Do Fibroids Affect Periods? Symptoms, Causes, & Treatment

You might assume that the larger your fibroids are, the more they'll disrupt your periods. However, it's actually the location of these growths within your uterus, not their size, that has the greatest impact on your menstrual cycle.

A small fibroid in the wrong spot can cause heavier and longer periods than a much larger one elsewhere. Knowing how fibroids affect your cycle can help you recognise the signs early and decide when it's time to speak to a specialist.

What are fibroids?

Fibroids are benign (non-cancerous) growths that develop in or around your uterus. They are made of muscle and fibrous tissue and can vary in size, number and location. Many women have fibroids without ever realising it, as they often cause no symptoms at all.

They are most common during your reproductive years, as fibroid growth is influenced by oestrogen and progesterone, the hormones that regulate your menstrual cycle. This is also why fibroids often shrink after menopause, when these hormone levels naturally decline.

How can fibroids affect your periods?

Not all fibroids affect your periods, but when they do, it is usually because they change how the lining of your uterus (the endometrium) behaves.

Fibroids can affect your periods in several ways:

• They can enlarge the area of the uterine lining that sheds each month, which may lead to heavier menstrual blood flow

• They may interfere with the muscle contractions of the uterus that help slow menstrual bleeding

• Fibroids growing inside the uterine cavity (known as submucosal fibroids) can directly disrupt the lining

• They may trigger the formation of extra blood vessels around the fibroid, adding to a heavier flow

These changes can occur on their own or together, which is why fibroid-related bleeding can vary from woman to woman, even when their fibroids appear similar on imaging.

What symptoms might you notice?

Fibroid-related period symptoms can range from mild to more disruptive. Some women manage with minor adjustments, while others find their symptoms significantly affect daily life.

You might experience:

• Very heavy bleeding, for example, soaking through a pad or tampon every one to two hours

• Passing large blood clots

• Irregular periods or periods lasting longer than seven days

• Painful periods with severe menstrual cramps

• Spotting between periods

• Fatigue, dizziness or breathlessness, which may be signs of anaemia from ongoing blood loss

These symptoms often develop gradually rather than appearing suddenly, which can make them easy to overlook or quietly adapt to over time. 

Why does fibroid pain often feel worse during your period?

Many women find that fibroid-related pain becomes more noticeable during their period, and this is linked to changes happening in their body at that time.

During menstruation, your hormone levels shift, your uterus contracts more strongly and blood flow to the uterus increases. This can make pressure, cramps, and pelvic pain from your fibroids feel more intense. 

If your periods have become more painful over time, fibroids may be contributing, and it may be helpful to discuss this with your doctor.

Do all fibroids cause period problems?

Many women with fibroids have completely normal periods. Whether symptoms develop depends on several individual factors.

Fibroids are more likely to affect your periods depending on:

• Location:

  • Fibroids growing inside the uterine cavity (submucosal fibroids) are more likely to cause heavier bleeding.

• Size:

  • Large fibroids are more likely to lead to noticeable symptoms.

• Number:

  • Having multiple fibroids may increase the chance of symptoms.

• Your hormone levels:

  • These vary from woman to woman and may influence how fibroid symptoms change over time.

Hormone levels are the most variable factor and the hardest to predict. This is one reason symptoms can fluctuate across your cycle and change over time, even if the fibroids themselves remain the same size.

What are the wider signs of fibroids?

Menstrual cycle changes are often the first sign of fibroids, but they are not the only one.

Fibroids can also cause:

• Feeling of fullness in the pelvic area

• Lower back pain

• Frequent urination or constipation

• Abdominal bloating

• Difficulty getting pregnant

These symptoms can be mistaken for other conditions, which is why fibroids are sometimes only identified after they have gone undetected for a while. The reassuring part is that once they are suspected, fibroids are usually straightforward to confirm with a simple ultrasound scan.

If you are unsure whether your symptoms are related to fibroids, request an appointment with Thomson Medical. Our specialist can assess your condition and arrange appropriate tests if needed.

How are fibroids managed?

There are several ways to manage fibroids. Your doctor will discuss the options that best suit your symptoms, your stage of life and whether you are planning a future pregnancy.

