Estrogen & Progesterone Levels by Menstrual Cycle Phase
Your hormone levels change dramatically throughout your menstrual cycle. Reference ranges come from large population studies (NHANES, WHO) and provide a framework for interpreting your results, but your personal health history always matters most. Track estrogen and progesterone across all cycle phases with values updated as of 2026.
When to use this calculator
- Understanding hormone fluctuations throughout your menstrual cycle
- Tracking fertility and cycle-based family planning
- Interpreting lab results for estrogen and progesterone tests
- Learning about hormonal patterns and reproductive health
- Quick reference for healthcare providers and students
Example Calculation
- Day 14
- Ovulatory Phase
How it works
1 min readHow Estrogen and Progesterone Fluctuate Across Your Cycle
Estrogen and progesterone levels change significantly throughout your menstrual cycle. Reference ranges come from large population studies (NHANES, WHO) and vary by age, reproductive stage, and individual factors. These ranges provide context for interpreting your results, but your personal health history always takes precedence.
How It Works
This calculator uses a phase-based lookup table. Enter your cycle day and see the typical estrogen and progesterone levels expected during that phase. It applies direct calculation with established reference ranges, helping you understand where you fall in the normal spectrum.
Typical Hormone Ranges by Cycle Phase
| Hormone | Phase | Typical Range |
|---|---|---|
| Estrogen (E2) | Follicular | 30–100 pg/mL |
| Estrogen (E2) | Ovulatory | 200–600 pg/mL |
| Estrogen (E2) | Luteal | 50–150 pg/mL |
| Progesterone (P4) | Follicular | <1 ng/mL |
| Progesterone (P4) | Ovulatory | <1 ng/mL |
| Progesterone (P4) | Luteal | 5–20 ng/mL |
| FSH (Day 3) | Baseline | 4–9 mIU/mL |
| LH | Baseline | 2–10 mIU/mL |
Important Notes
This calculator provides reference values for educational purposes. Hormone levels vary significantly based on age, medications, health conditions, and individual variation. For any medical concerns or decisions, consult with a healthcare provider who can interpret your specific results in context with your symptoms and personal health history.
Frequently asked questions
What are the four phases of the menstrual cycle?
Menstrual (days 1–5): shedding of the uterine lining; Follicular (days 1–13): follicles grow and estrogen rises; Ovulatory (day 14): LH surge triggers egg release; Luteal (days 15–28): progesterone dominates.
When does estrogen peak during my cycle?
Estrogen peaks around days 12–13, just before ovulation. This surge triggers the LH surge that causes ovulation.
When is progesterone at its highest?
Progesterone peaks around day 21 during the mid-luteal phase, when the corpus luteum is most active after ovulation.
How are estrogen and progesterone measured?
Both are measured via blood test. Estrogen (E2) and progesterone (P4) are typically checked on day 3 (baseline) and day 21 (post-ovulation) to assess ovarian function.
What is FSH and why does it matter?
Follicle-stimulating hormone (FSH) triggers follicle growth and estrogen production. It's typically measured on day 3. Levels >10 mIU/mL may suggest lower ovarian reserve.
What does an LH surge mean?
Luteinizing hormone (LH) surge triggers ovulation. It's the basis for ovulation predictor tests. The surge occurs 24–36 hours before ovulation.
What counts as an irregular menstrual cycle?
Cycles shorter than 21 days or longer than 35 days are generally considered irregular and may warrant evaluation by a healthcare provider.
When should I see a doctor about my cycle hormones?
See a doctor if hormone levels fall outside normal ranges, if you have concerning symptoms, if cycles are irregular, or if there's family history of reproductive or metabolic conditions.