What Are The Side Effects Of Hormone Replacement Therapy For Menopause?

The hormones used in hormone replacement therapy (HRT) can cause side effects, just like any drug. Usually, most side effects improve with time, but it's a good idea to persevere with care if possible for at least 3 months. If you have serious side effects or they persist for more than 3 months, talk to a doctor.

Side effects of Oestrogen

The main side effects of taking oestrogen include:

• bloating
• breast tenderness or swelling
• swelling in other parts of the body
• feeling sick
• leg cramps
• headaches
• indigestion
• vaginal bleeding

After a few weeks, these side effects will also pass. Try: To ease the side effects:

• Taking a dose of oestrogen with food can help with feelings of illness and indigestion.
• Eating a low-fat, high-carbohydrate diet that reduces the tenderness of the breast
• Doing daily exercises and stretching to help with leg cramps

Your GP may suggest switching to a different form of taking estrogen (for example, switching from a pill to a patch), adjusting the medication you are taking, or lowering your dose if side effects continue.

Side effects of Progestogen

The main side effects of taking Progestogen include:

• breast tenderness
• swelling in other parts of the body
• headaches or migraines
• mood swings
• depression
• acne
• tummy (abdominal) pain
• back pain
• vaginal bleeding

As with oestrogen side effects, these will normally pass within a couple of weeks. A GP may suggest moving to another method of taking progestogen, changing the medication you are taking, or lowering the dose if they continue.

HRT-related health risks

Although the risk of some debilitating diseases is reduced by HRT/MHT, it can increase the risk of others. These small risks must be balanced against the individual woman's benefits from HRT. Chat about any issues you may have with your doctor.

Breast cancer and HRT

Women over the age of 50 who have been using combination estrogen and progestogen (progesterone) substitutes for less than five years have little to no increased risk of developing breast cancer. There is a significantly elevated chance for women who use combined HRT for more than five years. Women with oestrogen alone have no increased chance of being used for up to 15 years.

There is no indication that if a woman with a family history of breast cancer uses HRT, she would have an additional elevated chance of developing breast cancer. The risk of oestrogen and progestogen combination is higher than that of oestrogen alone or newer HRT agents such as tibolone (sold as Livial or Xyvion) and can also depend on the form of progestogen used. Studies show that there are higher risks for medroxyprogesterone acetate and norethisterone than for dydrogesterone and progesterone.

Cardiovascular disease and HRT

Women over 60 on combined oral (tablet) HRT have a minor increased risk of developing heart disease or stroke. While the risk increases are small, they need to be taken into consideration when beginning HRT, as the risk arises early in care and continues over time. When used in tablet form, but not when using a skin patch, estrogen used on its own raises the risk of stroke further. Likewise, from the mid-60s, tibolone raises the risk of stroke in females. There is a lower risk of cardiovascular disease for women who start HRT during the average time of menopause than for women aged 60 or older.

Ovarian cancer and HRT

There is a very slight increased risk of ovarian cancer and an estimated one extra case per 10,000 HRT users per year. HRT was related to two forms of tumours in a recent review: serous and endometrioid cancers.