HRT and Fibroids: How Are They Affected?

Women may wish to consider using HRT during their perimenopause or menopause to manage their menopausal symptoms and a common concern for women is whether they can use HRT if they have fibroids and whether this will make their bleeding pattern worse.

While evidence suggests that HRT may affect fibroids, it is not strictly contraindicated. With careful selection of the type and dosage, HRT can still be an option for women with fibroids. In this article, we explore fibroids in greater depth and examine the use of HRT for managing menopause symptoms in women who have them.

What are fibroids?

Fibroids are non-cancerous (benign) growths of smooth muscle and fibrous tissue that grow in the wall of the womb (uterus). They are sometimes referred to as uterine myomas or leiomyomas (3).

Fibroids most commonly develop in women between the ages of 30 and 50 years and are sensitive to the hormones oestrogen and progesterone.

They are common, with one in every 2 or 3 women having at least one fibroid, and are often found incidentally (for example, when under medical investigation for another reason) (3). The incidence of fibroids increases with age and peaks in the perimenopausal years, and declines after menopause (1).

The size of a fibroid can vary from pea-sized to the size of a tennis ball or even bigger. It is common to have more than one fibroid, and they can develop anywhere in the womb. The main types of fibroids are:

Intramural fibroids: These are the most common type of fibroid and develop in the muscle wall of the womb. They can cause heavy and painful periods by interfering with the constriction of blood vessels during menstruation (2).
Subserosal fibroids: These develop outside the wall of the uterus into the pelvis. They can grow significantly. They normally do not cause symptoms even when relatively large. When they are sufficiently large they may cause symptoms due to pressure on adjacent structures, for example pressure on the bladder can lead to increased urinary frequency.
Submucosal fibroids: These occur in the muscle layer beneath the womb’s inner lining and grow into the cavity of the womb. Even small submucosal fibroids can cause heavy and painful periods or reduce fertility.

Subserosal and submucosal fibroids can sometimes attach to the womb with a narrow stalk of tissues. These are known as pedunculated fibroids (3).

What causes fibroids?

The exact cause of fibroids is not known but they have been linked to the hormone oestrogen. It’s believed this is why they usually develop during a woman’s reproductive years when oestrogen is at its highest and tend to shrink after menopause when oestrogen levels are naturally lower (3).

There are risk factors that are associated with the development of fibroids which include:

Increasing age - The risk of fibroids increases with age during reproductive years until the menopause
Starting your period early - risk of fibroids increases if periods start before the age of 11
Never having given birth
Older age at first pregnancy
Obesity - in particular central obesity and weight gain
Family history - risk of fibroids is higher in women who have an affected first degree relative

There are variations in frequency of fibroids between different ethnicities. The risk of fibroids is higher in black and Asian women compared to white women and more more likely to be symptomatic, occur at an earlier age, be larger and multiple in these ethnic groups.

Symptoms of fibroids

Fibroids do not often cause symptoms, and many women will not even be aware that they have them. Symptoms that do occur are influenced by the location, size and number of fibroids (4) and can include:

Heavy and painful periods

Fibroids can cause heavy menstrual bleeding (menorrhagia), often leading to periods that last longer than usual or frequent bleeding between periods (5). Painful cramps during menstruation are also common and may become severe, interfering with daily activities. These symptoms occur because fibroids can increase the size of the uterine lining or disrupt the normal contraction of the uterus. Intramural and submucosal fibroids are most likely to be associated with painful periods.

Anaemia

Chronic heavy bleeding from fibroids can lead to iron deficiency anaemia, leaving you feeling fatigued, weak, or dizzy. In severe cases, anaemia may cause shortness of breath or heart palpitations, requiring medical attention (6).

Pelvic pressure

Fibroids can grow large enough to press against surrounding organs, causing a feeling of fullness, heaviness, or pressure in the pelvic area (4). This discomfort may worsen when standing, sitting for long periods, or during certain physical activities, including intercourse. Larger fibroids are more likely to cause noticeable pressure.

Urination issues

Fibroids that press on the bladder may lead to urinary symptoms such as frequent urination, difficulty emptying the bladder fully, or in some cases, incontinence (4).

Bowel issues

When fibroids exert pressure on the rectum, they can cause constipation, straining during bowel movements, or even rectal discomfort (7). Larger fibroids may also contribute to a sense of incomplete evacuation after using the restroom, making bowel issues a persistent problem. Subserous fibroids are most likely to cause pressure symptoms such as constipation.

Pain

Pain from fibroids can occur in various forms, including sharp, stabbing sensations or persistent dull aches. Some women experience pain during intercourse or lower back pain if fibroids press on surrounding nerves (4, 5). This symptom can significantly affect intimacy and mobility.

Fertility issues

Fibroids can interfere with conception by blocking the fallopian tubes or altering the shape of the uterine cavity, making it difficult for an embryo to implant (8). Submucosal fibroids, in particular, are linked to reduced fertility because they distort the endometrial lining.

Pregnancy complications

Rarely, fibroids can increase the risk of complications during pregnancy, such as preterm labour, miscarriage, or abnormal positioning of the baby (8). They may also contribute to heavier bleeding after delivery or make caesarean delivery more likely, depending on their size and location.

