How clomiphene works
The chemical structure of clomiphene is very similar to estrogen. When clomiphene is taken, the drug fills up all the estrogen receptors on the pituitary gland, and "fools" the brain into thinking that the estrogen level in the blood is very low. The pituitary gland then responds to this low estrogen signal by secreting extra amounts of the hormones LH and FSH. LH (luteinizing hormone) and FSH (follicle stimulating hormone) are the two hormones that stimulate the ovary to produce eggs.
How clomiphene is taken
Clomiphene is a tablet, taken by mouth, once a day for five days. You may be on 1, 2 or 3 tablets per day, depending on your prescribed dosage. (50 mg. per tablet) The tablets (if more than one per day) should all be taken at one time, at approximately the same time each day. The time of day is not critical. Clomiphene can be started on cycle day 3, 4 or 5. -
Monitoring the cycle
Studies have shown that some patients may have persistent ovarian cysts. Thus, a baseline ultrasound may be performed. If cysts are present, we may wait a month for them to resolve or try birth control pills to suppress them. Five days after the last pill, you will need to come to the office for an ultrasound. During this ultrasound examination, we will look at your ovaries to determine how they have responded to the clomiphene. The ultrasound will show how many follicles (the fluid-filled sacs that contain the eggs) are developing on each ovary, and what size they have grown to be. If the follicles are "mature" (large enough), the next step will vary depending on your course of treatment:
hCG (human chorionic gonadotropin), also called Novarel is an injection that will help the follicles release the eggs. Please bring in your Novarel (vials of drug and diluent) when you have your ultrasound exam. We can give you the injection or teach you how if it must be given at a later time. Basically, you will use 2 cc’s of the diluent to dissolve all of the power and inject this into the hip.
You should plan to have intercourse the day of the ultrasound, and again every other day for approximately one week. Eggs are viable (able to be fertilized) for roughly 24 hours after ovulation, and sperm for about 48 to 72 hours after ejaculation into the vagina.
If you do not get pregnant, you may take clomiphene again the following month. You should always call in to check with one of the nurses before starting the pills, however, as Dr. Donahue may want to suggest a change in dosage or timing of the drug. If you have not conceived within three rounds of treatment, we suggest you make a consultation appointment with Dr. Donahue, to review your treatment, and discuss future options. Several other drugs may be added to clomiphene which have been shown to improve pregnancy rates. For instance, glucophage (metformin) twice daily; estrace , 2 mg day 3-12; or dexamethasone , .25 mg day 3-12 are some of the adjunct therapies we use.
Side effects of clomiphene
Adverse reactions to clomiphene are relatively uncommon. Reported side effects (along with their frequency) are as follows: *ovarian enlargement (1 in 7 patients) *hot flushes (1 in 10 patients) *abdominal discomfort (1 in 15 patients) *twins (1 in 10 patients) Others (experienced by fewer than 1 in 50 patients) include: mood swings, breast tenderness, nausea, insomnia and visual disturbances.
Results and success rates with clomiphene
Pregnancies following clomiphene treatment usually occur at the lower
dosages of 50 or 100 mg per day, and within the first three or four
attempted cycles. Generally, we do not go beyond six cycles. Baseline
ultrasounds may be done to exclude ovarian cysts which may affect the
pregnancy rates. Pregnancies do occur at higher dosages and at later
cycles, but this is not the norm. Clomiphene carries about a 10% multiple
pregnancy rate (less than 1% of all deliveries are triplets or more).
Birth defects following clomiphene use occur at a rate no higher than that
seen in the general population.