Clomiphene triggers the brain's pituitary gland to secrete an increased amount of follicle stimulating hormone (FSH) and LH (luteinizing hormone). This action stimulates the growth of the ovarian follicle and thus initiates ovulation.
During a normal menstrual cycle only one egg is ovulated. The use of clomiphene often causes the ovaries to produce two or three eggs per cycle. Clomiphene is taken orally for 5 days and is active only during the month it is taken.
Clomiphene Citrate for ovulation induction
Clomiphene used in conjunction with a medication called Provera may be effective in initiating menstruation and ovulation in women who have no menstrual cycle:
- Treatment begins with a 5-7 day course of Provera, taken orally.
- Two to three days after Provera is completed, a menstrual period should begin.
- On the 3rd, 4th or 5th day of menstrual flow, a course of clomiphene is started.
- A clomiphene citrate 50 mg tablet is taken orally for 5 days.
- On day 11 or 12 of the menstrual cycle, ultrasound monitoring is conducted to determine if an ovarian follicle or follicles have developed. Also at this time, patients are asked to use an ovulation predictor kit to test their urine for a surge in LH (luteinizing hormone) indicating that eggs have matured and ovulation is imminent. If no LH surge is detected, ovulation itself may be triggered with an injection of the medication hCG (Ovidrel), which will cause the release of the mature egg(s) from the follicle(s).
- Natural intercourse or insemination is timed to ovulation.
- If ovulation has been assisted by an hCG injection, a form of the hormone progesterone is given via vaginal tablets or gel. The progesterone hormone serves to support the endometrial (uterine) lining and prepare it for the fertilized egg.
Two weeks after ovulation, patients are asked to take a home pregnancy (urine) test. If the test is positive, a blood test will be performed to confirm results.