Clomiphene Citrate (Clomid®, Serophene®) has been available since 1968 and is commonly used for women who have infrequent periods or long menstrual cycles. It is in pill form and is taken for 5 days at the beginning of the menstrual cycle. It works by preventing estrogen from binding to estrogen receptors and gives the body the false impression that estrogen levels are low. This causes your body to produce more FSH (follicle stimulating hormone), which will result in the growth of follicles in the ovary. It is the follicle that contains the egg.
Side effects include nausea, headaches, mood swings, vaginal dryness and hot flashes. In some patients, Clomiphene Citrate can decrease cervical mucus and cause thinning of the endometrial (uterine) lining. Complaints of visual disturbances may necessitate stopping the medication. 90% of women who are going to conceive with clomiphene do so in the first 3-4 cycles of taking this medication and for this reason it is recommended not to use Clomiphene Citrate more than 4 cycles.
Clomiphene Citrate may be very effective in women who do not ovulate and women under the age of 35. Women’s ovaries tend to become more resistant to Clomiphene Citrate as they age and for this reason more effective medications such as HMG (human menopausal gonadotropin) and FSH (follicle stimulating hormone) are considered for use in women over 35 with infertility.