Dr. John Studd
clinical gynaecologist
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Bioidentical Hormones

There seems to be a view that the use of bioidentical hormones is a clever American development that is a vital advance on orthodox HRT. It is important to realise that bioidentical hormones in the form of oestradiol, testosterone and progesterone has been used in Europe, particularly France for at least 20 year and I have used nothing else during this time. Meanwhile our American colleagues had been obsessed by the use of oestrogens extracted from urine of pregnant mares; conjugated equine estrogens (Premarin) and were most reluctant to move on to the more appropriate preparations of human hormones. Premarin contains about 64 different equine hormones and 20% of Godknowswhat. In contrast, oestradiol is the natural human oestrogen that is the most active in the body.

There is also good evidence that oestradiol through the skin is safer and probably more effective than when taken by mouth. If oestradiol is taken as an oral tablet it is changed in the gut and the liver to a less effective oestrogen Oestrone, whereas the transdermal route of oestradiol whether by gels, patches or implants produces the appropriate level of oestradiol in the blood stream.

There is also clear evidence that by using transdermal oestradiol stimulation of coagulation factors from the liver is avoided whereas this does occur as the result of the first pass effect with the ingestion of oral oestrogens.


Testosterone is a normal female hormone and is present in 5-10 times the amount in the adult female as oestradiol. It is a vital hormone necessary for mood, energy and libido and it is certainly best given through the skin as gels or implants. There is a license to use testosterone patches in women who have had a hysterectomy. In my view gels or implants are preferable.
DHEA (Dehydroepiandrosterone) is often considered a bioidentical hormone and is freely available in many countries. It is a precursor of testosterone and has only one fiftieth of the potency of testosterone. Although it is useful it is more sensible to use transdermal testosterone which is clearly bioidentical than taking tablets of DHEA and more effective.


The problem with bioidentical hormones comes with the progestogen components. The much heralded expensive progesterone cream available on the internet with exaggerated claims of increase in bone density and improvement of depression, hot flushes, sweats, etc is in fact virtually ineffective as it is hardly absorbed. My team have spent more than £100,000 studying this preparation over the last few years and it has no effect whatsoever on bone density, no effect upon mood and no effect upon the symptoms of flushes, sweats and headaches which are the common symptoms of the menopause. It might have a tranquilising and sedating effect if it is absorbed. These results have been published in Menopause International (Benster et al)

It is therefore necessary to give an effective progesterone/progestogen to protect the lining of the womb in patients receiving oestrogens. Most gynaecologists would use a synthetic progesterone such as Norethisterone or Medroyxprogesterone which certainly protects the uterus and produces regular scanty periods. Unfortunately, it often reproduces PMS symptoms in those women who are progesterone intolerant and therefore there is a move to use a more natural progesterone such as Utrogestan 100 mgs for 7 days of each calendar month. This is in contrast to the orthodox management of 14 days of progestogen a month because of the frequent problems of depression, breast discomfort and loss of energy that occurs with a longer course of progestogen in those women with PMS and progestogen intolerance.

The best method of taking bioidentical hormones would in my view be Oestrogel 2-3 measures daily with the possible addition of transdermal testosterone gel and then Utrogestan 100 mgs daily for the first 7 days of each calendar month. This would bring about a regular scanty bleed on about the 10th day of each calendar month. You will find more details of this treatment for menopausal symptoms, hormone responsive depression and osteoporosis in this web site but please remember that it is not a recent American discovery. That would be too much to bear!

August 2012