Why is my period so heavy and what can I do about it?

By Sina Hartung, MMSC-BMI, Harvard Medical SchoolReviewed by Eureka Health Medical Group
Published: July 9, 2025Updated: July 9, 2025

Summary

Heavy menstrual bleeding—defined as soaking a pad or tampon every hour for several hours, passing clots over 2 cm, or bleeding longer than seven days—most often comes from uterine fibroids, hormonal imbalance (too much estrogen relative to progesterone), intra-uterine devices, blood-thinning medicines, thyroid disorders, or a bleeding-clotting problem such as von Willebrand disease. Less commonly it can signal pregnancy complications or cancer. Seeing a clinician is key if flow limits daily life or causes fatigue.

Why is my period suddenly so heavy this month?

Heavy flow happens when the lining of the uterus builds up more than usual, sheds incompletely, or when the uterus physically cannot contract to stop bleeding. Temporary triggers include stress, sudden weight change, or a new medication, but persistent heavy periods point to an underlying condition.

  • Uterine fibroids increase surface areaBenign muscle tumors present in 25–30 % of women over 30 enlarge the cavity, so more tissue bleeds each cycle.
  • Estrogen surges thicken the liningAnovulatory cycles in teens, perimenopause, or polycystic ovary syndrome (PCOS) leave progesterone low and allow unchecked estrogen to make a thick endometrium.
  • Copper IUDs can double monthly blood lossStudies show average menstrual volume rises 20–100 mL after insertion but typically improves after six months.
  • Blood-thinners reduce clot formationPrescription anticoagulants for heart or clotting conditions increase menstrual loss by up to 70 %.
  • “Heavy bleeding is often multifactorial; we routinely see two or more causes in the same patient,”notes Sina Hartung, MMSC-BMI, underscoring the need for a thorough work-up.
  • Heavy menstrual bleeding affects 1 in 10 womenRoughly 10 % of women meet clinical criteria for menorrhagia, underscoring how common—but still important to evaluate—heavy flow can be. (HH)
  • Changing protection every 2 hours meets CDC criteria for menorrhagiaThe CDC notes that needing to replace a pad or tampon in under 2 hours or passing clots larger than a quarter signals heavy menstrual bleeding that merits medical review. (MNT)

References

When should heavy bleeding signal an emergency?

Certain patterns suggest rapid blood loss or a serious underlying disease. Acting quickly prevents anemia and detects life-threatening conditions such as ectopic pregnancy.

  • Soaking more than one pad per hour for 2+ hours straightThis level of hemorrhage can drop hemoglobin within hours; head to the ER.
  • Passing clots larger than a golf ballClot size correlates with blood volume; clots over 3 cm often reflect >80 mL loss per day.
  • Light-headedness or a racing heartTachycardia above 100 bpm or dizziness indicates circulatory compromise.
  • Positive pregnancy test plus bleedingCould mean miscarriage or ectopic pregnancy, both emergencies.
  • “If a patient looks pale or short of breath, we transfuse or give IV iron the same day,”adds the team at Eureka Health, emphasizing prompt care for unstable vitals.
  • Bleeding between periods or after menopause warrants immediate evaluationThe Mayo Clinic warns that unexpected vaginal bleeding outside of a normal period can signal serious conditions such as cancer and recommends seeking care right away if it occurs. (Mayo)
  • Low blood pressure and faintness point to hypovolemia from rapid blood lossHealthline notes that significant menstrual hemorrhage can progress to hypovolemia, producing dizziness, fainting, tachycardia, and hypotension that require emergency treatment. (Healthline)

References

What medical conditions most commonly drive chronic heavy periods?

Long-standing menorrhagia often stems from gynecologic and systemic disorders. Identifying the root saves repeated short-term fixes.

  • Submucosal fibroids distort the cavityThese grow inside the uterine lining and account for 40 % of surgical cases for heavy bleeding.
  • Adenomyosis thickens the uterine wallEndometrial glands invade muscle, leading to heavy, painful menses after age 35.
  • Thyroid disease alters hormone balanceHypothyroidism slows clearance of estrogen; 14 % of women with heavy periods have an elevated TSH.
  • Inherited bleeding disorders are under-diagnosedUp to 20 % of adolescent girls with severe menorrhagia have von Willebrand disease but many are never tested.
  • “Do not overlook endometrial hyperplasia or cancer in women over 45 with any cycle change,”warns Sina Hartung, MMSC-BMI. An ultrasound and biopsy rule this out.
  • Hormonal ovulation problems are a leading non-structural causeIrregular or absent ovulation in adolescents, perimenopause, or conditions such as PCOS leaves the endometrium unopposed by progesterone and is flagged by major reviews as a frequent reason for sustained heavy bleeding. (Harvard)
  • Menorrhagia impacts roughly 1 in 10 womenHarvard Health notes that about 10 % of women experience heavy menstrual periods, emphasizing the importance of searching for an underlying diagnosis rather than normalizing the symptom. (Harvard)

References

How can I reduce heavy bleeding at home until I see a clinician?

Short-term measures may lessen flow and protect iron stores, but they do not replace a formal evaluation if bleeding is severe or persistent.

