeks with a pregnancy test. If the attempt fails, the woman can try again at a later date; some women require several cycles to become pregnant.