Treat breast cancer and preserve fertility
Most of the chemotherpay drugs used in the treatment of breast cancer causes infertility in women undergoing treatment for breast cancer. It was not clear whether the new hormonal drugs would retain fertility. Now it is clear that at least one of them does retain fertility. A study published in the American Journal of Obstetrics & Gynecology, confirms that women who took Letrozole (Femara) alone or with injectable fertility medications, preserve fertility and were just as likely to conceive and remain pregnant as those who took other ovulation stimulators, and more likely to achieve pregnancy than those on placebo. In addition the researchers also noted that the women who took Letrozole had "a significantly lower rate of multiple gestation compared with clomiphene citrate (Clomid)," which is one of the most popular first-line treatments for ovulation stimulation.
"The risks to women and their babies associated with multiple gestation pregnancies just can't be overstated," notes Dr. Mark Leondires, MD, a board-certified endocrinologist and medical director at Reproductive Medicine Associates of CT. Multiple gestations are linked to increased rates of premature birth, birth defects and a host of other maternal-fetal issues. In fact, a November 2004 data review by the Centers for Disease Control shows that the pregnancy-related death rate in the U.S. is approximately 8 per 100,000 for singleton pregnancies; for multiple gestations - from twins to sextuplets and beyond - the rate more than quadruples, to nearly 37 per 100,000. "So, when a drug like Letrozole shows so much promise in addressing the challenge of anovulation successfully, while reducing the incidence of multiple gestations associated with other drugs, the reproductive community gets excited," Dr. Leondires adds.
Another study shows that Letrozole can be less costly and can require lower doses of medications than other first-line treatments as well. In the September, 2004 Journal of Social Gynecologic Investigation, researchers found that lower doses of Follicle Stimulating Hormone (FSH) were needed to induce ovulation in women with PCOS when Letrozole was administered in combination with FSH, as opposed to administering FSH alone. "Whenever we can reduce the amount of medication needed to achieve a desired result, there is a benefit," Dr. Leondires explains. "In addition to cost-effectiveness, we also achieve a better quality of life for the patient when we can lessen the frequency or amount of medication she needs to take."
Ovulation disorders can be categorized two ways - oligo-ovulation is the term for infrequent ovulation, while anovulation is the term for a complete lack of ovulation. Both conditions are usually caused by hormone imbalances, stemming either from malfunction of the hypothalamus and/or pituitary glands, or from a disease called Polycystic Ovarian Syndrome. While researchers are unsure of its exact mechanism, Letrozole seems to restore ovulation by blocking the enzyme in women that converts male hormones (androgens) to female hormones (estrogens). "It is possible that this restores a better hormone balance in women with ovulation disorders," Dr. Leondires confirms. "This seems to help secondary aspects of their infertility as well," he adds. "For example, women in some Letrozole studies have shown thicker endometriums at mid-cycle, which is associated with a better chance for implantation of the fertilized egg."
The same hormone-neutralizing action that makes Letrozole effective as a fertility medication is responsible for its popularity as a breast cancer drug. It has been used safely for a number of years in women with postmenopausal "estrogen-receptor" breast cancer. "Letrozole is giving so many women new hope," Dr. Leondires notes. "Just as this drug has helped women overcome breast cancer, we believe that it will continue to provide help to millions of women who struggle with the inability to achieve a healthy pregnancy and delivery," he concludes.