Fertility drug could be the cause of birth defects and miscarriages

• A drug used to increase a woman's chances of becoming pregnant may cause birth defects and miscarriages, according to a safety alert issued Monday by Canadian health regulators.
• The drug letrozole, marketed under the brand name Femara, is approved to treat breast cancer in women who've undergone menopause.
• But doctors in the United States and Canada often prescribe it "off-label" to prompt ovulation as part of fertility treatments.
• Health Canada, the government national health care agency, and Swiss drug maker Novartis have sent letters to Canadian doctors warning them about the off-label, or unapproved, use of the drug.
• Femara's official FDA prescribing information targeted at doctors warns that the drug may harm the fetus when prescribed to pregnant women, citing studies in rats.
• "If there is exposure to letrozole during pregnancy, the patient should be apprised of the potential hazard to the fetus and potential risk for the loss of pregnancy," the warning states.
• While the FDA and Health Canada approve drugs as safe and effective for certain treatments, doctors can prescribe drugs any way they see fit.
• Fox said that Novartis doesn't know how many women have received the drug as an unapproved infertility treatment.
• A third patient had a baby diagnosed at the age of 1 with a type of cancer, called neuroblastoma.
• A female baby born to a fourth patient, who received Femara as a cancer treatment while pregnant, was diagnosed with a genital abnormality.
• There also are seven cases in which the outcome of the babies is unknown, while two patients had normal babies at delivery, Vlk said.
• Also prompting Health Canada's action was a recent presentation by Dr. Marinko Biljan at the International Conference on Reproductive Medicine in Montreal, which noted an increased rate of birth defects born to mothers treated with the drug at his clinic.