Bioidentical Hormones – A Doctor Answers Basic Questions

by Helene Leonetti M.D.

A handy hormone guide from a physician who answers these questions every day!

Ever since Oprah, Dr. Phil’s wife, and Suzanne Sommers have opened the door onto natural hormone replacement therapy, patients have lined up, dropping even from moonbeams for the coveted nectar to balance our hormones, make us sex goddesses, and turn us into youthful vixens.

May I remind you that I have been using natural hormones (recently dubbed ‘bioidentical’ hormones) for 18 years. My mentor and friend, John R. Lee, MD, began the journey toward a gentler and biochemically astute look at the way our bodies work.

A simple lesson in biochemistry: in order to make this wonderful orchestra whose fine-tuned music gives us balance, we need to remember that cholesterol is the concert master. It is not the evil substance that my colleagues are trying to eradicate with toxic drugs: it is the precursor to all our sex steroids. First in line is pregnenolone, a comet, whose short life prepares the way for the master hormone, progesterone. This powerful substance through God’s magnificent biochemistry converts into testosterone, then into estrogen. Cortisol, produced from our adrenals, the walnut-sized powerhouses that sit atop our kidneys, work with adrenalin and other neurotransmitters, such as norepinephrine to keep our immune system in tip top shape. DHEA is a precursor to testosterone and estrogen, and is important in protein building and repair.

There are three estrogens: estrone (E1), estradiol (E2), and estriol (E3). They are made primarily from the ovary, and are responsible for the growth of female characteristics in puberty and regulating the menstrual cycle. After menopause they are made from androstenedione in fat cells, and muscle cells. In fact, we make estrogen until we die, just in smaller amounts, and regardless if we have a hysterectomy with our ovaries removed.

Although testosterone is a male hormone, which stimulates the growth of male characteristics and the production of sperm, we women produce small amounts in our ovaries.

DHEA is produced primarily in the adrenal glands, and when taken as supplement, can increase testosterone levels as well. It is a marker of aging and can decline dramatically as we grow older.

Bioidentical vs. Synthetic Hormones

Now, what is all this noise about bioidentical hormones and how do they differ from synthetic ones?

Firstly, let me tell you what is NOT bioidentical:

  • birth control pills
  • Depo Provera
  • Nuva Ring
  • Femring
  • birth control patch (Ortho Evra)
  • hormone replacement pills (Premarin and Provera, aka Prempro).

Birth Control – Natural or Not Natural?

There are no natural, bioidentical hormones that we can use for birth control. Condoms, IUDs (non-hormonal, such as the Paraguard), diaphragm and abstinence are all there is. The pill, patch and ring for birth control contain synthetic estrogen (ethinyl estradiol) and a number of synthetic progestins too numerous to list, but suffice it to say, they work for birth control, period. They can regulate erratic menstrual cycles,  but I cannot offer that they enhance vibrant health. They are a convenience for many, and frankly, for women who cannot have boundaries and use the word ‘no’ when they could, to prevent the heart-wrenching experience of an unwanted pregnancy, they serve this purpose.

HRT – Premarin and Provera

To discuss Premarin and Provera, I need to go into the story of how Premarin is produced and the three words ‘pregnant mares’ urine’ can bring us to the realm of how we over the decades have been sleepwalking to our humanity and have used and abused our magnificent horse brothers to make a hormone that only baby horses should be ingesting though breast feeding. The humble soybean has been waiting in the wings to be the precursor to all our ‘bioidentical’ hormones that we are now addressing.

Where to Get Bioidentical Hormones

There are three places to buy bioidentical hormones: a compounding pharmacy, where they prepare a special formulae ordered by a physician; your local pharmacy, and health food stores, to purchase natural transdermal progesterone, the only sex steroid that can be purchased without a prescription from a health care provider (This has been so because of its profound safety, and if used properly has few if any side effects).

I need to remind you that transdermal progesterone is identical to what your ovary produces, as long as the container states USP progesterone, generally 450mg per ounce. Physiological dosing is between 15-20mg once to twice daily. In the women from ages 35-55 who are still menstruating, many of their cycles are an-ovulatory, that is making no eggs, thus no progesterone, I like using the cream twice daily to balance the often excess estrogen. After a woman is postmenopausal (one full year without her period), once daily use is reasonable.

Pharmaceutical bioidentical estrogens available:

PATCH: Menostar, Climara, Vivelle

GELS: Divigel, Elestrin.

SPRAY: Evamist.

PILLS: Estrace

Pharmaceutical bioidentical progesterone:

PILL: Prometrium

CREAM: Crinone (vaginal cream available in very high dose used for infertility)

Compounding pharmacists have special training to provide bioidentical hormone formulae that can include combinations of estriol and estradiol (Biest, generally 80%/20% respectively), Triest (estriol, estradiol, estrone, 80%, 10%, 10%), DHEA, testosterone, cortisol, and melatonin. Most will compound thyroid hormone as well.

Other Hormone Delivery Systems

Other delivery systems for hormones are troches (placed under the tongue and absorbed through the mucous membrane of the digestive system, and pellets (these are injected under the skin and have a prolonged effect (up to three months). My concerns with the former is that the hormone levels peak then fall, and do not have a steady state in the circulation (my bias, to be sure, but my experience as well, though some patients love them), and the latter is problematic if the dosing is incorrect, and the patient has to tolerate the imbalance for the length of effect (many doctors are very skilled in proper dosing, and have an impressive following).

My preference with almost 20 years of experience is the transdermal (through the skin) approach: when we swallow a pill, particularly progesterone, 80-90% gets conjugated and metabolized through the liver, converting to undesirable byproducts that can make us sleepy, drowsy, dizzy. For women who have insomnia, taking this at night is an option. But I must remind you that many women are on drugs, most of which are metabolized through the liver (antidepressants, statin drugs to lower cholesterol, heart, diabetic medicines), and giving the overworked liver another job does not seem sensible, notably because the skin is our most glorious and absorptive organ, and processes the hormones directly into the circulation before going through the liver.

Bioidentical Hormone Safety

Now to safety: bioidentical estrogen is, like synthetic estrogens, such as Premarin, still a stimulating hormone, that, when used alone or in too high dosing, can fuel breast and uterine cancers: the important difference is that when using bioidentical estrogen, we generally use bioidentical progesterone along with it, which is safe enough to give to a pregnant woman, or one with breast cancer; synthetic progesterones (truly, analogs or progestins) such as Provera, are actually more carcinogenic than the estrogen. Because natural progesterone synergizes or works to make small doses of estrogen more effective, the profound safety of the progesterone can neutralize the risk of the estrogen.

Testosterone, the male hormone, in small amounts is produced by the female ovary, and can convert to estrogen, so measuring levels before prescribing is important. I use salivary testing, or blood spot (capillary) testing, and my preferred laboratory is ZRT Lab in Beaverton, Oregon. David Zava, PhD, a biologist and breast cancer researcher, has a world-class laboratory, and his results have assisted me and my colleagues in helping hundreds of thousands of women achieve hormone balance.

Virginia Hopkins, the late Dr. John Lee’s coauthor and editor, has a fine newsletter, Virginia Hopkins Health Watch, where she illuminates topics important to our health and wellness. Like John, Virginia is on the cutting edge of hormone issues and I highly recommend her work.

Note from admin: Please do not post personal medical questions in the comments section.  You can visit Dr. Leonetti’s website to contact her at

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