Follicle Stimulating Hormone (Gonal-F, Bravelle, Menopur, Repronex, Follistim)
Follicle stimulating hormone (FSH) is the hormone responsible for the recruitment and development of ovarian follicles. It is produced by the pituitary after stimulation with gonadotropin releasing hormone (GnRH) which is released by the hypothalamus. When FSH is injected it stimulates the ovaries directly to recruit and develop more follicles which are needed for ART procedures.
These FSH products are known as gonadotropins or menotropins. The first gonadotropin released in the United States was Pergonal. Pergonal was extracted from the urine of postmenopausal women and was considered a “naturally derived” product. Pergonal contained equal amounts of FSH and LH and some considered the LH portion important for follicular and endometrial development.
The direction of the gonadotropin market was towards “purer” products. The first “pure” natural menotropin was Metrodin which contained only trace amounts of LH. The products in use today are pure FSH (Gonal-F, Follistim) being created using genetic recombinant technology in which mammalian cells are “genetically programmed” to produce FSH identical to that found in the human.
There is still debate as to whether additional LH provides for a “better” ovarian hyperstimulation. Some physicians “sweeten” their FSH protocols with LH containing products such as Repronex. Others feel that pure FSH protocols produce higher quality embryos. In our practice, each patient’s drug protocol is individualized based upon many factors including female age, cause(s) of infertility, stimulation history, and other factors.
Drug protocols indicate which drug(s) is administered and the frequency and timing of injections. Patients undergoing ovulation induction with FSH must visit our office frequently during their stimulation cycle for ultrasound and estradiol monitoring. These measurements are used to adjust medication dosages to provide an optimal stimulation and avoid drug side effects.
FSH should only be administered by a reproductive endocrinologist/infertility specialist thoroughly familiar with its use. One side effect of FSH stimulation for IUI is an increased chance of high order multiple births. These patients must be carefully monitored by a specialist to limit the chances of multiples. Many of the cases of quads, and above, are due to IUI cycles managed by non specialists. High order births are less common when IVF is employed because the specialist controls the number of embryos transferred to the uterus.