Ferritin: 9. That was the number on the lab report she slid across my desk, and the reference range printed beside it started at 12. Her doctor had called it “normal” anyway, because her hemoglobin sat just inside the range.
She is 47. She has soaked through a pad every 90 minutes on day two of her period for the past year. And she has been so tired that she now sits down to put on her socks. In fact, nobody had tied her exhaustion to her bleeding, because the visit notes said “perimenopause, expected” and nothing else. That is conventional medicine’s answer, and I have never been satisfied with it.
Perimenopause heavy bleeding is common, but common does not mean harmless, and it does not mean you should wait it out. Some of it comes from hormone swings. Some comes from fibroids, polyps, or thyroid problems. And a small slice needs a biopsy. So let’s sort out what is typical, what is a red flag, which tests I order, and what treatments work.
How Common Is Perimenopause Heavy Bleeding?
In fact, it is very common. A 2025 study in the journal Menopause followed more than 2,300 midlife women from the Study of Women’s Health Across the Nation (SWAN). Specifically, the women kept daily menstrual calendars for up to 10 years. About 1 in 3 had episodes of abnormal uterine bleeding as they moved through the menopause transition.
Here’s what they found about energy. Women with three or more heavy bleeding episodes in a 6 month window had 62% higher odds of feeling tired and 44% higher odds of feeling worn out. Women with three or more prolonged episodes had 32% lower odds of feeling full of pep. The results held after the researchers adjusted for sleep problems.
Translation: your fatigue is not “just stress.” The bleeding itself may be draining you. In addition, the study did not measure blood iron, so the authors could not prove that iron loss explains the link. They did suggest it as a likely cause, and they advised doctors to ask about bleeding and to test for low iron and anemia when women report fatigue. I agree with every word of that advice.
What Is Normal in Perimenopause, and What Is Not
Perimenopause is not a steady slide. Instead, your cycles can get shorter, then longer, then skip a month, then come back with a vengeance. That is normal. Because ovulation becomes erratic, progesterone drops while estrogen stays high or spikes. As a result, the uterine lining builds up thicker than usual, and then it sheds all at once.
That said, there are limits. The American Academy of Family Physicians review of abnormal uterine bleeding uses these benchmarks:
- Normal blood loss: 5 to 80 mL per cycle.
- Heavy menstrual bleeding: more than 80 mL per cycle.
- Normal period length: 4.5 to 8 days.
- Prolonged bleeding: more than 8 days.
- Normal cycle spacing: 24 to 38 days apart.
Nobody measures 80 mL at home. So the Mayo Clinic gives practical signs. Heavy bleeding means soaking through one or more pads or tampons every hour for several hours in a row. On top of that, heavy bleeding means passing clots larger than a quarter, or bleeding for more than a week. Additionally, Mayo says to seek help right away if you soak at least one pad or tampon an hour for more than two hours in a row, or if you bleed between periods. You can read the full list on Mayo Clinic’s heavy periods page.
Red Flags That Need Prompt Attention
No doctor should file these patterns under “just perimenopause.” Call your doctor if you notice any of these:
- Bleeding after sex or between periods.
- Bleeding that returns after 12 months without a period. That is bleeding after menopause, and it always needs a workup.
- Periods closer than 21 days apart for several months in a row.
- Dizziness, a racing heart, or shortness of breath on the stairs.
- Soaking a pad or tampon every hour for 2 hours or more.
- Heavy bleeding that began suddenly and looks nothing like your old pattern.
Why Perimenopause Heavy Bleeding Happens
Doctors use a memory aid called PALM-COEIN to sort the causes. The first four letters are structural: polyps, adenomyosis, leiomyoma (fibroids), and malignancy or hyperplasia. The last five are not structural: coagulopathy (a clotting problem), ovulation problems, the endometrium itself, medicine side effects, and causes not otherwise classified.
