What Does Letrozole Do for Fertility?

If you’re exploring fertility treatments, you’ve probably come across Letrozole. Maybe your doctor recommended it. Maybe someone on a forum swears by it. Either way, you’re wondering: what exactly does Letrozole do—and can it really help me get pregnant?

At fertie, we’re here to make things clear, compassionate, and actionable. Whether you’re trying to ovulate naturally or starting a treatment cycle, here’s everything you need to know about Letrozole and how it works.

What Is Letrozole?

Letrozole (brand name Femara) is a medication originally used to treat hormone-sensitive breast cancer. But today, it’s widely prescribed for fertility—especially in women with PCOS, irregular cycles, or unexplained infertility.

Letrozole works differently than Clomid, and many fertility doctors now recommend it as a first-line treatment for ovulation induction.

How Does Letrozole Work for Fertility?

Letrozole is part of a class of drugs called aromatase inhibitors. In short, it lowers estrogen levels temporarily—just enough to signal your brain to act.

Here’s how it supports ovulation:

• Lower estrogen tells the brain to release more FSH (follicle-stimulating hormone)

• FSH stimulates your ovaries to grow follicles (each containing an egg)

• Once the follicles mature, ovulation can be triggered—either naturally or with medication

In other words: Letrozole helps your body ovulate when it isn’t doing so regularly on its own.

Who Is Letrozole For?

Letrozole is commonly prescribed if you:

• Have PCOS and aren’t ovulating consistently

• Have unexplained infertility

• Haven’t responded well to other medications (like Clomid)

• Are doing IUI (intrauterine insemination)

• Need a lower chance of multiples (compared to Clomid)

Your doctor might also suggest Letrozole in IVF prep if you're doing a mild stimulation protocol.

How Do You Take Letrozole?

Most Letrozole cycles are simple:

• Dosage: 2.5mg to 7.5mg per day

• Timing: Taken on Cycle Days 3–7 or 5–9 (your doctor will confirm your protocol)

• You may have ultrasound monitoring to track follicle growth

• Some cycles include a trigger shot or ovulation predictor kits to time intercourse or IUI

The goal is to develop one or more mature follicles, time ovulation accurately, and increase your chances of conception.

Success Rates with Letrozole

Letrozole is effective—especially for women with PCOS.

• 60–80% of women ovulate regularly on Letrozole

• Many conceive within 3–6 cycles

• Lower risk of twins or multiples (under 5%) compared to Clomid

It's one of the most trusted medications in early fertility treatment.

Are There Side Effects?

Letrozole is generally well-tolerated. That said, some people experience:

• Headaches

• Fatigue

• Dizziness

• Mood changes or hot flashes

Most side effects are mild and temporary. And unlike Clomid, Letrozole has less impact on cervical mucus and uterine lining, which may improve pregnancy rates in some cases.

Personal Insight: What It Was Like to Take Letrozole

“I was diagnosed with PCOS at 32 and hadn’t ovulated in months. My doctor prescribed Letrozole, and by the second cycle, I was ovulating regularly. I liked that the side effects were minimal—and I didn’t have the mood swings people talk about with Clomid. By the third cycle, I was pregnant with my son.”
— fertie Community Member

Final Thoughts

Letrozole can be a powerful and effective tool—especially if you’re navigating PCOS, irregular cycles, or unexplained infertility. It works by gently nudging your body toward ovulation, with a high success rate and a generally low side effect profile.

Whether you’re starting your first cycle or trying a new approach, the key is knowing what to expect—and feeling supported along the way.

👉 Inside our Fertility 101 course, we walk you through medications like Letrozole in detail, with guidance from fertility doctors, real stories, and practical tools to help you feel confident and prepared at every step.

Because your fertility journey is yours—and you deserve support that meets you exactly where you are.

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Disclaimer: Prices and treatment protocols vary by clinic and individual. Always consult with your fertility specialist for accurate, up-to-date pricing and guidance tailored to your situation.