Perimenopause cycle changes and heavy bleeding: what is normal and what actually helps

The short version

• Erratic cycles are the diagnostic hallmark. A persistent difference of seven days or more between consecutive cycle lengths marks early perimenopause; gaps of 60 days or more mark the late stage.
• Heavy bleeding is usually anovulatory. No ovulation means no progesterone phase, so the lining keeps thickening under estrogen and then sheds heavily and unpredictably.
• New or heavy bleeding over 45 gets investigated. Pelvic ultrasound and, in most cases, an endometrial biopsy, because the risk of hyperplasia and endometrial cancer rises with age.
• The hormonal coil is first-line medical treatment. It typically cuts blood loss by around 70 to 90 percent, and it doubles as contraception and as the progestogen half of HRT.
• Ablation is a legitimate, often excellent option. Day case, high satisfaction, but only after the cavity and lining are assessed, only once your family is complete, and contraception must continue.
• Replace the iron. Ask for ferritin. Low iron causes a large share of the fatigue and breathlessness blamed on hormones.

What changes, and in what order

Clinicians stage the transition using the STRAW+10 framework, and cycle pattern is the main marker. It usually unfolds like this:

1. Cycles get shorter first. Many women notice periods arriving every 24 or 25 days instead of 28, because the follicular phase compresses as the ovarian reserve falls. Shorter cycles mean more periods per year, which alone makes bleeding feel relentless.
2. Variability arrives. A difference of seven days or more between one cycle and the next, repeated, is the formal signature of early perimenopause. One month 23 days, the next 34.
3. Cycles start skipping. In late perimenopause you get gaps of 60 days or more. Skipped cycles are usually anovulatory, and the period that follows a long gap is often the heaviest one.
4. Flow character changes. Heavier days, more clotting, a longer tail of spotting, and a less predictable ramp-up. Some women swing the other way into much lighter, shorter bleeds, which is also normal.
5. Then it stops. Menopause is confirmed retrospectively after 12 consecutive months with no bleeding.

Why the bleeding gets heavy: the biology, simply

In an ovulatory cycle, estrogen builds the lining in the first half, then the corpus luteum produces progesterone, which stabilises that lining and organises an orderly bleed when it withdraws. Perimenopause disrupts the second half of that story.

• Ovulation becomes intermittent. Fewer, less responsive follicles mean some cycles never ovulate. No corpus luteum, no progesterone.
• Estrogen is erratic, not simply low. FSH rises and drives occasional very high estrogen surges. Early perimenopause is better described as hormonal turbulence than as deficiency.
• Unopposed estrogen keeps building lining. A thicker, less structurally supported endometrium eventually breaks down without the coordinated signal that normally limits blood loss.
• Local clotting control shifts. Heavy menstrual bleeding involves increased local fibrinolysis and altered prostaglandins in the lining, which is precisely why tranexamic acid and anti-inflammatories work.
• Structural problems amplify everything. Fibroids and adenomyosis increase the surface area and impair contraction of the womb, and they are common in the exact decade this is happening.

Red flags: see a doctor about these, not the internet

• Any bleeding more than 12 months after your last period
• Bleeding between periods or after sex
• Cycles consistently shorter than 21 days, or bleeds longer than 7 days
• Soaking a pad or tampon hourly for several hours, or passing clots bigger than a quarter
• Dizziness, breathlessness on mild exertion, chest pain, or fainting with bleeding, which needs urgent assessment
• New heavy bleeding when you have risk factors for endometrial hyperplasia, including a higher BMI, polycystic ovary syndrome, diabetes, tamoxifen use, or a family history of Lynch syndrome

Guidance for abnormal uterine bleeding in women over 45 is to assess the endometrium rather than treat blind, typically with a transvaginal ultrasound and an endometrial biopsy, plus a full blood count and ferritin, thyroid function if there are other pointers, and clotting studies if you have bled heavily since your very first period. Most of these tests come back reassuring. They exist so treatment can proceed confidently.

