Fibroids Heavy Periods: Why Your Flow Is So Heavy and How to Treat It

Heavy, long or painful periods; large clots or suddenly heavier bleeding; spotting between cycles and wondering what it means.

Quick answer: Fibroids are benign muscle growths in the uterus that commonly cause heavy, prolonged, or painful periods by increasing the uterine surface area, altering blood flow, and changing contractility. Common treatments include tranexamic acid for bleeding control, hormonal methods like the levonorgestrel IUD, and procedures from myomectomy to uterine artery embolization depending on size, symptoms and desire for future pregnancy.

Get it checked if bleeding causes fainting, very heavy soaking, or severe pain, or if you are trying to conceive and suspect fibroids could interfere.

What are uterine fibroids and who gets them

Fibroids, also called leiomyomas or myomas, are benign tumours that grow from the smooth muscle of the uterus. They are not cancer. Most fibroids are multiple, vary in size from pea sized to grapefruit sized, and often shrink after menopause when estrogen levels fall.

Fibroids are very common. By age 50, most people with a uterus will have at least one fibroid on imaging, but not everyone has symptoms. Black people and those assigned female at birth with a family history tend to develop fibroids earlier and more severely. Other risk factors include obesity and early first period, while pregnancy seems to reduce long-term fibroid risk.

Why some fibroids cause heavy bleeding and others do not is partly about location and partly about how they change uterine function. A fibroid on the inside of the uterine cavity, for example, often causes more bleeding than one embedded in the wall. Growth is hormonally sensitive, which is why symptoms often appear or worsen in the reproductive years.

Who this guide is for: people with heavy or long periods, new clots, or bleeding between periods; those deciding whether to get imaging; and people weighing medical versus procedural treatments.

How fibroids cause heavy periods and clots

Fibroids increase bleeding in several overlapping ways.

Increased surface area: Submucosal fibroids that bulge into the uterine cavity expand the endometrial surface that sheds each cycle. More surface means more bleeding.

Impaired contraction: The uterus normally contracts after ovulation and during menstruation to compress blood vessels. Fibroids can disrupt normal muscle contraction, so bleeding is less controlled.

Abnormal blood supply: Fibroids recruit blood vessels and can cause weaker or more fragile vessel walls, leading to heavier flow and larger clots.

Inflammation and endometrial changes: Fibroids affect the lining’s ability to form a stable clot at the end of an interval and may increase local inflammation, which delays the normal blood-clotting cascade.

What to expect on periods with fibroids: heavier flow than usual, bleeding that lasts longer than seven days, passing clots larger than a quarter, and sometimes bleeding between periods. Pain is common when fibroids cause pressure, distort the uterine cavity, or trigger strong contractions.

Research strength: Multiple observational studies and clinical trials support these mechanisms and the effectiveness of treatments that reduce uterine volume or suppress bleeding. Randomized trials support the levonorgestrel intrauterine device for reducing heavy menstrual bleeding, and trials support tranexamic acid for symptomatic control of heavy menses unrelated to fibroids as well, with growing evidence for fibroid-related bleeding.

Typical symptoms: uterine fibroids symptoms to watch for

Not all fibroids cause symptoms, but when they do, the pattern is often consistent.

Bleeding symptoms: Heavy menstrual bleeding, prolonged periods, clots, and spotting between periods. If bleeding causes fatigue or iron deficiency, that is a key red flag.

Pain and pressure: Cramping that is worse than your usual period pain, pelvic pressure, or a feeling of fullness. Large fibroids press on the bladder causing frequency, or on the bowel causing constipation.

Reproductive symptoms: Difficulty conceiving, recurrent miscarriage, or pregnancy complications can occur with certain fibroid types, especially those that distort the uterine cavity.

When symptoms are subtle: Some people have only bloating or a sense of pelvic heaviness. Because fibroid size does not always match symptoms, clinical judgement and imaging matter.

If you are noticing a clear change in bleeding pattern or new pressure symptoms, log them and discuss imaging with your provider. Our guide to how the menstrual cycle works explains the normal baselines that help spot changes.

