PCOS, Clomid and Letrozole...oh my!
Traditionally, Clomid have been used to induce ovulation for women with PCOS. Clomid was discovered decades ago and is considered an “old champion” of ovulation induction. The ovulation rates for Clomid are reasonable, however because Clomid is an anti-estrogen in the cervical mucus and uterine lining, pregnancy rates are about 10-15% per ovulation induction cycle.
Another medication for ovulation induction, Letrazole, has been available for more than 10 years. However, the use of this drug was discouraged when one study suggested the link between using Letrazole for ovulation induction and birth defects. The study was poorly planned and heavily criticized, but the concern remain valid for some time.
Recently a new study was published in the New England Journal of Medicine. The study compared live birth rates of patients with PCOS who used Letrozole or Clomid to induce ovulation and to get pregnant. The study demonstrated that women who received Letrozole also had a higher ovulation rate (61.7% vs. 48.3%) than those who received Clomid. Another important finding was that women who received Letrozole had live births of about 27.5% while women who received Clomid had live birth of about 19%. Letrazole was noted to be more efficient that Clomid for women with PCOS.
During this recent study, no significant differences in birth defects, pregnancy loss or twin pregnancies were noted between the groups that received Clomid or Letrazole. This recent study suggests that Letrozole is a safe and efficient medication that can be used as a first line treatment for women with PCOS who are trying to conceive.