There are many different types of hormone replacement therapy (HRT) and it can be confusing when there are lots of terms floating around, like “systemic HRT” or “localised HRT.” We wrote this article to help you understand these terms and hopefully be less confused next time you are thinking or talking about HRT. Remember though, to find the most suitable option for your situation, you should always talk to your doctor.
This is when HRT is taken so that the hormones are absorbed into the blood stream and travel around the whole body’s system – hence the name ‘systemic’. Systemic HRT can be taken as a pill, skin patch or gel, or implant. Skin patches and gels are known as transdermal (dermal means skin, so trans-dermal means the HRT is absorbed through the skin). Transdermal HRT is the most common type prescribed. Pills are the second most often prescribed and HRT implants are more rarely used.
The main considerations when doctors prescribe is your past medical history – for example whether you have high blood pressure or have had blood clots in the past*. If this is the case then transdermal or a non-oral HRT is the better option. The reason is that oestrogen absorbed through the skin avoids being processed in the liver, which can increase production of clotting factors. Other reasons to choose transdermal HRT is if you have a BMI of over 30 or have a gut condition that may affect oestrogen absorption from pills.
Some doctors prefer transdermal HRT as this more closely mimics oestrogen delivery before menopause where your ovaries manufacture oestrogen and deliver it directly into the blood stream, avoiding the liver.
If you prefer not to take systemic HRT or can’t take it for a medical reason, localised HRT is often still suitable. Oestrogen is not absorbed into the whole body, instead it acts locally in the vagina and surrounding organs. If you are suffering with vaginal dryness, recurrent UTIs or painful sex, local HRT can improve all these symptoms without needing to take additional progesterone.
These terms refer to the progesterone part of HRT. Cyclical regimes, also known as ‘sequential,’ require taking progesterone for 14 days followed by a 14-day break. This mimics the normal menstrual cycle and during the break you will have a period. Cyclical regimes are preferred in women who are perimenopausal and still having periods.
With continuous HRT regimes, progesterone is taken continuously which stops your monthly periods. Continuous regimes are most suitable when your periods have already stopped for a year i.e. post-menopause. Starting on continuous HRT before menopause may cause irregular bleeding, and lead to uncomfortable and unnecessary investigations.
The easy way to remember the difference between cyclical and continuous regimes is to remember cyclical means bleed (periods), and continuous means no-bleed.
The Mirena coil is a contraceptive and also licensed for use as the progesterone part of HRT. When used around menopause your periods will often stop. The Mirena is the best option if you are perimenopausal and want to start HRT, but don’t want to have monthly periods.
*History of any cancers is very important and suitability for HRT should be discussed thoroughly with your doctor.