Fibroids and clots: why clots happen and when they are dangerous

Passing clots during menstruation is common, especially with heavy flow. Clots form when blood pools in the uterus and partially coagulates before being expelled.

Why fibroids increase clots: Heavy continuous bleeding combined with impaired uterine contractility increases pooling. Submucosal fibroids that alter the cavity geometry trap blood more easily.

When clots are a concern: Occasional small clots are not dangerous. Seek care if you pass very large clots frequently, if clots are associated with fainting or dizziness, or if bleeding soaks through a pad or tampon in an hour for several hours. Those are signs of heavy blood loss and possible anemia.

Managing clots at home: Rest and use pain control like ibuprofen if you can take it, because nonsteroidal anti-inflammatory drugs reduce menstrual bleeding by blocking prostaglandins and can help clotting indirectly. If you have kidney disease, stomach ulcers or are on blood thinners, talk to your clinician before using NSAIDs. Consider using period underwear or high-absorbency protection; our review of the best period products for heavy flow can help pick options.

How fibroids are diagnosed: what ultrasound shows and why type matters

Pelvic ultrasound, usually transvaginal ultrasound, is the first-line test to find fibroids. It is fast, available and shows size, number and approximate location. A transabdominal scan may be used for very large fibroids.

How radiologists describe fibroids:

• Submucosal: under the lining and bulging into the cavity, most likely to cause heavy bleeding and fertility issues.
• Intramural: within the uterine wall, the most common type and variably symptomatic.
• Subserosal: on the outer surface, more likely to cause pressure than heavy bleeding.

Ultrasound can miss very small submucosal fibroids or underestimate number when many are present. If the cavity needs clearer detail, saline infusion sonography or pelvic MRI gives better mapping, which matters for surgical planning.

What your provider will measure: number, largest diameter, exact location, and whether the fibroid distorts the uterine cavity. They will also check for other causes of heavy bleeding, such as polyps or adenomyosis, which can coexist. If you have irregular bleeding or pain that is out of proportion to fibroid size, your clinician may recommend further tests, such as hemoglobin to check for anemia or endometrial sampling in those over typical risk ages for endometrial pathology.

Medical treatments that reduce bleeding: what works and what to expect

Medical options aim to reduce bleeding, shrink fibroids, or both. Choice depends on symptom severity, desire for pregnancy, and medical history.

Tranexamic acid: An antifibrinolytic that helps blood clot more efficiently during heavy bleeding. For menstrual use, it is taken during days of heavy bleeding. It reduces blood loss by about 30 to 50 percent in trials of heavy menstrual bleeding and can help if fibroids are the cause. It is non-hormonal, so it is a good option for people who cannot or prefer not to use hormones. It should not be used if you have a history of blood clots or on certain medications without medical advice. See our deep dive on tranexamic acid for heavy periods.

Nonsteroidal anti-inflammatory drugs (NSAIDs): Drugs like ibuprofen reduce prostaglandin-related bleeding and cramps, lowering blood loss by roughly 20 to 40 percent. They may not be sufficient alone for very heavy fibroid bleeding.

Combined hormonal methods: Combined oral contraceptives, the patch and the ring can reduce bleeding and regulate cycles. They are useful if contraception is also a goal. People with migraine with aura, certain clotting disorders or older age may not be candidates for estrogen-containing methods.

Progestin-only options, especially the levonorgestrel IUD: The levonorgestrel intrauterine device (Mirena and similar) often reduces menstrual bleeding by 70 to 90 percent and is one of the most effective medical options for controlling fibroid-related bleeding when the cavity is not severely distorted. It also causes local thinning of the endometrium and may reduce anemia. If you have a distorted cavity from submucosal fibroids, insertion may be more difficult or less effective; discuss imaging results with your clinician and consider our comparison of hormonal IUD vs the pill.

Gonadotropin-releasing hormone (GnRH) agonists or antagonists: These drugs induce a temporary menopause-like state to shrink fibroids and reduce bleeding quickly, but they cause menopausal symptoms and bone loss if used long term. They are often used as a short-term bridge before surgery or to improve anemia before a procedure.