In my practice, five causes show up again and again:
- Anovulatory cycles. When you skip ovulation, you make no progesterone. Estrogen keeps building the lining with nothing to settle it down.
- Fibroids. These muscle growths are common in the 40s and can make periods heavy and long.
- Polyps. These soft growths on the lining cause spotting and heavy flow.
- Adenomyosis. Here the lining grows into the uterine wall, which causes heavy, painful periods.
- Thyroid disease. Both underactive and overactive thyroid change your cycle.
Because this list is long, guessing does not work. As a result, I do not assume hormones are the culprit until the workup says so.
The Workup I Order for Perimenopause Heavy Bleeding
In contrast to the months many women wait, a good evaluation takes a few labs and one imaging study. According to the AAFP review, every woman with abnormal bleeding needs a pregnancy test and a complete blood count (CBC), which checks for anemia and low platelets. Thyroid testing follows when symptoms suggest it or when the first round shows nothing.
Here’s my list, and it goes a step further than the standard one:
- Pregnancy test. Perimenopause does not rule out pregnancy.
- CBC. It shows hemoglobin and platelets.
- Ferritin. This measures your iron stores, which drop long before hemoglobin does.
- TSH, plus free T4 if needed. Thyroid problems mimic and worsen heavy bleeding.
- Clotting screen when history suggests it. For example, I ask about heavy periods since your teens, nosebleeds, easy bruising, or bleeding after dental work.
- Transvaginal ultrasound. The AAFP calls this the first-line imaging test. It finds fibroids, polyps, and a thick lining.
Why Ferritin Matters More Than Hemoglobin
Many women walk out with a “normal” CBC and a fatigue they cannot explain. Here’s why: hemoglobin falls late, and ferritin falls first. In 2026, the American Society of Hematology published new guidelines in Blood Advances that raised the cutoff. For women who menstruate, a ferritin of 30 ng/mL or lower suggests iron deficiency. In addition, for women with heavy or abnormal uterine bleeding, symptoms, or risk factors, the suggested cutoff is 50 ng/mL or lower. In other words, the older lab cutoff of 15 or so missed many women. According to a news summary of the ASH guideline, these thresholds guide your doctor’s judgment and are not automatic triggers for iron pills.
So the woman in my opening, with a ferritin of 9, did not have “normal” labs. She had empty iron stores, and she had been bleeding into them for a year.
Do You Need an Endometrial Biopsy?
Sometimes, yes. The AAFP says to sample the lining in every woman with abnormal bleeding who is 45 or older. Younger women need it if they have long exposure to unopposed estrogen, if bleeding persists, or if treatment fails. Long-term unopposed estrogen raises endometrial cancer risk by a relative 10 to 20 times in the AAFP’s summary.
That sounds scary, so here is the plain version. Specifically, a biopsy takes a few minutes in the office. Most results are benign. That said, a thickened lining or a bleeding pattern that does not respond to treatment deserves tissue, not guesswork.
Perimenopause Heavy Bleeding Treatment: What Works
Treatment depends on the cause, on whether you want to keep bleeding at all, and on whether you want contraception. The AAFP lists the following medical options, with reductions in blood loss:
- Levonorgestrel IUD (Mirena, 20 mcg per day): 71% to 95% less blood loss. It is the most effective medical option.
- Continuous oral progestins: 87% less blood loss, though long-term satisfaction is low.
- Combined birth control pills: 35% to 69% less blood loss.
- Tranexamic acid (Lysteda): 26% to 54% less blood loss. The AAFP lists 1,000 to 1,500 mg three times daily during bleeding days.
- NSAIDs such as naproxen, 500 mg twice daily: 10% to 52% less blood loss.
In addition, endometrial ablation and hysterectomy remain options for women who finish with medicines. The AAFP calls hysterectomy definitive and ablation as effective as the levonorgestrel IUD.
