Body Identical Hormones (Fact Sheet)

What are "body identical" hormones?

Are they the same as "compounded bioidentical” 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 health-needs and risk factors for other conditions, for example if you have had a  blood clot in the past or have high blood pressure. Many women want to take "natural" products for their menopause, but how do you define “natural"? There are many medicines available that derive from plants, so therefore they are “natural", but these are often unsafe and have been shown to be harmful to your bodies. For example, although black cohosh has been shown to have some benefit in the treatment of hot flushes, some types of black cohosh have been shown to be associated with liver toxicity.

Oestrogen treatments

The oestrogen that we usually prescribe for women at Newson Health 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 to have the oestrogen as a patch or gel, as this 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 blood clot, as there is no increased risk of clot using these types of oestrogen. It is also natural because it is derived from a plant-chemical that is extracted from yams - a tropical root vegetable.

Some types of older HRT contain a mixture of different types of oestrogens and are made from pregnant mares' urine. This type of HRT could be described as "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 rarely prescribed by doctors these days.

Progesterone treatments

There are many different types of progestogens (synthetic progesterone) available for women. If you still have a womb (uterus) it is important that a progestogen is prescribed alongside 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 prevents this build-up, which means there is no increased risk of cancer when you take HRT.

 The type of progestogen commonly prescribed at Newson Health 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 it is usually 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 the yam vegetable.

The additional advantage of micronised progesterone is there is no 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 readily available in Scotland.

Many private clinics are using "compounded bioidentical" hormones

These are not the same as the "body identical" hormones just described to you. Bioidentical hormones are not regulated and are not subject to any quality control. It is important to research any menopause treatments before you commit to buying anything - always check that the HRT is approved by NICE (National Institute for Health and Care Excellence).

Bioidentical 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 bioidentical 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 not well absorbed in the body, and not available on the NHS.

Some "natural" progesterone creams for your skin are available over the Internet - these are not recommended, as they do not absorb into the body well and many contain insufficient amounts of hormone to be effective.

We see many women at Newson Health clinic who have spent considerable amounts of money on these bioidentical products, and have experienced numerous side effects. When such products are used in this way they 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 requires a prescription. In addition, there is no evidence that these compounded hormones have fewer side effects or are more effective than “body identical" HRT.

In summary, the risks of the hormones you are taking depend on your type of HRT, as well as 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.


Last updated: June 2019

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