Ovulation Induction

Ovulation induction is the term used to describe the use of fertility drugs to stimulate the ovaries to produce a mature egg or eggs.

These medications include:

• Letrozole
• Clomiphene
• Gonadotropin injections

What is Letrozole?

Letrozole is a medication that is used to treat infertility in women who have irregular ovulation or who do not ovulate at all. It works by reducing the levels of estrogen in the body, which can stimulate the release of follicle-stimulating hormone (FSH) from the pituitary gland. This, in turn, can stimulate the ovaries to produce and release eggs. It is typically taken on day 3 to day 7 of the menstrual cycle.

Letrozole is often used as an alternative to clomiphene citrate, another medication commonly used for ovulation induction, as it has fewer side effects and a lower risk of multiple pregnancy.

However, like all medications, letrozole has some potential risks and side effects. The most common side effects include hot flashes, headaches, and nausea. Some women may also experience mood changes, fatigue, or dizziness while taking letrozole. There is an approximately 5% chance of twins using this medicationTop of Form

When to consider Letrozole

Letrozole can be an effective treatment for women with irregular periods or polycystic ovarian syndrome (which is the most common cause for irregular menstrual cycles. Your doctor will determine if you are a good candidate for Letrozole.

What to expect during treatment?

Letrozole is a pill that is taken once per day for 5 days, usually beginning between the 3rd day of your menstrual cycle. If you do not have regular cycles, your doctor may prescribe a medication to induce your period before starting Letrozole.

What is Clomiphene?

Clomiphene (also known as clomiphene citrate & Serophene) is a drug that has been used for nearly 50 years for the treatment of infertility. It was first used to induce ovulation in women who do not have regular periods.

When to consider Clomiphene

Clomiphene can be an effective treatment for women with irregular periods or polycystic ovarian syndrome (which is the most common cause for irregular menstrual cycles). However, Clomiphene is not considered an effective treatment for women over 40. Your doctor will determine if you are a good candidate for Clomiphene.

How does Clomiphene work?

Clomiphene does not stimulate your ovaries directly, but “tricks” your brain into releasing FSH which then subsequently causes ovaries to release one or more eggs.

What to expect during treatment 

Clomiphene is a pill that is taken once per day for 5 days, usually beginning between the 3rd  day of your menstrual cycle. If you do not have regular cycles, your doctor may prescribe a medication to induce your period before starting Clomiphene.

What are the side effects?

The most common complaints are hot flushes, headaches, moodiness, and occasional vaginal dryness. In less than 1 in 1000 cases, some women experience visual disturbances while on Clomiphene. If you experience the visual side effects, you should contact your doctor and discontinue Clomiphene use.

The risk of multiple pregnancy on Clomiphene is between 8-10%, most of which will be twins.

How successful are Clomiphene and Letrozole?

The success of these medications depends very much on your personal situation. If your only problem is that you don’t ovulate (all other testing is normal, including your partner’s semen analysis), they can restore your monthly pregnancy rate to as high as 20% per month, depending on your age.

We generally limit use to about 6 cycles, because if it has not been successful after 6 cycles it is unlikely to improve you chance of pregnancy. Your doctor can discuss the details of these alternatives with you.