Issue 032

Heavy periods in your 40s: what is normal and what needs a workup

Yvette Rose · 8 min read

Somewhere after 40 a lot of women find their periods have turned into an event. Closer together, longer, heavier, with clots, and a week every month planned around the bathroom. Most have been told this is perimenopause and to wait it out. Perimenopause does make periods heavier. It does not get to be the explanation until the other causes have been looked at, because fibroids, polyps, a thyroid tested at TSH alone, a bleeding disorder you were born with and a lining that has grown too thick all look the same from the outside, and one of them needs a biopsy. This note is what counts as too much, why it happens, and the workup I ask every woman to get.

What counts as heavy

The textbook number is more than 80 millilitres a cycle, which nobody measures, so here is how I ask it. Do you soak through a pad or tampon every hour for 2 or more hours in a row. Do you pass clots bigger than a quarter. Do you bleed for more than 7 days. Do you double up, or get up at night to change. Do you plan around it. A yes to any of those is heavy, and heavy that affects your life is the definition the guidelines actually use.

Then I ask about the pattern, because the pattern is a different question. Cycles under 21 days. Bleeding between periods. Bleeding after sex. Any bleeding at all after 12 months without a period, which is never normal and always needs to be seen. A heavier version of your usual period is one conversation. A new pattern is the one that gets a scan.

Why perimenopause does this

In your reproductive years you ovulate most months, and after you ovulate your body makes progesterone. Progesterone is what tells the lining to stop growing and then to shed in an orderly way. In perimenopause you start to skip ovulation, sometimes without knowing, because you still bleed. A cycle with no ovulation has estrogen and no progesterone. The lining keeps building for weeks, then comes down all at once, late and heavy and in pieces.

That is the mechanism behind most heavy bleeding in the forties, and it is why the cycle that was 28 days becomes 24 and then 45 and then 19. The hormones are swinging and the uterus is doing exactly what it is told. It is also why a lining that gets estrogen without progesterone for a long time needs a doctor's eye, because that is the setup for the lining to overgrow.

The things that are not perimenopause

Fibroids are first. They are benign muscle growths in the uterus, extremely common by 50, and the ones near the lining cause exactly this picture. Polyps are small growths on the lining that bleed between periods. Adenomyosis is lining tissue growing into the muscle wall, and it gives heavy painful periods and a tender, bulky uterus. All 3 show on a transvaginal ultrasound, the first test after the exam.

Then the blood itself. A meaningful share of women with heavy periods have a mild inherited bleeding disorder, most often von Willebrand disease, and most were never tested because their heavy periods started at 13 and everyone said that was normal. If you bruise easily, bled a lot after dental work or childbirth, or your mother and sister bleed the same way, say so. Blood thinners and some antidepressants and anti inflammatory drugs make bleeding heavier too.

Then the thyroid. An underactive thyroid makes periods heavier and more frequent, and a TSH alone can miss it. I want TSH, free T4 and antibodies on anyone with new heavy bleeding, for the reasons in Issue 011.

Then the one nobody wants to name, which is a lining that has overgrown or turned. It is uncommon, it is more likely with obesity, diabetes, PCOS or long stretches of estrogen without progesterone, and the guidance is clear that any woman 45 or older with abnormal bleeding should have the lining sampled. That is an office biopsy, 5 minutes, uncomfortable and over. I would rather you have it and hear benign than skip it and wonder.

Heavy is common in your forties. Common is not the same as explained.

What the bleeding is doing to the rest of your folder

Here is where my reading of the panel starts. A woman losing that much blood every month cannot keep up her iron from food. Her ferritin slides to 12, gets called normal because the range starts at 10 or 15, and she is told her fatigue is stress. The American Society of Hematology updated its guidance in 2026. Iron deficiency is now a ferritin of 30 or lower, and for women with heavy periods a cutoff of 50 may be used. Low ferritin is the thread that connects the heavy period to the hair loss, the breathlessness on stairs, the restless legs and the brain fog, and it is often the only abnormal result on a page nobody reads as a whole.

Low iron then feeds back. An iron deficient body runs a slower thyroid, a flatter mood and a nervous system that feels under threat, the state I write about in Issue 019. The way out is to stop the loss and replace the iron, in that order, and both of those are your doctor's.

The mother question

Before I ask about your diet I ask about your mother. When did her periods stop. Did she have fibroids or a hysterectomy, and does she know why. Did she bruise and bleed easily. Fibroids, early menopause and bleeding disorders all run in families, and that is biology you inherited and should hand to your doctor.