The Levonorgestrel IUD
In my experience, this is the best first choice for many women in their 40s. Because it thins the lining, it cuts bleeding by up to 95% in the AAFP’s figures, and also provides contraception. Spotting is common for the first 3 to 6 months. However, it is a local treatment, so it does not fix hot flashes or sleep.
Tranexamic Acid
Tranexamic acid helps blood clots hold on. Instead of a daily pill, you take it only on heavy days, and it contains no hormones. In other words, it suits women who cannot use hormones or want a short, targeted tool. However, women with a history of blood clots, stroke, or certain clotting disorders should not take it without a careful review.
Progesterone
So when anovulation drives the bleeding, the missing piece is progesterone. Many doctors, myself included, prescribe cyclic micronized progesterone for about 12 days a month to give the lining a regular, orderly shed. This is a common practice approach, and it also helps sleep and mood for many women. For the full story on this hormone, see my post on micronized progesterone in perimenopause. However, if bleeding stays heavy or irregular on progesterone, we go back to imaging and biopsy instead of just raising the dose.
Iron: Treat the Cause and the Result
Stopping the bleeding is only half the job. Additionally, your stores need rebuilding. If your ferritin sits at or below the guideline cutoff, I treat it, even when your hemoglobin looks fine. Options include oral iron every other day, which many women tolerate better than daily dosing, and iron through an IV when oral iron fails or when the deficit is large. We recheck ferritin in about 8 to 12 weeks, and I want to see it rise.
What This Looks Like in Practice
A patient I’ll call Diane came to me at 48. She had two heavy periods a month, clots the size of a plum, and a ferritin of 11. She had been told to “wait it out until menopause.” This story is an illustrative composite, but I see this pattern every month.
First, we ran a CBC, ferritin, and TSH, then ordered a transvaginal ultrasound. It showed a small fibroid and a normal lining, and her biopsy came back benign. Because she wanted contraception too, she chose a levonorgestrel IUD. Then we started iron every other day. Within 4 months her periods had shrunk to light spotting. Her ferritin reached 58, and she told me she could finally finish a workday without a nap.
What Not to Do While You Wait for Answers
A few mistakes come up often, and each one is easy to avoid.
- Skip the aspirin. Aspirin thins your blood and can make flow heavier. Naproxen or ibuprofen is the safer pain pick, and the AAFP lists naproxen as a treatment that cuts blood loss by 10% to 52%.
- Test before you start iron. Iron without a ferritin test can hide the real problem, and too much iron causes constipation and stomach upset. Test first, then treat.
- Keep a pattern log. For 2 to 3 cycles, jot down the start date, the number of pads or tampons per day, and any clots. As a result, your doctor sees the pattern in 30 seconds.
- Reject “it’s your age” as a diagnosis. Age explains the hormone swings. It does not explain a fibroid, a polyp, or a ferritin of 9.
In addition, bring a list of every medicine and supplement you take. Blood thinners, some antidepressants, and certain herbal products raise bleeding risk. So a short medication review sometimes solves part of the puzzle before we touch a hormone.
Perimenopause Heavy Bleeding and Your Daily Life
The numbers matter, but the lived experience matters just as much. Here is what women in my practice describe.
In fact, heavy bleeding steals more than iron. Women tell me they skip workouts, cancel trips, carry spare clothes, and plan their week around a toilet. In addition, the bleeding often arrives during the same years when sleep, mood, and weight are shifting. So fatigue stacks on fatigue.
So I treat the whole picture at Living Well Dallas Functional Medicine Center. Specifically, we check iron, thyroid, blood sugar, stress, sleep, and hormones together, because each one shapes the others. For example, an underactive thyroid can worsen bleeding, and heavy bleeding can worsen the fatigue that people blame on the thyroid. In a 10 minute visit, nobody connects those dots.
Key Takeaways
- About 1 in 3 women in the SWAN study had abnormal uterine bleeding during the menopause transition, and heavy bleeding raised the odds of feeling tired by 62%.