Diagnosis of fibroids

Fibroids are usually diagnosed following a pelvic examination or an ultrasound scan. As they often don’t cause symptoms, some fibroids are only discovered during routine gynaecological examinations or investigations for other issues (13). They do not necessarily require any treatment unless they cause symptoms or are large.

If an ultrasound scan suggests you have fibroids, you may be referred to a gynaecologist for further investigations such as a hysteroscopy, laparoscopy and/or biopsy (13).

Can HRT cause fibroids?

Fibroids often shrink in size after the menopause as a result of the fall in the levels of oestrogen hormone after the menopause. Women who take HRT are less likely to have a reduction in the size of their fibroids as fibroids would be sensitive to the replaced hormones oestrogen and progesterone. There may be a small increase in the size of their fibroids but this effect is unlikely to be significant as the level of hormones supplied through HRT is less than that in natural cycles. HRT is not associated with the development of new fibroids. Therefore, having fibroids would not be a contraindication to receiving or continuing with HRT (11).

HRT isn’t associated with the development of new fibroids, but it can cause fibroids to grow or increase in number, specifically in the first two years of use. One study found that after three years of using HRT, fibroid volumes decreased significantly to similar levels as measured at baseline (9).

The best HRT for fibroids

When managing menopause with fibroids, the best type of HRT depends on the size and symptoms of the fibroids, as well as your overall health and requires an individualised approach with an expert clinician.

We would recommend starting with the lowest dose of oestrogen and reviewing bleeding pattern and menopausal symptoms at regular intervals in order to determine the best dose for that individual.

For women with an intact uterus, combined HRT which includes progesterone is necessary to protect the uterine lining from the effects of unopposed oestrogen (12).

Women who have fibroids are more likely to have an increased risk of challenging bleeding when starting HRT, particularly during perimenopause. Regular review regarding dose and type of progestogen with an expert clinician can help to effectively manage this.

A progesterone-only intrauterine system (IUS) like the Mirena coil is particularly useful as the coil works by releasing a small amount of the hormone levonorgestrel (a type of progestogen) directly into the uterus. This reduces heavy and painful bleeding which is more common in women who have fibroids. The mirena coil also works as contraception which can be helpful for perimenopausal women who have menopausal symptoms and a background of fibroids that is driving heavy and painful periods.

If women have multiple fibroids or submucosal fibroids, insertion of an intrauterine system can sometimes be challenging and require specialist input.

Treatment of fibroids

As you get closer to menopause, your fibroids may shrink and if you do have symptoms, these can resolve on their own. If you are experiencing symptoms that are affecting your quality of life, then there are a range of potential treatment options.

Tranexamic acid

For people suffering from heavy painful periods due to fibroids, tranexamic acid can be used to reduce the bleeding and anti-inflammatory medication, such as mefenamic acid, can help with period pains.

Tranexamic acid works by helping your blood to clot and is taken 3-4 times a day during your period, for up to four days (14).

Contraception

Other options include contraceptive pills (the combined oral contraceptive pill or progestogen-only pill) which can make periods lighter.

The IUS, such as the Mirena 'coil', is another option that can lighten or stop periods; however, in some women with submucous fibroids it may be difficult (and sometimes impossible) to insert (14).

Gonadotrophin-releasing hormone analogue

A type of medication known as a GnRH (gonadotrophin-releasing hormone) analogue can be given to shrink fibroids. This is usually a monthly injection, although tablets have also now become available, and are given for a maximum of six months.

These medications can trigger menopausal symptoms and side effects related to low oestrogen levels such as thinning of the bones and, therefore, are sometimes given alongside 'add back' HRT to reduce the effects of an induced menopause. They can also be used prior to surgery to shrink the fibroids, with the aim of making surgery more straightforward (14).

Surgery

Surgical options include removing the womb (hysterectomy) or individual fibroids.

Hysterectomy tends to be the preferred surgical option in women who do not want any (more) children, and myomectomy (surgical fibroid removal) is reserved for those women wishing to conserve their fertility.

Other options include uterine artery embolisation, which is a less invasive procedure cutting off the blood supply to the fibroid and resulting in it shrinking, and endometrial ablation - a procedure to destroy the lining of the womb (endometrial) lining and reduce bleeding (14).

Managing menopause and fibroid symptoms

Although HRT may increase the size of fibroids, it is still an option for most women who would like to take HRT for perimenopausal, and menopausal, symptoms.

Monitoring of fibroids may be necessary, especially if you have atypical fibroids, but under specialist guidance, it should be possible to find a regime that works well for you and improves your overall health and well-being.

The doctors at Menopause Care have supported many women through menopause while navigating the symptoms of other conditions and we have clinicians specialising in fibroids and menopause. If you’d like to discuss tailored options for the effective management of menopause symptoms and understand how these may influence your fibroids, book a consultation with a menopause doctor.

DisclaimerAt Menopause Care, we ensure that everything you read in our blog is medically reviewed and approved. However, the information provided is not meant to replace professional medical advice, diagnosis, or treatment. It should not be relied upon for specific medical advice.

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