Clomiphene 101: Get To Know Your Fertility Drugs.
Clomiphene is a fertility drug used to stimulate ovulation. It is prescribed to women who ovulate irregularly or not at all.
So how does Clomiphene work? Each little pill contains a weak estrogen-like hormone that acts on the endocrine system to increase levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). (See Know Thy Cycle Part II to understand the roles of FSH and LH in ovulation). Increased levels of FSH improve the chances of growing an ovarian follicle to maturity and triggering ovulation.
Sounds like a pretty amazing drug for those women whose tests show that they are not ovulating. For those with PCOS who do not ovulate regularly Clomiphene can be a great option.
But lets take a closer look at its effectiveness. According to the American Society of Reproductive Medicine, Clomiphene will induce ovulation in about 80% of women, and between a third and two-thirds of those will get pregnant within 3-6 cycles.
But what do those numbers really look like? Take 100 women: 80 will ovulate after taking Clomiphene, and at best 53 women will get pregnant within 3-6 cycles. That leaves 47 of those initial 100 women without a desired pregnancy. It’s by no means a “magic pill” that works for everyone.
Interestingly, Clomiphene does not appear to increase the chances of pregnancy in women who ovulate regularly but have not conceived for over a year and are therefore categorized as suffering from unexplained infertility. Other women who are also unlikely to respond are those with absent periods and low estrogen levels due to low body weight or exercise (called "hypothalamic amenorrhea"). Nor does it seem Clomiphene has an effect on those women with high follicle-stimulating hormone (FSH) levels- an indicator of ovarian "aging."
So what should you expect if you’re taking Clomiphene? One study found that 77.8% of women reported at lease one side effect from taking the drug. Irritability, feeling down, and bloating were reported in high frequencies. The American Society of Reproductive Medicine found the most common complaints in their research were hot flashes (60% of women), mood swings (44%) and headaches (31%).
And don't forget that with increased ovulation comes an increased risk of multiple births. Approximately 6 % of women who use clomiphene have twins, and 0.5 percent have triplets or greater.
The highly respected Cochrane Gynaecology and Fertility Group suggests you find a doctor who is willing to monitor your Clomiphene treatments using ultrasound. This allows for them to choose the appropriate dose of clomiphene in subsequent cycles and to minimize the side effects and risks of hyperstimulation and/or a multiple birth pregnancy.
Clomiphene is a great option when infertility is due to pathologies of ovulation. However, be sure to fully understand the side effects and monitor your expectations throughout each treatment cycle.