Fertility Drugs for the Stimulation of Egg Development in IVF
Fertility drugs for IVF – in vitro fertilization contain the same hormones that the body normally uses to stimulate eggs to develop in the ovary. These hormones are called gonadotropins. There are two gonadotropins in human beings that stimulate egg development. These two hormones are known as follicle stimulating hormone (FSH) and luteinizing hormone (LH). The amounts of these fertility drugs that are administered in IVF cycles are typically higher than the levels a woman would produce naturally. This hopefully increases the number of eggs that mature and thus multiple eggs will be available for removal and fertilization.
There are several companies that manufacture these fertility drugs and several different brand names are available. The newest types of gonadotropins are made from recombinant DNA technology and include Gonal F and Follistim. Gonal F and Follistim contain the most highly purified preparation of FSH possible. The older versions of gonadotropins are isolated from the urine of post-menopausal women and include those which contain FSH and LH such as Pergonal, Repronex, Humegon, and Menopur, and those contain mostly FSH such as Fertinex, Metrodin and Bravelle. All of these medications are expensive.
A third type of gonadotropin is called human chorionic gonadotropin (hCG). HCG is normally produced by the developing placenta during pregnancy. However, hCG is very similar in structure to luteinizing hormone (LH). When administered as an injection to a non-pregnant woman, hCG acts the same way that luteinizing hormone (LH) does. The advantage is that hCG lasts a lot longer in the body than LH does and therefore has a more reliable, consistent effect. Because of these features, hCG is much more potent than LH. Some brand names of human chorionic gonadotropin (hCG) include Profasi, Pregnyl and Novarel. It may also be referred to as chorionic gonadotropins for injection.
For IVF stimulation, we like to use a combination of two fertility drugs. A recombinant FSH product such as Follistim and a low dose of hCG. This is known as the low dose hCG protocol.
In a normal reproductive cycle, the early development of the follicles are stimulated predominantly by FSH. Their later development is controlled by LH. Therefore, when we perform an IVF stimulation, we like to mimic that same pattern. The stimulation begins with FSH alone using Follisitm. Once the follicles have reached a certain size as measured by the ultrasound, the Follistim dose is reduced or stopped completely and low dose hCG is administered.
IVF programs that use older stimulation protocols may continue to give their patients a high dose of FSH during the entire stimulation. This can work. However, the FSH is much more expensive than hCG and will likely raise the cost of the IVF cycle by a few thousand dollars.
In addition, there is some evidence to suggest that the risk of over-stimulation of the ovaries is reduced with the low dose hCG protocol.
All of these fertility drugs are self administered by the patient each evening. All are given as a subcutaneous injection. Gonal F and Follistim come in various types of preparations. The low dose hCG comes premixed and is stored in the refrigerator.
Learn more about mixing and giving fertility drugs
During the time that the patient is being stimulated with fertility drugs, she will come to the office early in the morning at periodic intervals to have a blood test and ultrasound to monitor her response. Depending on her response, she may need 3-5 visits to be monitored. Usually the first day of monitoring is after 4-5 days of medication. Most women will end up taking 9-11 days of medication before her eggs appear ready to be removed (egg retrieval). Unfortunately, we can’t predict ahead of time how long any individual patient will need.
Each time a woman comes in for monitoring in the morning, she will be given instructions that evening as to what dose of medication to take and when to come for the next monitoring visit. Patients in our practice will follow all their monitoring, test results and instructions through our patient portal.
Learn about the IVF hCG Trigger injection to prepare for egg retrieval.