Letrozole may help women with PCOS become pregnant

pregnancy, pregnant woman
Photo by Bianca de Blok.

The drug letrozole results in higher birth rates in women with polycystic ovary syndrome (PCOS) than the current preferred infertility treatment drug, according to a nationwide study led by Penn State College of Medicine researchers.

PCOS affects 5 to 10 percent of reproductive-age and is the most common cause of female infertility. Women affected have excessive levels of the hormone androgen, have infrequent periods, develop small cysts on the ovaries and have trouble conceiving.

Clomiphine citrate—a drug that stimulates ovulation—has been the standard treatment for decades.

"Clomiphine has its drawbacks," said Richard Legro, professor of obstetrics and gynecology and lead author on the study. "It's only 22 percent successful with up to six cycles of treatment in producing a successful birth, it has a high multiple-pregnancy rate in comparison to unassisted conception, and it has side effects including and mood changes."

Letrozole is a class of drug that blocks estrogen production.

To compare the two drugs, researchers studied 750 with PCOS between 18 and 40 years old who wanted to conceive. Women were randomly assigned to either clomiphene or and took the medications for up to five cycles, with increasing dosage each cycle. Results are reported in today's (July 9) issue of the New England Journal of Medicine.

The group of women who received letrozole had a higher rate of live births—27.5 percent—than those on clomiphene—19.1 percent. In addition, ovulation rates were significantly higher with letrozole than with clomiphene at each monthly visit.

Fewer twin pregnancies occurred in the women who took letrozole—3.9 percent on letrozole and 6.9 percent on clomiphene. Clomiphene was associated with a significantly higher incidence of hot flashes; letrozole with significantly higher incidence of fatigue and dizziness. Birth defects were rare and rates were similar between the two medications, comparable to those from studies of women who conceive without treatment.

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

Is egg freezing an empowering option for women?

Nov 17, 2014

Katie Hammond, a PhD candidate in the Department of Sociology researching the experience of egg donation in Canada, discusses the recent decision by tech giants Facebook and Apple to offer egg freezing to ...

Peripheral nerve blocks OK for migraines in pregnancy

Nov 14, 2014

(HealthDay)—For migraines that do not respond to medications, peripheral nerve blocks may be a treatment option in pregnant women, according to research published online Nov. 5 in Obstetrics & Gynecology.

Hearing the heart of the mother and her baby

Nov 14, 2014

A group of students from the Autonomous Metropolitan University of Mexico (UAM-I) developed a technological portable prototype able to diagnose health conditions in the mother and in the baby by monitoring ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.