The most common medications used to treat infertility help stimulate ovulation. Examples of these types of medications include:2,3
Clomiphene or Clomiphene Citrate
Clomiphene is a medication patients take by mouth (orally). It causes the body to make more of the hormones that cause the eggs to mature in the ovaries.2 If a woman does not become pregnant after taking clomiphene for six menstrual cycles, a health care provider may prescribe other fertility treatments.
- Patients take clomiphene in the beginning of the menstrual cycle.
- Clomiphene causes ovulation to occur in 80% of women treated. About half of those who ovulate are able to achieve a pregnancy or live birth.2
- Use of clomiphene increases the risk of having a multiple pregnancy. There is a 10% chance of twins, but having triplets or more is rare—less than 1% of cases.2
Letrozole
Letrozole is an oral pill that decreases the amount of estrogen a woman makes, stimulating her ovaries to release eggs.
- Patients take letrozole toward the end of their menstrual cycle for around 5 days.
- A 2015 study by researchers in the NICHD Reproductive Medicine Network found that about 19% of couples with unexplained infertility went on to have a live birth after using letrozole for 4 months. This rate was slightly lower than the live birth rate for couples using clomiphene (23%).4
- Other studies have found that letrozole may work better than clomiphene in women with polycystic ovary syndrome.5
Gonadotropins and Human Chorionic Gonadotropin (hCG)
Gonadotropins such as follicle-stimulating hormone (FSH) are hormones that are injected in a woman to directly stimulate eggs to grow in the ovaries, leading to ovulation.2 Health care providers normally prescribe gonadotropins when a woman does not respond to clomiphene or to stimulate follicle growth for assisted reproductive technology (ART).
- Gonadotropins are injected in the early part of the menstrual cycle for 7 to 12 days.
- While a woman is treated with gonadotropins, a health care provider uses transvaginal ultrasound to monitor the size of the developing eggs, which grow inside tiny sacs called follicles. The health care providers also draw blood frequently to check the ovarian production of estrogen.
- The chance of a multiple birth is higher with gonadotropins than with clomiphene, and 30% of women who conceive a pregnancy with this medication have multiple births.2 About two-thirds of multiple births are twins. Triplets or larger multiple births account for the remaining third.
hCG is a hormone similar to luteinizing hormone that can be used to trigger release of the egg after the follicles have developed.
Bromocriptine or Cabergoline
Bromocriptine and cabergoline are pills taken orally to treat abnormally high levels of the hormone prolactin, which can interfere with ovulation.2 Pituitary growths; certain medications, including antidepressants; kidney disease; and thyroid disease can cause high levels of prolactin.
- Bromocriptine or cabergoline allow 90% of women to have normal prolactin levels.1
- Once prolactin levels become normal, 85% of women using bromocriptine or cabergoline ovulate.1
If disease of the fallopian tubes is the cause of infertility, surgery can be used to repair the tubes or remove blockages in the tubes. Success rates of these types of surgery, however, are low (approximately 20%, depending on the skill of the surgeon).
These surgeries involving the fallopian tubes also increase the risk of ectopic (pronounced ek-TAH-pik) pregnancy, which is a pregnancy that occurs outside of the uterus.1 Ectopic pregnancies are also called "tubal pregnancies," because they most often occur in a fallopian tube.6
Surgery to remove patches of endometriosis has been found to double the chances for pregnancy. Surgery can also be used to remove uterine fibroids, polyps, or scarring, which can affect fertility.