Why Isn’t Letrozole Working? What to Investigate When You’re Still Not Ovulating

If you’ve gone through multiple rounds of Letrozole and you’re still not consistently ovulating—or you’re ovulating but still not getting pregnant—you may be wondering:

Why isn’t Letrozole working for me?

Maybe your dose has already been increased. Maybe you’ve been told to try another round. Or maybe the conversation has already shifted toward IUI or IVF.

But there’s another question I want you to ask:

Why isn’t my body ovulating consistently in the first place?

Letrozole is commonly used in fertility treatment to induce ovulation. It works as an aromatase inhibitor, temporarily reducing estrogen production in a way that can stimulate the body to produce the hormones needed for follicle development and ovulation. Pasted markdown

But not every woman who isn’t ovulating has the same underlying fertility picture.

And when Letrozole isn’t working, I don’t want to simply keep looking at the ovulation itself.

I want to start investigating why ovulation isn’t happening.

1. Look at Your Full Reproductive Hormone Picture

One of the first things I want to understand is your actual hormone pattern.

That means looking beyond estrogen or a single progesterone result and considering markers such as:

• Estradiol
• FSH
• LH
• Prolactin
• Total and free testosterone
• SHBG
• DHEA-S

Why?

Because anovulation is not a diagnosis by itself.

A woman with PCOS may not be ovulating for a very different reason than a woman experiencing hypothalamic amenorrhea or another form of ovulatory dysfunction.

For example, in the women I work with who have a history of restrictive eating, under-fueling, over-exercising, or chronic physiological stress, I often want to investigate whether we’re seeing a low-estrogen, low-FSH and low-LH pattern rather than assuming PCOS is the explanation.

Your hormone pattern helps us start distinguishing between these different scenarios.

2. Stop Looking at TSH Alone

Another area I want to investigate when Letrozole isn’t working?

Your thyroid.

And I don’t mean simply checking TSH and moving on because it landed inside the standard reference range.

Your thyroid and reproductive system are interconnected, which is why I want a more comprehensive understanding of thyroid function when a woman is struggling with ovulation and infertility. Pasted markdown

This becomes even more important if you’re also experiencing symptoms such as:

Feeling cold all the time.

Hair loss or thinning.

Brittle hair and nails.

Constipation.

Fatigue.

Poor energy.

If you’ve been told, “Your thyroid is normal,” based solely on TSH while experiencing several of these symptoms, I would want to investigate further and look at a full thyroid panel, including in addition to TSH, free T3 and T4, total T3 and T4, reverse T3 and thyroid antibodies.

3. Investigate Nutrient and Mineral Status

Next, I want to understand whether your body actually has the nutritional resources it needs to support reproductive function.

You can eat an incredibly “healthy” diet and still have a history of eating too little for your body’s needs.

This is especially relevant if you’ve spent years dieting, restricting carbohydrates, exercising intensely, maintaining a very lean body, skipping meals, or simply not realizing how much fuel your body actually requires.

In my practice, we may use comprehensive bloodwork alongside tools such as a Hair Tissue Mineral Analysis (HTMA) to add additional information about nutritional and mineral patterns.

Rather than adding another five fertility supplements because someone on TikTok told you to, I want to understand your individual picture and what your body uniquely needs to restore fertility, and to thrive.

4. Connect Your Symptoms Instead of Treating Them Separately

This may be the biggest shift I want you to make.

Your lack of ovulation isn’t happening in a vacuum.

I want to know about your history with birth control.

Your history with dieting.

How you’re currently eating.

How much you’re exercising.

Your stress levels.

Your sleep.

Your digestion.

Your energy.

And I especially want to know about symptoms you’ve possibly dismissed as unrelated.

Maybe you’re waking up to pee between 2 and 4 a.m.

You’re bloated or constipated.

Your hair is thinning.

You’re freezing all the time.

You crash every afternoon.

You feel simultaneously exhausted and wired.

Your libido has disappeared.

Those details matter because they allow us to start connecting the bigger fertility picture rather than treating your inability to ovulate as an isolated problem.

So What Should You Do If Letrozole Isn’t Working?

I want you to shift the question from:

“What dose of Letrozole should I try next?”

to:

“Why am I not ovulating in the first place?”

There may be multiple factors contributing to your fertility picture, and identifying your individual pattern can help you understand what deserves your attention next.

And that’s exactly why I created the Why Aren’t You Ovulating? Quiz.

Instead of spending another night Googling your symptoms and wondering which piece applies to you, this free quiz will ask you questions about your specific situation and help you identify the pattern that may be worth investigating next. Pasted markdown

Ready to figure out why you may not be ovulating?

👉 Take the free Why Aren’t You Ovulating? Quiz and find out what I’d focus on next.