Medication

Medication is usually the first step in managing fibroid symptoms, particularly if your symptoms are manageable but still affecting your daily life. Most medications work by easing symptoms such as heavy bleeding or pain, rather than shrinking the fibroids themselves.

Options may include:

• Anti-inflammatory pain relief, such as ibuprofen, to ease pain and reduce bleeding

• Hormonal contraception, such as the combined pill or progestogen-only pill

• A progestogen-releasing intrauterine device (IUD)

• Tranexamic acid taken during your period to help reduce blood loss

• GnRH agonists or antagonists, which can temporarily shrink fibroids and are often used for a short period before surgery

If one medication does not ease your symptoms enough, your doctor may suggest trying a different option or a combined approach. 

Your doctor will assess which approach is most appropriate based on your symptoms and response to initial treatment.

Minimally invasive procedures

If medication does not bring enough relief, there are procedures that may help reduce fibroids without major surgery while preserving the uterus.

These include:

• Uterine artery embolisation (UAE), which blocks the blood supply to fibroids, causing them to shrink

• MRI-guided focused ultrasound, which uses sound waves to break down fibroid tissue

• Radiofrequency ablation, which uses heat energy to shrink fibroids

Outcomes vary from person to person, and each procedure carries its own benefits and considerations. Fibroids can return after these procedures, particularly in younger women. This is worth considering when comparing them with surgical options.

Surgical options

Surgery may be recommended if fibroids are large, causing significant symptoms, or have not responded to other treatments.

Surgical options include:

• Myomectomy, which removes the fibroids while preserving the uterus, may be suitable if you would like to conceive in the future

• Hysterectomy, which involves removing the uterus entirely

Hysterectomy is the only treatment that removes the possibility of fibroids returning. For women who have experienced repeated recurrences and no longer wish to conceive, it may offer more lasting relief. 

For women who are still planning a family or who prefer to keep the uterus, your doctor will help you explore alternatives that suit your goals.

What happens if fibroids are left untreated?

For some women, fibroids remain small and cause no significant problems over time. For others, symptoms can gradually build up and affect daily life, which is why it helps to keep an eye on how you are feeling.

Possible complications may include:

• Anaemia from persistent heavy blood loss

• Severe fatigue that affects your daily activities

• Worsening pelvic pressure or pain

• Fertility or pregnancy complications, depending on the size and location of the fibroids

Fibroids rarely shrink on their own before menopause. In most cases, symptoms are unlikely to improve without some form of treatment or a significant hormonal change, such as the menopause.

When should you see a doctor?

Fibroid symptoms can develop gradually, which means the shift from your usual pattern can feel slow rather than sudden.

It is worth speaking to your doctor if you notice:

• Your periods are much heavier than they used to be

• You are regularly passing large clots

• Your periods last longer than seven days

• You feel tired, dizzy or breathless around the time of your period

• Pelvic pain is affecting your daily routine

You do not need to wait until symptoms feel severe to seek advice. If something feels different from what is normal for you, it is always okay to check in with your doctor. Seeing your doctor early means fibroids can be identified and supported with the right care before symptoms become more difficult to manage.

If something feels different from your usual menstrual pattern, request an appointment with Thomson Medical. Our specialists can assess your symptoms early and recommend appropriate next steps.

FAQ

Can a fibroid block your period?

Can fibroids cause hormonal mood swings?

Fibroids themselves do not directly cause mood swings. However, related factors such as hormonal fluctuations, heavy menstrual bleeding, anaemia and chronic pain can contribute to fatigue and mood changes.

Do hormones change after fibroid removal?

What treatments are available for uterine fibroids affecting periods?

Treatment options include medications, hormonal therapies, minimally invasive procedures and surgery. The most suitable approach depends on your symptoms, the size and location of your fibroids and your future fertility plans.

When should you worry about fibroids?

It is worth speaking with a doctor if you experience heavy periods leading to anaemia, severe or worsening pain, periods lasting longer than seven days, bleeding between periods, or symptoms that interfere with daily activities.

What does fibroid discharge smell like?

Fibroids typically do not cause foul-smelling vaginal discharge. A strong or unpleasant odour is more likely to indicate an infection or another condition.

The information provided is intended for general guidance only and should not be considered medical advice. For personalised recommendations and tailored advice based on your unique situations, please consult a specialist at Thomson Medical. Request an appointment with Thomson Medical today.