Who should not use which medical option: People with a history of venous thromboembolism should avoid combined hormonal methods and often avoid tranexamic acid. Those with liver disease or severe migraine need tailored counselling. If mood changes are a concern, note that some people experience mood side effects on hormonal treatments; monitor and discuss with the prescriber.

Procedural and surgical options: when to consider them and how they compare

When bleeding is severe, medical therapy fails, or fertility goals require removal, procedures are the next step.

Hysteroscopic myomectomy: A minimally invasive surgery to remove submucosal fibroids protruding into the uterine cavity. It preserves the uterus and often resolves heavy bleeding caused by cavity-distorting fibroids.

Laparoscopic or open myomectomy: For larger intramural or subserosal fibroids, myomectomy removes fibroids and preserves fertility, but recovery varies with approach and number of fibroids.

Uterine artery embolization (UAE): A radiological procedure that blocks blood flow to fibroids, causing them to shrink. It is uterus sparing but may affect ovarian reserve in some people and is not recommended if future pregnancy is a priority for some patients.

Magnetic resonance-guided focused ultrasound: A noninvasive option for selected fibroids causing symptoms. Access and eligibility vary.

Hysterectomy: Definitive surgery that removes the uterus and resolves fibroid bleeding permanently. It is appropriate for people who no longer want pregnancy and have not benefited from other treatments or have very large or numerous fibroids.

Table: comparison of common fibroid treatments

Choosing a procedure depends on fibroid type, symptom severity, age, and reproductive plans. Discuss the risks, benefits and recovery expectations with your gynecologist or a specialist at a women's health clinic.

How treatment decisions are made: factors your clinician will consider

Clinicians balance symptoms, imaging, fertility goals and medical risks when recommending treatment.

Symptom severity: How much bleeding, impact on daily life, and whether you have iron deficiency anemia matter.

Fibroid mapping: Location and number on ultrasound or MRI determine whether a hysteroscopic approach can remove submucosal fibroids or whether myomectomy is needed.

Desire for future pregnancy: For those who want pregnancy, myomectomy is commonly preferred over UAE or hysterectomy, but each case is individual.

Medical risks and preferences: Blood clotting history, smoking, age and tolerance of hormonal therapy influence whether combined hormones, tranexamic acid, or devices like the levonorgestrel IUD are recommended.

Access and cost: Not every option is available everywhere. Interventional radiology or MR-guided treatments may be limited to specialized centres.

Your clinician should explain expected outcomes in concrete terms, for example the percent reduction in blood loss you might expect from a levonorgestrel IUD versus a myomectomy, and the likely recovery timeline.

Lifestyle, iron and symptom control while you decide

While you decide on imaging or definitive treatment, you can reduce harm and feel better with practical steps.

Iron and nutrition: Heavy bleeding commonly causes iron deficiency. Get a hemoglobin and ferritin test and treat low iron with oral iron or intravenous iron if severe. Dietary iron is helpful but often insufficient alone when losses are large.

Pain control: For cramps use ibuprofen or naproxen if you can take them; they reduce both pain and bleeding. Heat and rest help. Our guides on ibuprofen for cramps and heating pad for cramps explain safe use.

Tracking bleeding: Use Periodwise Track at /track or a paper log to record number of pads/tampons soaked per hour and when clots occur. That data helps clinicians quantify blood loss and decide on treatment.

Practical supports: Choose high-absorbency protection; our list of best period products for heavy flow helps. If bleeding is unpredictable, carry spare clothing and emergency supplies.

When to see a doctor about fibroids and heavy bleeding

If you have concerning bleeding or related symptoms, this is when to get care.

See a doctor if you have any of the emergency signs below, same-day is needed for the first list:

• Passing large clots with dizziness, fainting, or vomiting
• Bleeding that soaks a pad or tampon every hour for several hours
• Severe, unrelieved pelvic pain with fever
• Heavy bleeding during pregnancy or suspected pregnancy
• Signs of severe anemia such as chest pain or shortness of breath

Book a routine appointment if you have:

• Heavy or prolonged periods that interfere with daily life but are not life threatening
• New pelvic pressure, bloating, or urinary frequency
• Concern about fertility and known or suspected fibroids
• Symptoms of iron deficiency like fatigue or hair loss

If you are unsure which route to take, our when to seek care guide explains emergency versus routine signs, and you can chat with Sarah, the Periodwise assistant for quick next-step suggestions.

