Clomiphene citrate, sold under the brand name Clomid among others, is an oral medication used to treat infertility in women. It is the first line treatment for ovulation induction, as well as a diagnostic tool for infertility. Clomiphene is a selective estrogen receptor modulator that acts by blocking estrogen receptors in the brain. This causes the pituitary gland to secrete more follicle-stimulating hormone (FSH) and luteinizing hormone (LH), thereby stimulating ovulation and menstrual cycles.

How Does Clomiphene Work?

Clomiphene works by disrupting the typical feedback loop between the hypothalamus and pituitary glands. Estrogen levels normally provide negative feedback to the hypothalamus, which in turn controls FSH and LH secretion from the pituitary gland. Clomiphene binds to estrogen receptors in the brain and blocks this feedback loop. This results in increased FSH and LH production, stimulating the maturation of follicles in the ovaries. Ultimately, one follicle will become dominant and release an egg, inducing ovulation.

Monitoring Ovulation with Clomiphene

To optimize the chances of conception with clomiphene, ovulation must be carefully monitored through ultrasound and quantitative beta human chorionic gonadotropin (hCG) testing. Ultrasounds are performed periodically throughout treatment to track follicle growth. When the lead follicle reaches a diameter of 18mm or greater, 10,000 to 20,000 units of hCG is administered via intramuscular injection to simulate the body’s natural LH surge and trigger ovulation. Sexual intercourse is ideally timed for the two to three days following hCG administration.

Does Clomiphene Always Induce Ovulation?

While clomiphene citrate successfully induces ovulation in the majority of patients, ovulation does not occur every treatment cycle. Monitored clomiphene cycles result in ovulation approximately 70–80% of the time. Those with polycystic ovarian syndrome (PCOS) have a slightly lower ovulation rate of 60–75%. Factors like body mass index (BMI), age, and previous treatment success impact the likelihood of ovulation. In non-responsive patients, higher doses may be tried or treatment shifted to injectable gonadotropins or assisted reproductive technology.

Potential Side Effects of Clomiphene

Clomiphene is generally well-tolerated, but mild side effects can occur in up to 30% of patients. Hot flashes and vaginal dryness are the most common due to clomiphene’s antiestrogen effects. Other potential side effects may include abdominal bloating, breast tenderness, dizziness, headaches, and temporary vision changes. More rare risks include potentially fatal ovarian hyperstimulation syndrome (OHSS) and multiple gestation if too many follicles are stimulated. Close monitoring is critical, and patients should report any severe symptoms.

Long-term Use of Clomiphene

Currently, there is no consensus on the maximum recommended duration of clomiphene treatment. Typical protocols involve five to six cycles of treatment, though some specialists advocate extending treatment to up to 12 cycles depending on patient age and response. Long-term use beyond one year remains controversial due to theoretical risks to the endometrial lining. However, existing studies have found no increased risk of birth defects even with prolonged use. As with any infertility medication, risks and benefits must be weighed against the patient’s individual circumstances and fertility specialist guidance.

Clomiphene as a Diagnostic Tool

In addition to inducing ovulation, clomiphene can serve a diagnostic role in infertility. If a monitored clomiphene cycle fails to induce ovulation, the probable cause is not tubal pathology or male factor infertility but rather hyperprolactinemia or a hypothalamic hormone imbalance. A clomiphene challenge test can reveal functional hypothalamic amenorrhea due to excessive exercise or weight loss, or premature ovarian failure. A clomiphene-induced rise in estradiol and LH levels generally rules out primary ovarian insufficiency as the infertility cause.

As the oldest and most prescribed fertility drug, clomiphene citrate has helped countless women achieve ovulation and pregnancy. With proper monitoring to track follicular growth and time intercourse, up to 80% of anovulatory infertility patients can experience successful treatment outcomes. As with any medical therapy, potential side effects and risks require shared decision making between medical providers and patients. For most, a short trial of clomiphene provides an effective first line approach in overcoming infertility driven by ovulatory dysfunction.

French German Italian Russian Japanese Chinese Korean Portuguese

Get More Insights On  Clomiphene Citrate 

About Author:

Ravina Pandya, Content Writer, has a strong foothold in the market research industry. She specializes in writing well-researched articles from different industries, including food and beverages, information and technology, healthcare, chemical and materials, etc. (https://www.linkedin.com/in/ravina-pandya-1a3984191)