Hormone Levels During Menstrual Cycle

Key Differences in Perimenopausal Hormones

• Shorter cycle length: Typically 21-26 days vs 28-30 days in younger women
• Lower estradiol peaks: About 40-60% lower than in younger women
• Reduced progesterone: Often insufficient luteal phase progesterone
• Earlier follicular development: Follicular phase can be shortened
• Testosterone decline: Gradual decline by 10-30% compared to peak reproductive years
• More variable cycles: Increased cycle length variability and unpredictability

Common Perimenopausal Symptoms Due to Hormone Changes

• Hot flashes and night sweats (due to estrogen fluctuations)
• Sleep disturbances (due to progesterone insufficiency)
• Mood changes (related to estrogen's effects on serotonin and dopamine)
• Irregular periods (due to irregular ovulation)
• Decreasing fertility (due to declining egg quality and quantity)
• Changes in libido (related to both estrogen and testosterone levels)

Tracking Your Cycle

Understanding your personal hormone patterns can help you:

• Predict your periods and fertility windows
• Understand mood changes throughout your cycle
• Manage symptoms by timing interventions with your cycle
• Recognize when your cycle patterns change as you age
• Have informed conversations with healthcare providers

How to Use This Tool

1. Use the buttons at the top to toggle between viewing hormone levels for different age groups.
2. Observe how hormone levels change throughout a typical 28-day cycle.
3. Note the differences between hormone patterns in younger (20-year-old) and perimenopausal women.
4. Refer to the symptom information to understand how hormonal changes may affect your body.
5. Use this knowledge to track your own cycle patterns and identify any changes over time.