Clomifene is useful in those who are infertile due to anovulation or oligoovulation.Evidence is lacking for the use of clomifene in those who are infertile without a known reason. In such cases, studies have observed a clinical pregnancy rate 5.6% per cycle with clomifene treatment vs. 1.3%–4.2% per cycle without treatment.

Clomifene has also been used with other assisted reproductive technology to increase success rates of these other modalities.

Clomid can be initiated at a dose of 50 mg daily for 5 days, starting on cycle day 3, 4, or 5 (where cycle day 1 is the first day of the menstrual period), thus being taken on cycle days 3-7, 4-8 or 5-9. During a clomifene-induced cycle, there should be frequent intercourse (every other day) the week before and including the estimated day of ovulation, (cycle days 9-18). If LH surge detection tests are used, these tests should be started 3 to 4 days after the last clomifene tablet is taken (that is, if taking clomifene on cycle days 4-8, LH surge tests should be started on cycle day 11) and continue until ovulation is indicated (that is, the test becomes positive.) or through cycle day 18. If there is no spontaneous surge, there may be an artificial triggering of oocyte release if there is an ovarian follicle of over 20 mm in size, such as by an intramuscular injection of 10,000 units ofhCG. However, routinely using oocyte release triggering with hCG appears to decrease pregnancy chances compared to frequent monitoring with LH tests.

The following procedures may be used to monitor induced cycles:^[4]

• Follicular monitoring with vaginal ultrasound, starting 4-6 days after last pill. Serial transvaginal ultrasound can reveal the size and number of developing follicles. It can also provide presumptive evidence of ovulation such as sudden collapse of the preovulatory follicle, and an increase in fluid volume in the rectouterine pouch. After ovulation, it may reveal signs of luteinization such as loss of clearly defined follicular margins and appearance of internal echoes.
• Serum estradiol levels, starting 4-6 days after last pill
• Post-coital test 1-3 days before ovulation to check whether there are at least 5 progressive sperm per HPF
• Adequacy of LH surge by urine LH surge tests 3 to 4 days after last clomifene pill
• Mid-luteal progesterone, with at least 10 ng/ml 7-9 days after ovulation being regarded as adequate.

Repeat dosing: This 5-day treatment course can be repeated every 30 days. The dosage may be increased by 50-mg increments in subsequent cycles until ovulation is achieved. It is not recommended by the manufacturer to use clomifene for more than 6 cycles.

It is no longer recommended to perform an ultrasound examination to exclude any significant residual ovarian enlargement before each new treatment cycle