Heavy periods in perimenopause: when to worry, what to do

What is normal in perimenopause, and what is not

In perimenopause, ovulation becomes irregular. Cycles shorten, then lengthen, skip a turn, come back. That disorder is the very definition of the transition: there is nothing worrying about it in itself.

What does not fall into that category is the volume. Having to double up on protection, change every hour, get up at night to avoid an accident, give up going out for two days, passing clots the size of a coin: this is not "perimenopause doing its job". It is abnormally heavy bleeding, and it has identifiable causes.

The definition used by learned societies has in fact changed its logic. It no longer rests on milliliters measured in a laboratory, but on the impact: bleeding is excessive as soon as it interferes with quality of life, whatever the absolute volume³. In other words, your discomfort is part of the criterion. You do not have to prove anything before speaking up.

The possible causes, and why guessing is impossible

The international classification used by gynecologists the world over (the FIGO system, revised in 2018) separates the causes into two groups¹.

On one side, the structural causes: those you can see on imaging. Endometrial polyp, adenomyosis, fibroid, and (more rarely) a precancerous lesion or endometrial cancer. One point matters particularly after 45: polyps and fibroids become more frequent with age, which mechanically explains part of the rise in abnormal bleeding in perimenopause².

On the other, the non-structural causes: clotting disorders, endocrine causes, effects of a treatment, and above all disordered ovulation. It is this last mechanism that is most typical of perimenopause. When ovulation does not happen, there is no progesterone to counterbalance estrogen; the endometrium thickens without being stabilized, then sheds in a disorderly and heavy way.

These two families produce exactly the same symptom. That is the whole difficulty, and the reason why no article (this one included) can tell you what is going on in your case.

The work-up: what to expect

The approach is well codified. The speculum examination first rules out a cause in the cervix or the vagina. Pregnancy must be excluded: yes, still, as long as periods have not stopped for twelve months. Depending on the context, a blood test measures hemoglobin and iron, and sometimes thyroid hormones².

A useful clarification for France. The 2022 CNGOF recommendations call for a complete blood count, whose first aim is to detect anemia. On the other hand, they do not settle the question of systematically adding a ferritin measurement, for lack of a study comparing the two strategies: it is therefore not a test to demand as a matter of principle, but a discussion to have with your doctor. Those same recommendations do, however, ask for something often forgotten: in an adult woman whose ultrasound is normal, a clotting work-up and a search for von Willebrand disease are recommended, a clotting disorder that can go unnoticed for years.

Next comes transvaginal ultrasound, described as the ideal first examination. A variant, ultrasound with saline instillation, improves diagnostic accuracy when a lesion inside the cavity is suspected. It is the result of this imaging that determines what comes next: endometrial biopsy, hysteroscopy, or simple monitoring².

Here too, the CNGOF gives precise benchmarks, and it is useful to know them in order to understand what is being offered to you. Endometrial biopsy is recommended when the endometrium measures 15 mm or more on ultrasound, and it is also recommended in the presence of risk factors for endometrial cancer, regardless of that thickness. So if a biopsy is proposed to you, it does not necessarily mean something worrying has been seen: most often it is the application of a criterion.

A word on what this work-up seeks to rule out. Endometrial cancer is the fear that drives women, rightly, to seek care. It has to be said in the right words: only a minority of women who consult for abnormal bleeding have a precancerous or malignant lesion⁶. That is not a reason not to look, it is a reason not to panic while waiting for the appointment.

The treatments with established effectiveness

Once the serious causes have been ruled out, treatment is decided with you, according to your discomfort, your age, your wish for a pregnancy and your history. The question "what works best?" has received a fairly clear answer.

In 2022, a vast Cochrane overview compared all the available treatments with one another, in a network meta-analysis. Its conclusion, for first-line treatments: the levonorgestrel hormonal intrauterine device is the most effective at reducing bleeding volume; antifibrinolytics probably come second, and progestogens taken on a long cycle likely third³. The authors remain cautious on one point: they cannot draw a conclusion about perceived satisfaction, the certainty of the evidence being very low on that outcome.

Tranexamic acid, that antifibrinolytic, has the advantage of being taken only during the days of bleeding. A systematic review of ten studies reports a reduction in bleeding volume of 34 to 54%, with an improvement in quality of life of 46 to 83%, versus 15 to 45% on norethisterone. No thromboembolic event was reported in the studies analyzed⁴. One caution, though: this reassuring result is not a green light for everyone. The CNGOF points out that tranexamic acid is contraindicated in case of a history of venous or arterial thromboembolism, as well as in the presence of thromboembolic risk factors. It is a contraindication, not a simple precaution, and it is a reason never to take a box lent by a friend.

The CNGOF also confirms the ranking that comes out of the international data: in a woman who is not planning a pregnancy in the short term, the levonorgestrel 52 mg intrauterine device is recommended as first choice; when a pregnancy is planned in the short term, it is non-hormonal treatments, antifibrinolytics first, that are offered first.

When these treatments are not enough, so-called second-line options come in. One trial directly compared the hormonal intrauterine device with endometrial ablation: both are defensible choices, and the device has the advantage of being reversible⁵. Hysterectomy remains the most effective treatment for the bleeding, but it is also the heaviest, and it comes at the end of the chain³. When a fibroid is the cause, management has broadened markedly in recent years and no longer comes down to surgery⁷.

Two things often forgotten

Iron. Heavy periods month after month drain the stores. The fatigue that follows is often blamed on hormones when it has a simple, correctable cause. It is a frequently missed link: we detailed it in our article on fatigue in perimenopause. Always test before any supplementation.

Contraception. As long as ovulation has not definitively stopped, pregnancy remains possible, including with very irregular cycles. Some treatments for heavy periods in fact serve both functions at once⁸. It is a conversation to have explicitly with your doctor, because it is rarely opened spontaneously.

When to see a doctor without delay

Some signs are not a matter for watchful waiting:

• bleeding that soaks through a pad in less than an hour, for several hours in a row;
• signs of anemia: unusual breathlessness, palpitations, pallor, dizziness, exhaustion;
• bleeding between periods, or after intercourse;
• any bleeding occurring after twelve months without periods, that is to say after menopause: that one is always investigated. The CNGOF and GEMVi recommendations are unambiguous on this point: faced with abnormal bleeding in a postmenopausal woman, it is recommended to look for an organic cause, with a pelvic ultrasound and, if the bleeding recurs or if the endometrium is thickened, a hysteroscopy and an examination of the tissue.

And one situation that is not up for discussion: bleeding that puts you in difficulty right away. Massive bleeding accompanied by faintness, dizziness on standing, unusual pallor, a racing heart or breathlessness on the slightest effort is an emergency: call 15, or 112 from a mobile phone. Heavy hemorrhage can make hemoglobin drop within a few hours, and you do not wait for an appointment in that situation.

In short

Perimenopause throws cycles off, that much is agreed. But it obliges nobody to organize their life around their periods. Bleeding that bothers you deserves to be investigated: the work-up is simple, the causes are most often benign, and effective treatments exist, with a fairly clear ranking of what works best. The only bad decision here is to wait, telling yourself it is normal.

⚠️ This article is provided for informational and educational purposes only. It does not replace medical advice, diagnosis or treatment. Always consult your doctor or a qualified health professional with any questions about your health.

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