Clomiphene citrate is one of the most commonly used treatments to induce ovulation in women who do not ovulate regularly or who have irregular menstrual cycles. Although it is a widely used drug in reproductive medicine, its mechanism of action, the situations in which it is indicated, and the results that can be expected are not always clearly explained.
How does clomiphene work?
For ovulation to occur, the body must properly coordinate several hormonal signals. Clomiphene acts on this communication system between the brain and the ovaries.
Clomiphene partially blocks the brain's receptors that detect estrogen levels.
Because it does not "perceive" these levels, the brain interprets them as being lower than they actually are and responds by sending stronger signals to the ovaries. As a result, follicular growth is stimulated. In other words, clomiphene "tricks" the body into increasing the production of the hormones necessary for the egg to mature and be released properly, either naturally or as part of a planned cycle.
Clomiphene is particularly useful for women who do not ovulate regularly, such as in many cases of polycystic ovary syndrome (PCOS) or women with very irregular cycles.
When is its use recommended?
Clomiphene is usually the first option in low-complexity treatments when the goal is to induce ovulation. It is used in women who have anovulation, irregular cycles, or in protocols involving timed intercourse and artificial insemination. On the other hand, it is not typically used in women with very low ovarian reserve or in treatments such as in vitro fertilization (IVF), where more precise and powerful stimulation is required.
What results can be expected with clomiphene treatment?
The response to clomiphene is generally good. Most women who use it will ovulate, with success rates exceeding 70%. However, it is important to remember that ovulation alone does not guarantee pregnancy. Factors such as age, sperm quality, the condition of the endometrium, and overall reproductive health also influence the outcome.
Why is monitoring by a specialist necessary?
Although clomiphene is taken orally and may seem like a simple treatment, its use requires proper monitoring to ensure its effectiveness and safety.
Throughout the cycle, the specialist monitors follicular growth through ultrasounds and evaluates how the ovaries respond. This allows for dose adjustments when necessary and helps avoid excessive stimulation.
Having professional guidance is essential to optimize results and decide in a timely manner whether to modify the therapeutic strategy, especially when the desired response is not achieved after several cycles.
Dr. Cristina Guix
Fertility specialist at Barcelona IVF
