Femara (letrozole) is a brand-name oral tablet that your doctor may prescribe off-label for infertility. The drug is not approved for this use, but it has been shown to be helpful in treating infertility.

Femara belongs to a drug class called aromatase inhibitors. The medication is available in a generic version.

Read on for more information about Femara. You can also refer to this other article for a comprehensive look at Femara and its approved uses.

Note: The Food and Drug Administration (FDA) has approved Femara to treat certain forms of breast cancer. In some cases, your doctor may prescribe Femara off-label for infertility. Off-label drug use is when an FDA-approved drug is prescribed for a purpose other than what it’s approved for.

Doctors define infertility as an inability to become pregnant after 12 months of regularly having sex without using birth control. A couple may experience infertility if either partner has a problem with their reproductive health.

Infertility in females* is most commonly caused by a problem with ovulation (the release of eggs from the ovaries). For example, you may ovulate irregularly or not at all.

Symptoms of ovulation problems can include having irregular periods or no periods at all.

The most common cause of ovulation problems is polycystic ovary syndrome (PCOS), a condition in which cysts develop on your ovaries, leading to changes in your hormone levels and menstrual cycle.

* Sex and gender exist on spectrums. Use of the term “female” in this article refers to the sex assigned at birth.

Who Femara is prescribed for

Femara is mainly prescribed for females with infertility caused by ovulation problems. In some cases, it may be prescribed for females with infertility that doesn’t have a clear cause.

Your doctor will determine whether taking Femara off-label for infertility is safe for you.

You should not take Femara for infertility unless your doctor has prescribed the drug for this purpose. The use of Femara for infertility is considered an off-label use. Off-label drug use is when a medication the FDA has approved is prescribed for a purpose other than what it’s approved for.

Femara treats infertility by inducing ovulation (causing your ovaries to release an egg). For this use, you’ll take the medication for 5 days at the start of your menstrual cycle.

The way Femara works

Femara works by temporarily reducing your estrogen levels. This causes your pituitary gland to release two hormones: follicle-stimulating hormone (FSH) and luteinizing hormone (LH). FSH stimulates an egg to mature in your ovaries, and LH triggers the egg to be released.

When you ovulate, you have a higher chance of conceiving through having sex or through undergoing intrauterine insemination (IUI), which is also called artificial insemination.

How long does it take for Femara to work?

Ovulation usually happens around 5 to 10 days after you’ve taken your last Femara tablet. For details, see the “Taking Femara” section later in this article.

Femara is an effective treatment for inducing ovulation. This can help you become pregnant either through having sex or through undergoing IUI.

Letrozole (the active ingredient in Femara) is recommended as a treatment option in guidelines on the management of infertility.

The success rate of Femara for fertility treatment can depend on several factors, including the cause of your infertility, your overall health, your age, and whether you’re taking or receiving any other treatments.

To learn more about your chances of conceiving with Femara, talk with your doctor.

For fertility treatment, your doctor will usually prescribe Femara for a few days at the start of your menstrual cycle. This induces ovulation.

Ovulation usually happens about 5 to 10 days after you’ve taken your last Femara tablet. Your doctor will recommend that you have sex or undergo IUI around this time.

Signs of ovulation can include changes in your body temperature and in the color and thickness of your vaginal discharge. But your doctor will usually recommend using an ovulation predictor kit to help you know when you’re about to ovulate. They may also use ultrasound scans to monitor the development of eggs in your ovaries.

If you’re trying to conceive naturally, your doctor will recommend when and how often you should start having sex. If you’re undergoing IUI, your doctor will recommend when you should go to your clinic for the procedure.

Dosage

The usual Femara dosage for fertility treatment is 2.5 milligrams (mg) once per day for 5 days. In some cases, your doctor may prescribe 5 mg or 7.5 mg once per day for 5 days.

Your doctor will usually recommend starting Femara on day 3 or 5 of your menstrual cycle. Day 1 of your menstrual cycle is the first day of your period.*

Be sure to follow your doctor’s instructions on how to take Femara for fertility treatment.

* If you’re not having periods, your doctor will tell you when to take Femara.

