Letrozole is one of two different medications (the other one being Clomid) that can be prescribed to folks who need support with their fertility.

It’s often the first treatment for folks with irregular menstrual cycles as it can encourage your body to ovulate.

It’s now the first choice over Clomid as it’s been shown to be more effective with fewer side effects.

How does Letrozole work?

Letrozole is a drug given to people as a way to induce ovulation.

It works by decreasing the amount of oestrogen that your body makes. This tells your body that it needs to produce follicle-stimulating hormone (FSH), which encourages the body to ovulate.

This treatment is really useful for folks with PCOS (polycystic ovarian syndrome) and for folks who experiences irregular cycles or cycles where they don’t ovulate.

How to use Letrozole

Letrozole is usually started on Day 3 or 4 of your cycle, where Day 1 is the first full day of your bleed. You take the medication for 5 days, once a day and you will normally ovulate four to seven days after you’ve stopped taking the medication.

For folks who don’t menstruate, you can start taking the medication anytime.

It’s common to use Letrozole for up to six months.

Is Letrozole effective for fat folks?

In a study in 2011, 90 people were given Letrozole followed by an IUI. The study compared pregnancy rates between those with a BMI of less than 30 and those with a BMI of over 30.

The study showed that pregnancy occurred in 10.4% of the patients with a lower BMI and in 18.2% of the patients with a higher BMI and that the odds increased with BMI.

Although the study stated that these results were not statistically significant, I think it’s a pretty great result for fat bodies, especially when I hear so many stories from clients that they are being denied Letrozole based on their BMI.


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So why are people being denied Letrozole based on their BMI?

The most common reason I hear from clients is that fertility clinics don’t want to help them due to increased risks during pregnancy.

There are 3 BIG THINGS wrong with this reason.

  1. It is your body. You have the right to decide what risks you are willing to consent to. Only you have the right to decide what is an acceptable risk versus the possible benefit. If you are fully aware of the increased risks during pregnancy then you should be able to consent to treatment.
  2. The evidence around risk during pregnancy is often sensationalised. Doctors will speak of increased risks in a very scary way, making you believe that you are sure to get these complications during pregnancy. A classic example is Gestational Diabetes – If you BMI is 18-25, your risk is 2.3%. If your BMI is over 35. your risk is 11.5%. This is a big jump but it still means that 88.5% of people with high BMIs don’t get Gestational Diabetes.
  3. The evidence that we do have is not clear cut. Science is only as good as the people who do it. Humans are biased and as such, the research can often lead to these biases informing conclusions. There are some papers which show a correlation between higher risk and BMI and there are some that show no correlation. So many of the research papers don’t take into account the lived experience of fat people which includes other factors such as weight cycling, current dietary restriction and weight stigma, all of which we know negatively impact how fat people experience the healthcare system.

If Letrozole may help you to become a parent, then it should be your decision to have this treatment.

Image of medication with title Letrozole for Folks with Higher BMI