How do periods change during perimenopause?

As ovulation becomes less predictable, the number of days between periods can shorten or lengthen. Bleeding may last more or fewer days, become lighter or heavier, and vary from one cycle to the next. Some periods may be skipped before bleeding returns.

There is no single required sequence. A changed cycle does not confirm perimenopause by itself, and the amount of bleeding should not be dismissed because the change happened in the 40s. Age, pregnancy possibility, contraception, medicines, symptoms and the effect on daily life all matter.

Use a calendar, app or private notes if that is manageable. Record the first day of bleeding, how many days it lasts, spotting between periods or bleeding after sex, and whether periods are closer together, further apart or skipped. For flow, note how often products need changing, flooding, leaking through clothes or bedding, clots, night changes and any effect on work, sleep or leaving home.

Also note pain, fatigue, dizziness, breathlessness, pregnancy possibility, contraception and medicine changes. You do not need months of perfect records before asking for help.

Pregnancy, hormonal contraception, other medicines, thyroid problems, fibroids, polyps, adenomyosis, endometriosis, infection and changes in the lining of the uterus, including less commonly cancer, can change bleeding. The pattern alone cannot tell you which explanation applies.

If pregnancy is possible and a period is late or unusual, take a pregnancy test or seek advice rather than assuming the change is perimenopause. One-sided pelvic pain, shoulder-tip pain, bleeding, dizziness or fainting with possible pregnancy needs urgent in-person assessment.

The endometriosis guide explains when pain, bowel or bladder symptoms, pain during sex and bleeding may deserve a broader assessment.

A GP can ask about the pattern, pelvic pain, pregnancy possibility, contraception, medicines, cervical screening, previous procedures and relevant family history. An examination may help in some situations and requires your consent; you can ask why it is suggested, what it involves and what alternatives are available.

Testing is guided by the history. Pregnancy testing may be needed. For heavy menstrual bleeding, a full blood count and ferritin help assess anaemia and depleted iron stores. Other blood tests, ultrasound or referral may be useful when the pattern suggests another cause; not everyone needs the same panel or scan.

Ask what each test is checking, who will review the result and what happens next. The iron-studies guide explains how ferritin differs from haemoglobin and other iron results.

Ovulation can still occur during perimenopause, even when periods are irregular or have been missed. Menopausal hormone therapy is not contraception. Some contraceptive methods change or stop bleeding, so period history may not show whether menopause has occurred.

If pregnancy is possible and not wanted, discuss how long to continue contraception and which method fits your health and preferences. Do not stop or change contraception to interpret a bleeding pattern without a plan. The choosing contraception guide can help prepare the questions to ask.

The useful option depends on the cause, bleeding pattern, pain, iron status, contraception needs, pregnancy plans, health history and preferences. Support may include treating iron deficiency, medicine to reduce bleeding or pain, a hormonal option, changing contraception, or a procedure when a structural cause is found. No single option suits every pattern.

Ask what an option aims to improve, its likely unwanted effects, whether it provides contraception and when to review it. Continued or worsening bleeding deserves reassessment rather than repeating an ineffective plan indefinitely.

Sources supporting this guide. Source organisations have not reviewed or endorsed HerDoc.