Body Identical Hormones

What are “body identical” hormones? Are they the same as “bio-identical hormones”?

There are so many different types of HRT available.  This means that the dose and type of HRT can be altered to suit your individual needs and will also depend on your health and risk factors for other conditions, for example if you have had a clot in the past or have high blood pressure. Many women want to take “natural” products for their menopause but you have to be very careful how you define “natural”. There are many medicines available which are derived from plants, so therefore they are “natural”, but many are unsafe and have been shown to be harmful to your bodies. For example, although black cohosh has been shown to be of some benefit in the treatment of hot flushes, some types of black cohosh have been shown to be associated with liver toxicity.

The oestrogen that I usually prescribe for women is a type of oestrogen called 17 beta oestradiol. This is a “body identical” oestrogen and has the same molecular structure as the oestrogen which decreases in your body during the menopause. It is safer having the oestrogen as a patch or gel as this then is absorbed directly through the skin and has less side effects and risks. These types of oestrogen can be given to women with migraines and those with a higher risk of clot as there is not increased risk of clot using these types of oestrogen. It is also natural in that it is derived from a plant chemical which is extracted from yams, which are tropical root vegetables.

Some types of older HRT contain a mixture of different types of oestrogens and are made from pregnant mares’ urine. So this type of HRT is “natural” but it is not “body identical” as it contains many types of oestrogens that you do not need in your body. This type of HRT is not often prescribed by doctors any more.

There are many different types of progestogens (progestogens is the name for a synthetic progesterone) available for women. If you still have a womb (uterus) it is important that a progestogen is combined with the oestrogen for your HRT. When you take oestrogen the lining of your womb can build up which can increase your risk of cancer. However, taking progestogen completely reverses this risk which means there is no increased risk of cancer when you take HRT.

The type of progestogen I commonly prescribe for my patients is called micronised progesterone (Utrogestan). This is a “body identical” progestogen as it has the same molecular structure as the progesterone in our bodies. This means that is usually is associated with fewer side effects than other types of progestogens. Side effects of progestogens can include bloating, spots and mood swings. Micronised progesterone is also made from yams.

The additional advantage of micronised progesterone is that studies have shown that it is not associated with an increased risk of breast cancer for the first five years of taking it. After this time the risks of breast cancer are very low and seem to be lower than the risk for a woman taking the older types of progestogen.

All these body identical hormones are usually available on the NHS although micronised progesterone is not available in Scotland.

Many private clinics are using “bio-identical” hormones

These are not the same as the “body identical” hormones I have just described to you. These are not regulated and are not subject to any quality control. It is important that you do your research before you commit to anything you buy. Also, check that the HRT is NICE-approved (National Institute for Health and Care Excellence).

These bio-identical hormones are compounded. This means that they are custom made in order to prescribe hormones in combination doses or preparations that are not routinely available.

Some of the hormones used in these bio-identical hormones contain hormones that are not approved for women such as a hormone called DHEA (Dehydroepiandrosterone) or prednisolone. Many women are given progesterone creams which are actually not well absorbed in the body and are not available on the NHS.

Some “natural” progesterone creams for your skin are available in some places over the Internet. These are not recommended as they are not absorbed into the body well and also many contain too little amounts of hormone to be effective.

I see many women in my clinic who have spent considerable amounts of money on these bio-identical products and have experienced numerous side effects. The products used in this way are not regulated or approved and so could potentially be harmful. They have not been subjected to the same tests of safety, efficacy or dosing consistency as the type of HRT that are prescribed to you. In addition, there is no evidence that these compounded hormones have fewer side effects or are more effective that “body-identical” HRT.

In summary, the risks of the hormones you are taking depend on your type of HRT and also your individual risk factors and health. It is very important that you are given the right type and strength of HRT for your individual needs and that the benefits and risks of your HRT are discussed with you by your GP or menopause doctor.

Date updated: May 2018

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