Gonadotropins (menotropins) are a powerful group of medications in which the active component (in terms of ovulation induction or enhancement) is follicle stimulating hormone (FSH). The unit of measurement for FSH is the International Unit (IU), which is based on an international reference preparation (IRP). One ampule of lyophilized (freeze dried) FSH generally has 75 IU of FSH (doses of FSH may vary so you should carefully read the label).
Some menotropins, such as Pergonal and Repronex, also contain LH (usually the amount [immunoreactivity] of LH equals the amount of FSH). LH stimulates the production of estrogenís precursor hormones (androstenedione and testosterone) in the ovary. Many women normally secrete adequate LH even during controlled ovarian hyperstimulation, making the addition of LH in these medications unnecessary. During IVF cycles when there is a push for maximal egg development (or with women who have a very high response to FSH), the anticipated estrogen production is quite large so many infertility specialists prefer to supplement with at least some LH. Also, there are some (uncommon) women (with hypogonadotropic hypogonadism) who do not produce LH in adequate amounts and these women benefit from the additional LH.
Menotropins are contraindicated in women with no ovarian reserve (menopause). A woman with early ovarian failure will occasionally have spontaneous recovery of ovulation (for unknown reasons) but attempts at ovulation induction or enhancement in these women are usually unrewarding. Ovulation induction can be considered if the FSH concentration is less than the LH concentration and/or the estradiol concentration is greater than 40 pg/mL (the amount required for a progesterone withdrawal flow).
A basic infertility evaluation should be completed prior to the use of menotropins. There should always be documentation of tubal patency and availability of sperm prior to initiating treatment with menotropins. I often recommend a laparoscopy to assess and optimize the pelvis prior to menotropin therapy. An exception is when the only finding on evaluation is a clear-cut ovulation disorder. The appropriateness of laparoscopy should be individually discussed with each couple considering menotropins.
Menotropins are injectable medications. Pergonal and Repronex have considerable contamination with other proteins and therefore are given as intramuscular injections deep into the upper outer quadrant of the gluteus maximus muscle (rear end). Fertinex has been highly purified in the laboratory (through affinity chromatography) so that it can be self administered subcutaneously (under the skin) in the upper thigh or abdomen. Recombinant forms of menotropins (Gonal F and Follistim) are also highly purified since they are the product of genetically reengineered (Chinese hamster ovary) cells grown in culture to produce FSH and these medications can also be administered subcutaneously.
In my experience, the partner of the woman being treated is the most reliable and caring person to give intramuscular injections (the proper technique for preparation and administration of the medication is taught in the office). The shot is given at night (occasionally twice a day) in a dosage that may change from day to day.