Part 1: Bioidentical Hormone Therapy vs Conventional Hormone Therapy

Are all hormones created equally? Simply put, no.

The data is now clear that there are some hormones used in hormone replacement therapy that are better than others. That starts with the type of hormone molecules that are used, either bioidentical or not-bioidentical, with our preference being bioidentical.


Both Bioidentical Hormone Therapy (BHT) and Conventional Hormone Therapy (CHT) fall under the general umbrella of Hormone Replacement Therapy (HRT). The difference is how closely the hormone molecules used mirrors our own body's hormones. Namely we are talking about the type of estrogen and progesterone used. Bioidentical hormones are molecularly very similar to the hormones that our bodies naturally produce. Conventional hormones are mostly synthetically made or derived from biological sources such as horse urine and less-closely resemble our body’s own.


Does this matter? Absolutely, each tiny change in structure changes how that molecule interacts within our body. Therefore, each type of hormone molecule has different benefits (efficacy) and risks (side effects) associated with it.


Bioidentical Estrogens include:

  • Estrone 

  • Estradiol 

  • Estriol

  • 17-Beta estradiol

  • Estradiol acetate

  • Estradiol hemihydrate


Estrogens used in CHT, that are not bioidentical:

  • Esterified estrogens

  • Conjugated estrogens

  • Conjugated equine estrogens


Bioidentical Progesterone includes:

  • Progesterone (or micronized progesterone)


Progesterone-like compounds used in CHT, that are not bioidentical:

  • Medroxyprogesterone acetate

  • Norethindrone acetate

  • Levonogestrel


(If you are on a non-compounded HRT product and are wondering if it is bioidentical, click here to find out. HRT made by compounding pharmacies are almost always bioidentical)


The Most Well Known Hormone Replacement Therapy Study, The WHI Study

The most extensive and well-known study done on HRT safety was completed between 1993 and 2002 and is called The Women’s Health Initiative Study, commonly referred to as the WHI study. The WHI was one of the most far-reaching clinical trials of post-menopausal women's health ever undertaken in the US. As part of this project there was a subset of women (approximately 30,000 women) who were part of the HRT trial. The trial was stopped in 2002 as the women who were on non-bioidentical HRT were found to not have the benefits the trial was looking for and an increased risk of side effects, like breast cancer and cardiovascular disease. This is why hormone replacement therapy got a bad reputation. Of course, these are very serious risks. But here is where there is an important thing to note - None of the hormones used in the WHI study were bioidentical, which makes a BIG difference.


Estrogen used in WHI was conjugated equine estrogens (CEE) made from pregnant mare urine and the progesterone used was a synthetically made progesterone, medroxyprogesterone acetate. Women were either on estrogen alone (in the case of women who had previously had a hysterectomy) or were on a combination of both the estrogen and progesterone. Some women were also on oral estrogen which is a practice we now know to avoid, as taking estrogen orally is what increases the risk of blood clots.

A word on the increased risk of breast cancer in WHI. It is important to look at the increase in absolute risk as well as relative risk. There was a statistically significant in relative risk between the women on HRT and those not on HRT. However, you have to look at this in the context of absolute risk. The group that was on non-bioidentical HRT had an increase equivalent to 1 extra breast cancer case per 1,000 women. This resulted in a AR of 4/1000 women in non-hrt control compared to 5/1000 women in the HRT group. An important point is also that there was NOT an increase in mortality in the group on hormones even with the increase in breast cancer risk.

So the question is, can we really apply what we learned from the WHI to bioidentical hormones? No. Different molecules, different risks, and different benefits. This is NOT to say that bioidentical hormones come with no risks. But we have strategies to make sure that the risks are minimized such as:

- Use the lowest amount needed to obtain the women's goals for a symptom free perimenopause or menopause 

- Use bioidentical versions of hormones

- Use a combination of estradiol and estriol

- Never dose estrogen orally (*sublingual is okay)

- Start HRT early (in perimenopause or at the beginning of menopause)

- Support estrogen processing/metabolizing pathways

Our goal at Remedy is to help women feel their best and use hormones safely. After all, women nowadays are now living almost half their life in their perimenopause/postmenopause state!

The immediate benefits of HRT on the woman suffering from hot flashes are non-debatable and somewhat easy to obtain. The art of adjusting hormones to relieve symptoms such as anxiety, insomnia, weight gain, low libido, and many many other are more nuanced and are where we shine! We help doctors formulate personalized ratios of estradiol, estriol, DHEA, progesterone and testosterone to help you feel like yourself again. 

If you want to get more info on getting started or feel that your current regimen isnt being managed optimally please contact one of our pharmacist specialists today. We also offer hormone testing kits that can be purchased here. These come with a consultation with the pharmacist and also recommendation on BHRT that can be sent to your doctor. 

By April Segal, PharmD, BCPS, APh

Remedy Pharmacist + Founder