There are many types of gonadotropins used alone or in combination for ovulation induction. They include hMG (human menopausal gonadotropin Humegon^®), FSH (follicle stimulating hormone Gonal-F^®) and hCG (human chorionic gonadotropin, Profasi^® with the use of these drugs, careful monitoring is required to minimize the side effects, discussed below.

1. Ovarian Hyperstimulation (OHSS)
Occurring in 1 to 5 percent of patients the chance of OHSS is increased in women with polycystic ovarian syndrome and in conception cycles. When severe, it can result in blood clots, kidney damage, ovarian twisting (torsion), and chest and abdominal fluid collections. In severe cases, hospitalization is required for monitoring, but the condition is transient, lasting only a week or so. Occasionally, drawing fluid out of the chest or abdominal final cavity helps. The best prevention is to not give hCG to induce ovulation at the end of an overly vigorous stimulation cycle.

2. Multiple Gestations
Up to 20 percent of pregnancies resulting from gonadotropins are multiple, in contrast to a rate of 1 to 2 percent in the general population. Although most of these pregnancies are twins, a significant percentage are triplets or higher. High-order multiple gestation pregnancy is associated with increased risk of pregnancy loss, premature delivery, infant abnormalities, handicap due to the consequences of very premature delivery, pregnancy induced hypertension, hemorrhage, and other significant maternal complications.

3. Ectopic (Tubal) Pregnancies
While ectopic pregnancies occur 1 to 2 percent of the time, in gonadotropin cycles the rate is slightly increased at 1 to 3 percent. These can be treaded with medicine or surgery. Combined tubal and intrauterine pregnancies (heterotopic pregnancies) occasionally occur with gonadotropins and need to be treated with surgery.

4. Birth Defects
The rate of birth defects after gonadotropin cycles is not higher than in the general population, at 2 to 3 percent. Furthermore, these children are developmentally no different than their peers.

5. Adnexal Torsion (Ovarian Twisting)
Less than 1 percent of the time, the stimulated ovary can twist on itself cutting off its own blood supply. Surgery is required to untwist or even remove the ovary.

6. Gonadotropins and Ovarian Cancer
The risk of ovarian cancer seems in part related to the number of times a woman ovulates. Infertility increases this risk; birth control pill use decreases it. Controversial data exists that associates ovulation stimulation drugs like gonadotropins with the risk of future ovarian cancer. While research is underway to help clarify this issue, the careful use of gonadotropins is still reasonable, especially considering that pregnancy and breast feeding reduce cancer risk.