Clomid/Clomiphene Citrate


Clomiphene citrate, also known by the brand name Clomid or Serophene, is one of the most common medications used to treat infertility. Clomid is an oral medication that is used to promote ovulation.

Clomid is a cost-effective treatment for women that have irregular menstrual cycles, those who don’t ovulate and have been diagnosed with polycystic ovary syndrome (PCOS), or for women that ovulate normally but have been diagnosed with “unexplained infertility.”


Clomid is an orally administered selective estrogen receptor modulator (also known as SERM) that stimulates the release of the hormones FSH (follicle stimulating hormone) and LH (luteinizing hormone) from the pituitary gland. The net effect is to stimulate the ovary to produce one or more eggs.

Since Clomid can result in the ovulation of more than one egg in a month, there is an approximately 5-10% risk of twins and very small risk of higher-order multiples (three or more) with use.


Women that are taking Clomid for ovulation have an 80% chance of ovulating on some dose of the drug, usually within the first three months keeping in mind, clomiphene citrate success rates are often dependent on age. It is important to note that 40% will conceive.

In a study of 4,000 cycles for women taking clomiphene citrate and being treated with intrauterine insemination (IUI) treatment for unexplained infertility, it was found that pregnancy rate per cycle was:

  • 11.5% for women 35-37 years
  • 7.3% in women 38-40 years
  • 4.3% for 41-42 years
  • 1.0% for women over 42

Interestingly, Clomid has been shown in a large multi-center study to be more effective than its “cousin” letrozole (Femara) in the treatment of women with unexplained infertility, whereas the opposite is true in PCOS treatment.


Most women that take Clomid have mild side effects and is generally well-tolerated. Clomid side effects include:

  • Hot flashes
  • Nausea
  • Breast tenderness
  • Mood swings
  • Short lived reversible visual change
  • Nausea

An early small study suggested that women with PCOS who took Clomid for more than one year but not for less than one year, experienced an increased incidence of ovarian cancer. This study has not been reproduced. Some patients may also have thinning of the uterine lining and a decreased production of cervical mucus.