Review Material

Estrous cycle
Menstrual cycle

Prostaglandins
Progestins
Ovulation Induction
Human Infertility

Human Infertility

Ovulation induction medications, often referred to as fertility drugs, are used to stimulate the follicles resulting in the ovulation of one or more oocytes in one cycle.

Protocals control the time of ovulation by administering hCG, so sexual intercourse, intrauterine inseminations, artificial inseminations and in vitro fertilization procedures can be scheduled at the most likely time to achieve pregnancy.

Superovulation is achieved by the dose of the drug given. Ovarian response is monitored with ultrasonography.

The most commonly used drugs are:

Drug Effect
Clomiphene Citrate (Clomid, Serophone) Orally active, synthetic, anti-estrogen. Binds to estrogen receptors on the hypothalmus, reducing the negative feedback from in vivo estrogens so that GnRH is increased leading to increased FSH and LH. Ovulation occurs via normal events. Multiple pregnancy rate is 5% and predominantly twins.
Gonadotropins  
Menotropins (Perganol, Repronex, Follistim, Bravelle and GonalF) Human menopausal gonadotropin (hMG), activity is like a 1:1 combination of LH and FSH. It is administered for 7-12 days to stimulate follicular growth and maturation.
hFSH Human recombinant FSH. It only has FSH activity. Used to stimulate follicular growth and development.
hCG (Profasi, Serono; Pregnyl, Organon; Novarel, Ferring; A.P.L., Wyeth-Ayerst) Behaves like luteinizing hormone (LH) to cause ovulation of follicles. Ovulation occurs 36-48 h after administration.