Tamoxifen for Infertility

The breast cancer drug, Tamoxifen, is sometimes used in the treatment of female infertility. Also known by its generic name, nolvadex, the medication is part of a drug class known as selective estrogen receptor modulators.

How does Tamoxifen work?

Tamoxifen is used in the treatment of steroid hormone-receptor positive breast cancer. It works by blocking the estrogen receptors in cancer cells, preventing cancer growth and spread.

Fertility specialists sometimes prescribe Tamoxifen for the treatment of female infertility. When administered for this purpose, it works by blocking estrogen receptors in the hypothalamus, the area of the brain responsible for initiating the signal that ultimately leads to ovarian stimulation.

Tamoxifenin the Treatment of Female Infertility

While it may seem strange that a breast cancer drug would be used to treat female infertility, Tamoxifen has been shown to effectively stimulate ovulation in women who do not ovulate on a regular monthly basis. It can also be used to stimulate the ovaries to produce multiple follicles (eggs) in women who are unable to conceive only making one egg per month.

Clomid, or clomiphene citrate, is a common therapy for female infertility associated with ovulatory disorders. Tamoxifenis in the same class of medication as Clomid and works in a similar fashion.  It has been shown to effectively induce ovulation in 65-75 percent of women, a rate similar to that of Clomid. However, in 25-30% of women Clomid can thin the endometrial lining, making it harder to conceive. Tamoxifen does not have this same effect on the uterus.

Tamoxifen Dosage & Administration

Tamoxifenis available in pill form and is usually prescribed as a single daily dose to be taken at the same time each day.This medication should be limited to short term use.

Oral medications, such as Tamoxifen,are less expensive and easier to use than injectable medications designed to stimulate ovulation. For that reason, oral medications are typically first line treatments while injectable gonadotropins are often reserved for use in women who fail to respond to oral medications.

Some side effects of Tamoxifen include:

• Hot flashes
• Nausea
• Dizziness
• Fatigue
• Weight changes
• Headaches
• Hair thinning
• Gastrointestinal upset
• Edema

There is a risk of multiple births associated with Tamoxifen. Talk with your reproductive endocrinologist if you have questions about this or any possible side effects of this drug.