What to Expect
Perimenopause brings unpredictable menstrual changes as your ovaries produce estrogen and progesterone inconsistently. These changes are among the earliest and most noticeable signs of the hormonal transition.
Key Timeline: Menstrual changes typically begin in your 40s and last 4-10 years. You've reached menopause after 12 consecutive months without a period.
Common Patterns of Change
Cycle Length Variations
- Shorter cycles: Often the first change—cycles may shorten to 21-25 days due to declining progesterone
- Longer cycles: As perimenopause progresses, cycles can lengthen to 35+ days or become irregular
- Skipped periods: Missing one or more cycles, then resuming (not yet menopause unless 12 months pass)
- Unpredictability: No consistent pattern—cycles vary widely month to month
Flow Changes
- Heavier bleeding: More common in early perimenopause due to anovulatory cycles (no ovulation means no progesterone to regulate lining)
- Lighter bleeding: More common in late perimenopause as estrogen declines
- Longer duration: Periods lasting 7-10 days instead of the usual 3-7
- Clots or spotting: Larger clots or mid-cycle spotting between periods
PMS and Mood Symptoms
Hormonal fluctuations can intensify premenstrual symptoms, including mood swings, irritability, anxiety, breast tenderness, and bloating—even if you never had significant PMS before.
When Heavier Bleeding Needs Attention
See your doctor if you experience:
- Soaking through a pad or tampon every 1-2 hours
- Passing clots larger than a quarter
- Bleeding lasting more than 7-10 days
- Bleeding or spotting between periods
- Any bleeding after 12 months without a period
- Symptoms of anemia: severe fatigue, dizziness, shortness of breath, pale skin
Why it matters: While heavier bleeding is common in perimenopause, it can also signal conditions like fibroids, polyps, adenomyosis, or endometrial hyperplasia that require treatment.
Medical Evaluation & Testing
When to Get Evaluated
- Bleeding that soaks through protection in 1-2 hours
- Periods lasting more than 7 days
- Bleeding after 12+ months without a period
- Significant anemia symptoms
- Cycles shorter than 21 days
Common Tests
- Pelvic ultrasound: Checks for fibroids, polyps, ovarian cysts, or thickened uterine lining
- Endometrial biopsy: Rules out precancerous changes or cancer if you have abnormal bleeding, especially if over 45
- Blood tests: Complete blood count (CBC) to check for anemia, thyroid function (TSH), sometimes hormone levels
- Hysteroscopy: Visual exam of the uterine cavity if ultrasound or biopsy suggest polyps or other abnormalities
Management Options
For Heavy or Irregular Bleeding
- Hormonal IUD (Mirena, Liletta): Thins uterine lining significantly; can reduce bleeding by 90%+ and lasts 5-8 years
- Birth control pills: Regulate cycles, reduce flow, and provide contraception if needed
- Progesterone therapy: Cyclic or continuous progesterone to regulate lining shedding
- Tranexamic acid: Non-hormonal medication that reduces bleeding by promoting clotting
- NSAIDs: Ibuprofen or naproxen can reduce flow by 20-30% and help with cramping
Endometrial Ablation
A minimally invasive procedure that destroys the uterine lining to reduce or stop bleeding. Best for women who have completed childbearing and don't respond to medication.
Hysterectomy
Surgical removal of the uterus. Typically reserved for severe cases with failed medical management, significant fibroids, or other structural problems.
Managing Anemia from Heavy Bleeding
Iron Supplementation
- Dose: 65-325 mg elemental iron daily (check with your doctor)
- Timing: Take on an empty stomach with vitamin C for better absorption
- Side effects: Constipation, nausea, dark stools are common—try slow-release formulations if needed
- Follow-up: Recheck CBC and ferritin after 3 months to assess response
Dietary Iron
- Heme iron (better absorbed): Red meat, poultry, fish
- Non-heme iron: Beans, lentils, spinach, fortified cereals—pair with vitamin C for absorption
- Avoid with meals: Caffeine, calcium, and tannins in tea can reduce iron absorption
Tracking Your Cycles
Why tracking helps:
- Identifies patterns in cycle length and flow changes
- Provides concrete data for your doctor
- Helps distinguish between normal perimenopause and abnormal bleeding
- Assists with contraception planning if still needed
What to Track
- Cycle start date: First day of bleeding
- Flow heaviness: Light, moderate, heavy, very heavy (soaking through products)
- Duration: Number of days bleeding
- Clots: Size and frequency
- Spotting: Any bleeding between periods
- Associated symptoms: Cramping, fatigue, mood changes
Contraception Considerations
You can still get pregnant during perimenopause! Irregular cycles don't mean you're not ovulating. Contraception is recommended until you've gone 12 months without a period (menopause).
Options That Also Manage Bleeding
- Hormonal IUD: Highly effective contraception + reduces bleeding significantly
- Birth control pills: Reliable contraception + regulates cycles and reduces flow
- Progestin-only pill or implant: Good for women who can't take estrogen
Note: After age 50-55, if you've had no periods for 12 months, contraception is typically no longer needed.
What's NOT Normal
These symptoms warrant immediate medical attention:
- Bleeding after menopause (12+ months without a period)
- Sudden, very heavy bleeding with dizziness or fainting
- Severe pelvic pain with bleeding
- Foul-smelling discharge with bleeding
- Fever with abnormal bleeding
The Bottom Line
Menstrual changes are a hallmark of perimenopause and can vary widely. While many patterns are normal, heavy or prolonged bleeding should be evaluated to rule out other conditions and prevent anemia. Effective treatments exist—both hormonal and non-hormonal—to manage symptoms and improve quality of life during this transition.
When in doubt, get checked out. It's always better to have peace of mind than to assume heavy or irregular bleeding is "just perimenopause."