The PALM-COEIN checklist your clinician is working through

Treatment, in the order it is usually offered

1. Fix the iron. Oral iron, ideally alternate days with vitamin C and away from tea, coffee, and calcium, which improves absorption and tolerance. Intravenous iron if you cannot absorb or tolerate tablets. Recheck ferritin after around three months.
2. Tranexamic acid on bleeding days only. A non-hormonal tablet that reduces blood loss meaningfully, taken for the heavy days rather than continuously. It does not affect your cycle or your fertility.
3. An NSAID such as mefenamic acid or naproxen. Reduces both flow and period pain, and can be combined with tranexamic acid. Not for anyone with ulcers or certain kidney problems.
4. The levonorgestrel intrauterine system. Recommended as first-line long-term medical treatment for heavy menstrual bleeding, with typical reductions in blood loss of roughly 70 to 90 percent. Expect irregular spotting for the first three to six months before it settles. It also provides contraception and can serve as the progestogen component alongside estrogen for perimenopausal HRT.
5. Combined hormonal contraception. Regulates cycles, reduces flow, and manages hot flashes in one, for women without contraindications such as migraine with aura, smoking over 35, uncontrolled hypertension, or a history of clots.
6. Cyclical or continuous progestogen. Norethisterone from day 5 to 26 can control bleeding short term, and progestogens protect the lining, but a coil generally outperforms tablets for heavy bleeding.
7. Targeted fibroid treatment. Hysteroscopic resection of submucosal fibroids, uterine artery embolisation, myomectomy, or GnRH-analogue based medication to shrink fibroids before surgery.
8. Endometrial ablation. See below.
9. Hysterectomy. Definitive, and the right answer for some women, especially with large fibroids, adenomyosis with severe pain, or failed ablation. Keeping the ovaries where possible avoids surgical menopause.

One important caveat: estrogen-only HRT does not treat heavy bleeding, and if you have a womb, estrogen must always be paired with adequate progestogen or a hormonal coil to protect the lining.

Endometrial ablation, honestly

Ablation uses radiofrequency, heated fluid, or another energy source to destroy the lining of the womb, usually in under ten minutes as a day case, often under local anaesthetic with sedation. For women whose bleeding is the problem and whose cavity is a normal shape, published outcomes and guideline reviews consistently report high satisfaction, with most women reporting light bleeding or none at all, and far fewer hysterectomies than would otherwise be needed. Many women describe it as the intervention that gave them their life back. That reputation is earned.

It is not right for everyone, and the conditions are not fine print:

• The lining must be assessed first. Ablation destroys the tissue a pathologist would need, so imaging and biopsy come before, never after.
• Your family must be complete. Pregnancy after ablation is uncommon but carries serious risk, so effective contraception must continue afterwards, and sterilisation or a coil is often discussed at the same time.
• It treats bleeding, not pain. Results are less reliable if adenomyosis and pain are the dominant problem.
• Cavity size and shape matter. A large or distorted cavity, or significant fibroids, reduces success rates.
• It can need repeating. A minority of women go on to have a second procedure or a hysterectomy, and younger age at ablation is associated with higher rates of later surgery.
• Future bleeding becomes harder to read. Scarring can trap blood and can make later endometrial assessment more difficult, so any new bleeding after ablation must be reported promptly rather than dismissed.
• It is not contraception and not HRT. If you take estrogen afterwards and still have a womb, you still need endometrial protection.

A two-cycle tracking protocol

Bleeding is the one perimenopause symptom you can quantify, which makes it the most persuasive thing you can bring to an appointment.

1. Log every bleeding day. Date, flow rated light, moderate, heavy, or flooding, and any spotting between bleeds.
2. Count products. Number of pads, tampons, cup empties, or period pants changed per day, and whether you needed double protection or a change overnight.
3. Note clots and accidents. Clot size compared with a coin, and any leak-through that affected work, sleep, or plans.
4. Track cycle length gaps. First day of bleeding each time, so the seven-day variability signature and any 60-day gaps are visible.
5. Record the knock-on symptoms. Fatigue, breathlessness on stairs, dizziness, palpitations, hair shedding, and pain scores.

What to say at the appointment

"I'm [age] and my cycles have changed over the last [X] months: they range from [shortest] to [longest] days, and I've had [N] bleeds lasting more than seven days. On the heaviest days I change protection every [N] hours and I'm passing clots. It has caused [work absence / accidents / cancelled plans]. I feel [exhausted / breathless on stairs / light-headed]. I'd like a full blood count with ferritin, a pelvic ultrasound, and an endometrial biopsy given my age, and then I'd like to discuss tranexamic acid, a hormonal coil, and whether ablation is appropriate for me."

If you are told to simply wait it out, it is reasonable to ask two questions: what has been done to exclude a structural or endometrial cause, and which treatment on the standard ladder is being offered while we wait. Heavy bleeding can run for years before periods stop. That is a long time to plan your life around a bathroom.

How PeriSlayer connects this to the wider pattern

Cycle chaos is the hardest thing to hold in your head, because the pattern only appears across months. PeriSlayer logs bleeding days, flow, clots, and product counts alongside your sleep, mood, pain, energy, and palpitations, then surfaces the correlations you would never spot manually, like the anovulatory long gap that reliably precedes your worst bleed, or the fatigue that tracks your iron rather than your age. It rolls all of it into an appointment summary with dates, cycle lengths, and severity, so the conversation starts with evidence instead of apology.