In Vitro Fertilization (IVF) refers to the fertilization process of oocytes (egg) outside the body. There are a number of steps and variations in the IVF process.

Initially many programs will use oral contraceptives to both take control of a woman’s reproductive cycle and for scheduling IVF cycles (an IVF cycle is one complete IVF process from start to finish.) Two pathways arise where some programs will use a medication, called a long- acting GnRH agonist, with the intention of preventing premature ovulation as the woman goes through the IVF cycle. Another path starts with stimulating the ovary and then adding a GnRH inhibitor to prevent premature ovulation.

Either way, the primary process in IVF is the use of the hormone FSH to promote the development of more than one oocyte. This usually takes 9-12 days of daily injections. Frequently during this stimulation phase of IVF, the developing oocytes are monitored by ultrasound to measure the size of the developing egg units (follicles) and blood estrogen and progesterone levels. When the oocyte is deemed to be mature, the pregnancy hormone (hCG) or the medication called Lupron will be given at a very specific time (trigger).

The oocytes are removed 34-36 hours after the injection and the timing of this is critical. The oocytes are removed vaginally using ultrasound and injecting a thin needle through the vaginal wall and into the ovary. This is done under anesthesia. Once the oocytes ae removed, they are exposed to sperm, either by just mixing the sperm and eggs in a dish or by injecting sperm into the eggs (Intracytoplasmic sperm injection, also known as ICSI).

Once an oocyte fertilizes, it is referred to as an embryo. Embryos are grown in culture media for up to six days. Some embryos will be placed into the uterus (fresh embryo transfer) three to six days after the oocyte retrieval. More commonly, the embryos are frozen and then used in a separate IVF cycle where no stimulation is done. During an embryo transfer, ultrasound is used to help guide the proper placement in the uterus. This procedure is usually well tolerated, and no anesthesia is required.