7 Little-Known Facts About Hormone Replacement Therapy (HRT)

Menopausal hormone therapy (HRT) is the single most effective treatment for hot flashes, night sweats, and dry and painful sex. It can also help preserve bone mineral density, help preserve cognitive function and promote cardiovascular health.

And yet, less than 5% of American women aged 50-59 use it. Sadly, they (and their doctors) are still confused or not up-to-date with its nuances.

• The Why: A 2002 study led people to believe that HRT could lead to breast cancer and heart disease. While the findings have been retracted conclusively, the fear and misinformation stuck.

That’s like suffering with a splitting headache and never touching the Advil in your cabinet because someone told you once it might be dangerous.

So,  let’s get clear on what we actually know.

1) There’s a “window of opportunity.”

Timing matters with HRT. Starting within six years of your final period, or before age 60, is associated with a lower risk of heart disease compared to starting later.

• Science Says: A study with 643 women found that those who started estradiol within 6 years of menopause had slower artery wall thickening (a marker of heart disease). But those who started estradiol 10 years after menopause saw no difference.

Doctor’s Note: This doesn’t mean you can’t start after this window. It just means it’s a more individualized discussion with your doctor about risks and benefits.

2) Estrogen alone can lower breast cancer mortality.

Remember that study that scared everyone from hormone therapy?

Well, 20 years later, researchers revisited those same women. They found that women who’d had a hysterectomy and used estrogen-only HRT had FEWER breast cancers and LOWER  breast cancer deaths than those on placebo.

This is the opposite of what most women have been told for decades.

3) Not all progestogen is created equal.

If you have a uterus, you need progesterone alongside estrogen to protect your uterine lining. But the type of progesterone changes your risk profile.

• Medroxyprogesterone Acetate (MPA): A synthetic progestin. It’s been linked to a slightly higher risk of blood clots.
• Micronized Progesterone: This bioidentical form is chemically similar to what your body makes. A 2015 study found there was no increased risk of blood clotting.  

4) How estrogen gets into your body matters.

When it comes to deciding between pills, patches, or creams, your delivery method matters more than you realize.

Oral estrogen (pills) has a higher risk of thrombosis since it goes through your liver first. Meanwhile, transdermal estrogen (patches and gels) absorbs directly into your skin and bypasses the liver, reducing your chance of blood clots.

• Doctor’s Note: If you’re at higher risk for blood clots, transdermal is often the safer route.

5) Progesterone is not optional.

As I mentioned earlier, if you have a uterus, and you take systemic estrogen, you need progesterone because estrogen stimulates the uterine lining. Without progesterone, that unchecked growth could lead to endometrial cancer.

In other words, progesterone is a safety requirement.

6) Breast cancer survivors can use vaginal estrogen.

Many women assume breast cancer means all estrogen is off-limits. Not true! Low-dose vaginal estrogen can be used safely because it stays local and very little gets absorbed into your bloodstream.

So if you’ve been treated for breast cancer, there’s NO reason you need to suffer with vaginal dryness, frequent UTI’s or painful sex. Ask your doctor about vaginal estrogen!

7) “Bioidentical” is both a chemistry and marketing term.

FDA-approved estradiol and micronized progesterone are bioidentical. They’re well-studied and regulated.

But the term “bioidentical” has also been hijacked by marketing. When you see it advertised, it usually refers to compounded custom-mixed hormones from specialty pharmacies. That said, there are pharmaceutical-grade bioidentical HRT options that are safe, effective and regulated.

• Zoom In: Compounded hormones should only be used in rare situations when no approved option fits, because dose consistency and safety data are limited. ACOG is explicit on this and I agree.

Looking to Get On HRT?

If you’re thinking, “Maybe I should get on HRT,” great! Here’s how you can move forward:

1. Get Specific. Bring up to your doctor your age, time since menopause, uterus status, personal and family history, migraine pattern, blood pressure, and venous thromboembolism (VTE) risk. These factors will tailor your plan.
2. Ask About Formulation. Match the molecule and the route to your goal. For most, it’ll be transdermal estradiol plus oral micronized progesterone. But if you don’t have a uterus, estradiol alone could be a good option.
3. Set Expectations. HRT treats symptoms and preserves function, especially bone. But it is not a forever cardiology prescription for everyone, and it’s not a beauty serum.

Lastly? Zoom out. Remember that the biggest things you can control to lower midlife breast cancer risk are alcohol, maintaining a healthy weight, and staying active. HRT decisions should live within that larger conversation about sleep, strength training, nutrition, and community.