  • Track actual pad counts and clot sizeA menstrual diary helps doctors quantify loss; phone apps simplify daily logging.
  • Use NSAIDs at the start of bleedingIbuprofen 600 mg every 6 h can cut prostaglandins and reduce flow by up to 30 %; confirm safe use with your clinician first.
  • Increase iron-rich foods and pair with vitamin CRed meat, lentils, and spinach plus citrus boost ferritin, preventing fatigue from iron deficiency.
  • Ensure adequate hydration and electrolytesLost blood volume pulls fluid from tissues; oral rehydration solutions maintain perfusion.
  • “A heating pad lowers cramping, which in turn reduces secondary blood loss from uterine spasms,”suggests the team at Eureka Health as an easy, non-drug step.
  • Choose acetaminophen over aspirin for painBecause aspirin keeps platelets from clotting, it can make menstrual bleeding heavier; opt for paracetamol (or ibuprofen if tolerated) instead until you can be examined. (Healthline)
  • A menstrual cup reduces product changes and helps gauge volumeSilicone cups hold considerably more fluid than tampons or pads, so you can empty them every 6–12 hours and even track the millilitres lost while awaiting professional care. (MNT)

References

Which tests and treatments clarify and control heavy menstrual bleeding?

Your clinician will tailor investigations to age and symptoms, often starting with labs and imaging before prescribing hormonal or surgical options.

  • Complete blood count and ferritin gauge impactA hemoglobin below 10 g/dL or ferritin under 30 ng/mL confirms iron deficiency.
  • TSH and coagulation profile find hidden contributorsOne abnormal lab explains heavy bleeding in 15 % of cases.
  • Pelvic ultrasound maps fibroids and lining thicknessEndometrial stripe over 12 mm in premenopausal women suggests hyperplasia.
  • Hormonal therapies thin the liningCombined oral contraceptives, oral progesterone, or the levonorgestrel IUS can reduce menstrual volume by 70–90 % within three cycles—your prescriber will decide what’s safe.
  • “When medical therapy fails, hysteroscopic resection or endometrial ablation offers 80 % satisfaction rates,”reports Sina Hartung, MMSC-BMI, noting that childbearing plans guide surgical choices.
  • Large clots and rapid “flooding” point to inherited bleeding disordersPassing clots at least 1 inch wide or soaking through protection in under an hour occurs in up to 90 % of women ultimately diagnosed with a coagulation defect, so clinicians add von Willebrand and platelet studies early in the work-up. (PMC)
  • Office endometrial biopsy quickly rules out cancer when imaging is unclearMayo Clinic lists biopsy among first-line tests whenever ultrasound is inconclusive or risk factors are present, allowing same-day sampling of the uterine lining for hyperplasia or malignancy before selecting therapy. (MayoClinic)

References

How Eureka Health’s AI doctor guides you through heavy period evaluation safely

The AI doctor inside the Eureka app uses your symptom timeline to suggest next steps and flags red-alert patterns that need urgent care. Licensed physicians review every clinical recommendation before anything is ordered.

  • Dynamic symptom triage within secondsEntering pad counts and clot descriptions prompts the AI to advise ER, same-day clinic, or home measures.
  • Lab and imaging suggestions reviewed by doctorsIf thyroid tests or an ultrasound are appropriate, the AI drafts the order and a physician signs off.
  • Medication pathways with safety checksAlgorithm weighs anemia, contraceptive needs, and clot risk before proposing hormonal options.
  • Continuous learning from anonymized outcomesAccuracy improves as more women log their cycles, maintaining >92 % agreement with gynecologist recommendations.
  • “Users say the app explains findings better than a 10-minute office visit,”shares the team at Eureka Health, highlighting the educational value.

Women are using Eureka to track cycles, order labs, and feel heard—could it help you?

Eureka’s private, HIPAA-compliant platform lets you log flow, receive tailored advice, and request clinician-approved care—all at no cost.

  • Cycle tracking integrates with wearablesHeart-rate variability and sleep data refine hormone predictions.
  • Instant access to prior lab resultsGraphs show hemoglobin trends so you can see if treatments work.
  • Optional reminders for iron or hormonal pillsAdherence nudges cut missed doses by 35 % in beta testing.
  • High satisfaction among heavy-bleeding usersWomen using Eureka for menstrual issues rate the app 4.8 out of 5 stars.
  • “I finally understood why my periods were heavy and got the right ultrasound within a week,”reports a verified user, quoted by the team at Eureka Health.

Become your own doctor

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Frequently Asked Questions

Is it normal to pass clots during my period?

Small clots under 2 cm can be normal, but larger clots or many clots suggest heavy bleeding that needs evaluation.

How much blood loss counts as ‘heavy’?

More than 80 mL per cycle, roughly the amount that soaks through a regular pad every 3 hours or requires double protection, is defined as heavy.

Do hormonal IUDs stop heavy periods?

The levonorgestrel IUD reduces menstrual flow by up to 90 % after six months and often leads to very light or absent periods.

Can I still be anemic if my iron blood test is normal?

Yes—your hemoglobin may be normal while ferritin (iron stores) is low; ask for both tests.

Will losing weight help my heavy bleeding?

Even a 5–10 % weight loss lowers estrogen made in fat tissue and can lighten periods in women with PCOS.

Should teenagers with heavy periods see a hematologist?

If screening labs suggest a bleeding disorder or there is a family history, referral to a hematologist is recommended.

Can stress alone cause heavy periods?

Severe stress can disrupt ovulation, leading to hormonal imbalance and heavier bleeding, but clinicians still look for additional causes.

How long should I try NSAIDs before looking for other treatments?

If flow does not improve within two cycles of properly timed NSAID use, seek a full evaluation.

Is endometrial ablation safe if I want children later?

No; ablation destroys the lining and is only for women who are done with childbearing.

Could I have heavy bleeding during peri-menopause?

Yes, fluctuating hormones often cause irregular, heavier cycles between ages 40–55; a pelvic ultrasound rules out structural causes.

This content is for informational purposes only and is not intended as medical advice. Always consult with a qualified healthcare provider for diagnosis, treatment, and personalized medical recommendations.

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