Less common effects (1-10% of people) include visual symptoms (blurred vision, double vision, floaters, eye sensitivity to light, scotomata), headaches, vasomotor flushes (or hot flashes), light sensitivity and pupil constriction, abnormal uterine bleeding and/or abdominal discomfort. Clomifene can lead to multiple ovulation, hence increasing the chance of twins (10% of births instead of ~1% in the general population) and triplets. Some studies have suggested that clomifene citrate if used for more than a year may increase the risk of ovarian cancer. The incidence of fetal and neonatal abnormalities for patients on clomifene for fertility is similar to that seen in the general population. There is no data to suggest a higher rate of congenital anomalies or spontaneous abortions after using this drug. Compared to letrozole, another drug used for ovarian stimulation, a study found no significant difference in the rate of overall abnormalities, but found that congenital cardiac anomalies was significantly higher in the clomifene group compared to the letrozole group. Clomifene is a nonsteroidal SERM that inhibits estrogen receptors in the hypothalamus, inhibiting negative feedback of estrogen on gonadotropin release, leading to up-regulation of the hypothalamic–pituitary–gonadal axis. With the suspension of Cincinnati Reds pitcher Edinson Volquez for performance enhancing drug use and a swirl of rumors that the agent involved was clomiphene (also known as Clomid,) I thought it timely to write about how clomiphene works and how it’s used. From what I read on the internets, there is an enormous amount of misinformation floating around out there. To understand how clomiphene works, you need to know how the pituitary controls the making of testosterone in the testis. Testosterone is made by Leydig cells in the testis, which I explained in my last post. The pituitary releases a hormone called luteinizing hormone (“LH”) that stimulates the Leydig cells to make testosterone. Testosterone is converted to the female hormone estrogen, (which I also explained in my last post,) and estrogen tells the pituitary to stop making more LH. This kind of negative feedback system is common when it comes to how hormones work. As the room gets warmer, the thermostat sends less electricity to the heater.
What is Clomid and how does it work? Clomid is an oral medication that can be used to stimulate ovulation. It works by blocking estrogen receptors at the hypothalamus, which is an important "hormonal control center" for the body. Clomid use for fertility treatment is only recommended if you are not able to get pregnant because of ovulation problems. Most women use this drug with hopes to give birth to twins, but there is just a ten percent chance that this will happen.