Perimenopause periods: shorter, heavier, or skipped cycles explained

How periods change through perimenopause

Perimenopause can begin up to 10 years before your last period. In the US, the average age of menopause is 52, so many women notice changes in their early to mid 40s.

Early perimenopause

Cycles still come, but they start to change. A common early sign is cycles that get shorter, say every 23 days instead of 28, or that vary by a week or more from one month to the next. Periods may be lighter some months and much heavier others. PMS-type symptoms like breast tenderness, mood swings, and bloating can get stronger.

Late perimenopause

Ovulation becomes less frequent, so you start skipping periods, sometimes for two months or more. When a period does come after a long gap, it can be very heavy. Hot flashes and sleep problems are often more noticeable at this stage.

Menopause

Menopause is one point in time: 12 months in a row without a period. After that, you're postmenopausal.

Why periods get heavier

In a typical cycle, ovulation is followed by a rise in progesterone, which keeps the uterine lining in check. In perimenopause, many cycles happen without ovulation. Estrogen keeps building the lining without enough progesterone to balance it, so when the lining finally sheds, the period can be heavier and longer.

Conditions that become more common in your 40s, such as fibroids and polyps, can also cause heavy bleeding, which is one reason to get changes checked.

Bleeding that needs a doctor

Irregular periods are expected, but some changes should be checked:

• Bleeding so heavy you soak through a pad or tampon in an hour or two, or pass large clots
• Periods that last more than seven days
• Periods that come more often than every 21 days
• New spotting or bleeding between periods, or after sex
• Feeling dizzy, short of breath, or very tired, which can be signs of low iron from blood loss
• Any bleeding after you've gone 12 months without a period

Tips for managing the changes

1. Track your cycle. An app or a simple calendar note showing start dates, flow, and symptoms helps you spot patterns and gives your doctor clear information.
2. Be ready for heavier days. Overnight pads, period underwear, or a menstrual cup can help with unpredictable flow.
3. Ask about iron levels. Heavy periods can lead to iron deficiency, which causes fatigue, brain fog, and shortness of breath.
4. Know that treatment exists. If heavy bleeding is affecting your life, there are options, including medications and hormonal treatments. A doctor can help you choose.
5. Keep using contraception if you need it. You can still get pregnant in perimenopause, even with irregular periods. Talk to your doctor about when it's safe to stop.