Dr. Mylinh Vo, ND, ABAAHP • Anti-Aging & Bio-Identical Hormone Specialist Since 1997

The Use of Bio-Identical Hormones

What are Natural Hormones?

Natural or bio-identical hormones are hormones which are chemically identical to the hormones produced by the human body since birth. Specifically, they are synthesized in the laboratories from the sterols (fat) of wild yam and soy plants. For those of you who are sensitive to soy and soy products, the sterols have been highly purified so that no residue from the plant is left in the finished product and it is the protein portion of soy that triggers allergic reactions, not the sterols; so, there’s no need to worry about allergies to natural hormones. 


Why Natural Hormone Replacement Therapy?

  • Synthetic or unnatural hormones metabolize to stronger, hard-to-process foreign products while natural hormones metabolize to natural metabolites which the human body recognizes and knows what to do with them.
  • Natural progesterone has been shown to prevent endometrial cancer and reduce breast cell hyperplasia (abnormal changes) while Progestin (synthetic progesterone) do not.
  • There are many disturbing side effects with synthetic estrogen products such as thrombosis (blood clots), gallstones, headaches, impaired glucose tolerance, increased risk of endometrial cancer, increased growth of existing uterine fibroids, continued menstruation, fluid retention, breast tenderness, depression, nausea, dyspepsia, increased blood pressure, fibrocystic breasts, increased risk of breast cancer, weight gain, etc…
  • Bio-identical hormones are more efficient in preventing and reversing vaginal atrophy associated with peri-menopause or menopause and reducing or preventing urinary and vaginal infections.
  • Natural hormones also prevent and reverse osteoporosis, enhance libido
  • Estriol (E3) may help prevent cancer – it does not promote proliferation of the endometrial lining in the uterus
  • Natural progesterone has been shown to protect against osteoporosis, endometrial hyperplasia, genital atrophy, surgical menopause, anxiety and depression disorder, etc…
  • Natural hormones combine with hormone receptor sites and elicit biological effect without many of the undesirable side effects that are seen with the synthetic forms
  • Natural hormones do provide relief of the symptoms associated with menopause, including hot flashes, night sweats, vaginal atrophy, mood swings, depression, palpitations, skin tone, and more


Hormone Assessment

Because hormones have powerful effects on the body, special care should be followed when you are taking any hormone prescription. For Dr. Vo to fully assess whether you have a hormonal imbalance issue, you will be asked to:

  • fill out various comprehensive questionnaires for thyroid, adrenal, and sex hormone dysfunction assessment (a very comprehensive way to review your hormone-related symptoms)
  • participate in a hormonal physical exam so the doctor can screen for any physical signs of hormonal dysfunction problems
  • do a blood and/or salivary test to get a baseline level of your hormones
  • repeat the blood and/or salivary test a few months after the initialization of hormone treatment to assess treatment efficacy and evaluate your new hormone levels. Patients who are taking hormone supplements should have their hormone levels in the blood or saliva evaluated at least once yearly. Your needs for hormones and your body’s ability to process the hormones do change from time to time.

Routes of Bio-Identical Hormone Administration

Oral: Any hormone administered orally is exposed to the gastrointestinal tract. There is evidence that absorption can be adversely affected by local disease and by disruption of the bowel flora. Concurrent antibiotic administration is a common cause of break-through bleeding in women on combined estrogen-progesterone regimens. Improper bowel flora may also reduce estrogen bioavailability by interfering with enterohepatic (gut-liver) recycling of estrogens. The oral route of hormone administration has long been considered impractical because of poor absorption and short biological half life. However, contrary to traditional teachings, recent researches confirm that significant serum hormone levels can be achieved with new modification in the preparation of hormones for oral administration, including micronization and dissolution in oils consisting of principally long-chain fatty acids. The oil-base hormones can be compounded from Dr. Vo’s prescription by a licensed pharmacist using FDA approved ingredients. Further more, Dr. Vo always works with her patients to support her patient’s gastrointestinal tract and liver functions to maximize the proper utilization and metabolism of all hormones given.


Transdermal: In the case of the estrogen patch, the estradiol is carried across the plastic membrane by the ethanol gel that the estradiol is dissolved in. It then diffuses along a gradient through the layers of the skin to be absorbed by the dermal capillaries in the skin. Creams work essentially by the same mechanism, but the alcohol is mixed with the cream. Transdermal hormone blood levels are lower than oral hormone blood levels.


Subcutaneous Implants: These were developed because it was determined that some women require higher plasma levels of hormones. A main problem with implants is that the plasma levels of hormones rise rapidly, remain constant for around 4 months, then decline gradually. Menopausal symptoms return and women report that the implant has “run out”. If re-implantation occurs, some women then rebound with supra-physiological levels of hormones. Symptom-free intervals become shorter and shorter and new implants become less and less effective.


Vaginal: vaginal hormones are prescribed mainly to relieve symptoms of the lower genital tract (for example, vaginal estrogens). They are available as either creams, gels, or pessaries. Systemic absorption occurs through the vaginal lining.


Sublingual: The hormones are absorbed by the capillaries (tiny blood vessels) under the tongue, thereby they avoid this first pass via the portal vein to the liver.


There are still much to know about the effects of long term uses of natural hormones. Therefore, I monitor doses and hormone levels closely when I prescribe hormone therapy to my clients. Once the patient has been evaluated thoroughly, I can team up with her to customize a treatment regimen for her and her unique biochemistry. All options should be considered and discussed in great details. The reasons to be on hormones should be identified clearly. The length of treatment and how frequently the patient’s hormone levels should be evaluated will be determined; all based on the individual patient’s case history.


I have treated many women over the years with various menstrual disorders, bleeding disorder, menopause, subfertility issues, etc…By utilizing the most comprehensive hormone questionnaires, hormone testing (blood and/or saliva), and extensive case history taking, I can properly diagnose, assess and treat various hormonal disorders using proper diet and lifestyle changes, nutrient supplementation, herbal therapies, homeopathic remedies, and natural hormones to restore the physiological and biochemical balances in my patients. The treatment plan is always comprehensive and individualized based on the patient’s needs. The principle “First, Do No Harm” is always my guiding principle when it comes to prescribing medications to patients. Unless indicated otherwise, I prefer to use the minimal amount of hormones necessary to balance the endocrine systems. It’s important to review other bodily systems like the liver and the gastrointestinal tracts to make sure all hormones, vitamins, nutrients are properly processed. It’s crucial to be sure not only does my hormone and nutrient therapies are working for the patients in relieving their symptoms but also the patient’s body can metabolize these hormones and nutrients effectively. The ultimate goal is to turn on the body’s innate healing ability and to use only what’s minimally necessary to activate this healing power in each patient.

By Dr. Mylinh Vo, ND, ABAAHP