Questions to ask your clinician and how to prepare for an appointment

Bring a simple bleeding log and your medical history. Useful questions include:

• What type and size of fibroid do I have, and does it explain my bleeding?
• Will medical treatment likely control my bleeding, or do I need a procedure?
• What are the chances of needing future surgery after trying medical options?
• If I want pregnancy, which treatments preserve fertility best?
• What iron tests and treatments do you recommend now?

Ask for imaging reports in plain language and request exact measurements and whether the cavity is distorted. If a procedure is recommended, ask about alternatives, risks and recovery time, and whether you will need blood tests or optimization of iron first.

Frequently asked questions

What is the difference between fibroids and adenomyosis for heavy periods

Fibroids are discrete muscle growths in the uterus, while adenomyosis is when endometrial tissue grows into the uterine muscle. Both can cause heavy or painful periods, but adenomyosis often causes a uniformly enlarged, tender uterus and more diffuse pain. Imaging and clinical exam help distinguish them; they can also occur together.

Can a single fibroid cause very heavy bleeding or do they have to be multiple

Yes, a single fibroid can cause heavy bleeding, especially if it is submucosal and bulges into the uterine cavity. Location often matters more than number. Even small submucosal fibroids can cause disproportionate bleeding.

Will the levonorgestrel IUD help if I have fibroids

The levonorgestrel IUD often reduces bleeding dramatically, and many people with fibroids find their periods much lighter or stop bleeding. If fibroids severely distort the uterine cavity, insertion may be harder and effectiveness may be reduced, so discuss your ultrasound findings with the provider. See more in our hormonal IUD overview.

Is tranexamic acid safe for fibroid-related bleeding

Tranexamic acid is effective for reducing heavy menstrual blood loss and can help with fibroid-related bleeding for many people. It is a non-hormonal option. Avoid it or use cautiously if you have a history of blood clots or certain clotting disorders; check with your clinician before starting it.

Do fibroids increase the risk of cancer

Fibroids are benign and do not become cancer in the vast majority of cases. Uterine sarcoma is rare. Rapidly growing fibroids in perimenopausal or postmenopausal people warrant investigation, but most growth is benign and hormone driven.

Can fibroids cause bleeding between periods

Yes, fibroids can cause spotting or bleeding between periods, particularly if they are submucosal or ulcerate the endometrial surface. However, other causes such as polyps, infection, or hormonal fluctuations are also possible, so evaluation is helpful.

If I want to get pregnant, do fibroids always need to be removed

Not always. Small intramural or subserosal fibroids often do not affect fertility. Submucosal fibroids that distort the uterine cavity are more likely to cause infertility or miscarriage and are commonly removed. Discuss fertility goals with your gynecologist and consider imaging to guide decisions.

How quickly will bleeding improve after a treatment like UAE or myomectomy

Many people notice reduced bleeding within one to three menstrual cycles after uterine artery embolization. After myomectomy, bleeding often improves once the uterine lining heals, typically within one to three months, but timelines vary with the procedure and individual healing.

Can lifestyle changes make a big difference in fibroid bleeding

Lifestyle changes like maintaining a healthy weight and stopping smoking may reduce fibroid growth risk over time, and treating iron deficiency improves symptoms of fatigue. However, lifestyle measures alone rarely stop heavy bleeding caused by fibroids, so medical evaluation is usually needed.

When should I consider a hysterectomy for fibroids

Hysterectomy is an appropriate option when symptoms are severe, other treatments have failed or are not desired, and future pregnancy is not wanted. It is definitive for bleeding and pressure symptoms. Discuss recovery, alternatives, and long-term effects with your clinician before deciding.

Where can I get more help and what resources are useful

Start with a primary care clinician or a gynecologist for evaluation and imaging. Planned Parenthood clinics and sexual health clinics can provide initial assessment and contraception options. For second opinions about procedures, ask for referral to a reproductive surgeon or interventional radiology. Use our topics on conditions page to learn more and reach out to Sarah, the Periodwise assistant for quick questions.