Note: In addition to being prescribed off-label for infertility, Femara is approved by the FDA for certain uses. Keep in mind that the drug’s dosage may differ with these approved uses. To learn more, see this article about Femara and dosage or talk with your doctor.

How to take

Femara comes as an oral tablet. You can take it either with or without food.

You should take Femara around the same time of day on each of the 5 days that you take the tablet. This helps the medication work effectively.

How often to take

You should usually take Femara once per day for 5 days at the start of your menstrual cycle. But be sure to follow your doctor’s instructions for taking Femara.

If you don’t become pregnant with the first cycle of treatment, your doctor may prescribe more cycles. It may take 1 to 6 cycles of treatment to get pregnant.

If you haven’t conceived after 6 treatment cycles, your doctor likely won’t prescribe additional cycles because it’s unlikely that Femara will work for you. You can talk with your doctor about other options you may have for fertility treatment, including other fertility drugs.

The off-label use of Femara for infertility may cause side effects that are mild or serious.

The lists below include some of the main side effects reported with Femara when used off-label for infertility.

For information about other potential side effects of the drug, talk with your doctor or pharmacist. You can also refer to this Femara side effects article or view the drug’s prescribing information.

Note: After the FDA approves a medication, it tracks and reviews side effects of the drug. If you develop a side effect while taking Femara and would like to inform the FDA, visit MedWatch.

Mild side effects

Mild side effects of Femara when used off-label for fertility treatment can include:

These side effects of Femara may be temporary, lasting a few days to weeks. But if they last longer, bother you, or become severe, it’s important to talk with your doctor or pharmacist.

Serious side effects

Serious side effects of Femara when used off-label for fertility treatment can include:

Call your doctor right away if you develop serious side effects while taking Femara. If the side effects seem life threatening or you think you’re having a medical emergency, call 911 or your local emergency number immediately.

Allergic reaction

For some people, Femara can cause an allergic reaction. But this side effect was not reported in the drug’s clinical trials.

In general, symptoms of allergic reaction can be mild or serious.

Ways to manage

For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep taking the medication.

For severe allergic reaction symptoms, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening.

If you’ve had a serious allergic reaction to Femara oral tablet, your doctor may recommend taking a different medication instead.

How much Femara costs is based on several factors. These can include your prescribed treatment regimen, the insurance plan you have, the pharmacy you use, and your location.

Femara is a brand-name drug that’s also available as a generic version called letrozole. Brand-name drugs usually cost more than generics.

Your doctor can advise you on whether the generic is safe for you to take off-label for infertility. If it is, they can also help determine whether the brand-name drug or the generic is right for you. To learn about the generic form, talk with your doctor.

You can also refer to this Femara cost article for details.

To save money on your Femara prescription, explore these coupons from Optum Perks. (Optum Perks is a sister site of Medical News Today.)

Before your doctor prescribes Femara off-label for infertility, there’s some important information to keep in mind. The drug may not be a safe option for you if you have certain medical conditions or other factors that affect your health. Some of these are mentioned below.

Off-label drug use is when a drug is prescribed for a purpose other than what it’s approved for.

If any of the following medical conditions or other health factors are relevant to you, talk with your doctor before taking Femara:

Here are the answers to some frequently asked questions about taking Femara for fertility treatment.

Are there certain foods to avoid while taking letrozole (Femara) for fertility?

No, there are no specific foods you should avoid when taking Femara for fertility treatment. If you have questions about eating specific foods while taking Femara, talk with your doctor.

For general information about what to avoid while taking Femara, including other medications, see this article about Femara interactions.

Is Femara better for infertility than Clomid?

It might be, although this may depend on the cause of the infertility.

Femara and Clomid are both used to induce ovulation as part of fertility treatment. Clomid is no longer available, but doctors may prescribe a generic version of the medication, which is called clomiphene citrate.

In people with infertility related to PCOS, studies show that Femara has a higher success rate for fertility treatment than Clomid. In this group of people, the risk of multiple pregnancies, such as twins, is also lower with Femara than with Clomid.

However, in people with unexplained infertility, a review of studiesTrusted Source found Femara and clomiphene to have similar success rates for fertility treatment. This review also found the drugs to have a similar risk of twin pregnancies.

Talk with your doctor about whether Femara or clomiphene is a better treatment option for you.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.