- Heavy bleeding means more than 80 mL per cycle, a pad or tampon soaked every hour for several hours, clots bigger than a quarter, or bleeding past 8 days.
- Ask for a CBC, ferritin, TSH, and a transvaginal ultrasound; women 45 and older with abnormal bleeding need endometrial sampling per the AAFP.
- A levonorgestrel IUD cuts blood loss by 71% to 95%, tranexamic acid by 26% to 54%, and combined pills by 35% to 69%.
- A ferritin of 50 ng/mL or lower in a woman with heavy bleeding suggests iron deficiency under the 2026 ASH guideline, even when hemoglobin looks normal.
Frequently Asked Questions
How heavy is too heavy during perimenopause? Soaking a pad or tampon every hour for more than 2 hours in a row, passing clots larger than a quarter, or bleeding past 8 days is too much. So call your doctor if any of those sound familiar. Additionally, any bleeding between periods needs a visit.
Can perimenopause heavy bleeding cause anemia and fatigue? Yes. Because iron leaves your body with every heavy period, and low iron causes exhaustion, hair shedding, and shortness of breath. In fact, the 2025 SWAN analysis tied heavy bleeding to 62% higher odds of feeling tired. So ask for a ferritin, not just a CBC.
Tests and Red Flags
Which tests should I ask for? Ask for a pregnancy test, CBC, ferritin, TSH, and a transvaginal ultrasound. Specifically, add a clotting screen if you have bled heavily since your teens. If you are 45 or older, ask whether you need an endometrial biopsy.
When is heavy bleeding a sign of cancer? Most cases are not cancer. That said, bleeding after 12 months without a period, bleeding between periods, or a thick lining on ultrasound needs tissue testing. As a result, do not ignore a change in your pattern.
Treatment Choices
What is the best treatment for perimenopause heavy bleeding? It depends on your cause and your goals. Specifically, the levonorgestrel IUD cuts blood loss the most, at 71% to 95%. Tranexamic acid works without hormones, and cyclic progesterone helps when you skip ovulation. So we pick by cause, not by habit.
Will my periods just stop on their own? Eventually, yes, but perimenopause can last several years. In contrast, iron loss and fatigue happen now. So treat the bleeding and the low iron while you wait for menopause to arrive.
Dr. Betty’s Bottom Line
I’ve watched too many women told to wait it out while their ferritin sank into the single digits. Heavy periods in your 40s are common. In fact, they are also treatable, and they are worth testing.
So ask for a ferritin and a thyroid test. Ask for an ultrasound. And if you are 45 or older, ask whether a biopsy makes sense. Then choose a treatment that matches your goals, whether that means an IUD, tranexamic acid, or progesterone, and rebuild your iron on top of it.
Because you deserve a plan built on your numbers, not a shrug. Perimenopause is a transition, and it is not a reason to bleed through your clothes and your energy.
In-person care at Living Well Dallas Functional Medicine Center is available for patients in the Dallas area, including a full workup with ferritin, thyroid, and other labs, ultrasound coordination, and a personalized plan for heavy or irregular bleeding.
Source: Abnormal uterine bleeding is associated with fatigue during the menopause transition. Menopause. Online March 12, 2025 (SWAN; Harlow et al.). Summary via The Menopause Society press release: https://menopause.org/wp-content/uploads/press-release/Abnormal-bleeding-and-fatigue.pdf Also: Abnormal Uterine Bleeding in Premenopausal Women. Am Fam Physician. 2019;99(7):435-443. https://www.aafp.org/pubs/afp/issues/2019/0401/p435.html; Mayo Clinic, Heavy menstrual bleeding: https://www.mayoclinic.org/diseases-conditions/menorrhagia/symptoms-causes/syc-20352829; ASH 2026 iron deficiency diagnosis guideline (Blood Advances), as summarized at https://www.news-medical.net/news/20261009/New-iron-deficiency-guidelines-raise-key-blood-test-cutoffs.aspx