Then I ask what she taught you about bleeding. A lot of women were raised in a house where heavy, painful periods were what women got and complaining was weakness. That is a pattern you inherited, a separate problem from the biology, and often the reason a woman is 46 before anyone looks.

What I ask people to get

I ask them to write down the last 3 cycles before the appointment. Start date, length, how many products on the heaviest day, clots, bleeding between, and how you felt the week after. A doctor can act on that in a way she cannot act on "heavy."

I ask for a blood count and a ferritin, and for the ferritin to be read against 30, or 50 given the bleeding. The bottom of the lab range is the wrong line. If iron is low, iron is prescribed and dosed by the doctor. Taking it every other day absorbs better than daily for many women, it goes 4 hours away from thyroid medication, and it will make you constipated, which is worth planning for.

I ask for a full thyroid panel, TSH, free T4 and antibodies, and a pregnancy test, because perimenopause is a time women are told they cannot conceive and some of them do.

I ask for a pelvic exam and a transvaginal ultrasound to look for fibroids, polyps and adenomyosis, and for the thickness of the lining.

I ask for the biopsy if you are 45 or older, or younger with obesity, PCOS, diabetes, or bleeding that has not responded to treatment. And I ask for a bleeding disorder screen if there is a history of easy bruising or a family pattern.

Then I ask them to talk through the options with a doctor who treats this, because there are good ones. A hormonal IUD cuts bleeding by 71 to 95 percent and is the most effective medical treatment. Tranexamic acid, taken only on bleeding days, cuts it by a quarter to a half, and is off the table for anyone with a history of clots. Naproxen on bleeding days helps some women. The pill and cyclic progesterone regulate the lining. If hot flashes have arrived alongside, hormone therapy is the most effective treatment for those, and that whole conversation belongs with a menopause trained doctor. If you are on blood thinners, diabetes medication or thyroid medication, every one of these is a prescriber decision. I do not prescribe any of it. I help you walk in with the folder in order and the questions written down. The Whole Reset workbook has the cycle tracker and the iron rich recipes if you want them on paper, at $49 with shipping.

When to push harder with your doctor

Soaking through a pad or tampon every hour for more than 2 hours, feeling faint, dizzy or short of breath, or bleeding that will not stop needs same day care. That is an emergency room visit. A message to the office is for the next day.

Any bleeding after 12 months without a period needs to be seen within weeks, whatever anyone tells you about spotting.

If you are 45 or older with new heavy or irregular bleeding and nobody has offered to sample the lining, ask why.

If you have been told it is perimenopause without an ultrasound, a blood count, a ferritin and a full thyroid panel, ask for all 4 before you accept the wait.

If your ferritin is under 30 and you were told it is normal, show them the 2026 guidance and ask again.

FAQ

Are heavy periods normal in perimenopause?

Heavier periods are common in perimenopause because you skip ovulation and the lining builds up without progesterone. Common is different from explained. Fibroids, polyps, thyroid problems, bleeding disorders and an overgrown lining all cause the same picture, so a workup comes before the wait.

How much bleeding is too much?

Soaking a pad or tampon every hour for 2 or more hours, clots bigger than a quarter, bleeding longer than 7 days, cycles under 21 days or bleeding between periods. Any bleeding after a year without a period is never normal.

What tests should I ask for with heavy periods?

A blood count, ferritin, a full thyroid panel with free T4 and antibodies, a pregnancy test and a transvaginal ultrasound. If you are 45 or older, an endometrial biopsy. If you bruise or bleed easily, a bleeding disorder screen.

Can heavy periods cause low ferritin?

Yes, and it is the most common reason for low ferritin in women under 50. The 2026 hematology guidance calls a ferritin of 30 or lower deficient and allows 50 as a cutoff for women with heavy bleeding. If yours was called normal at 15, ask again.

What is the best treatment for heavy periods?

The hormonal IUD cuts bleeding the most, by 71 to 95 percent. Tranexamic acid and naproxen on bleeding days help many women. The right one depends on the cause, your clot risk and whether you want to conceive, which is a conversation with a gynecologist or menopause trained doctor.

In good health,
Yvette Rose

Sources

This is general wellness education and not medical advice, diagnosis or treatment. Talk to a qualified professional, especially if you are pregnant, nursing, taking medication or managing a condition.

It all starts in the gut.