What are normal estradiol (estrogen) levels in women, measured in picomoles per liter (pmol/L)?

Normal Estradiol Levels in Women (pmol/L)

Normal estradiol levels in women vary significantly by age, menstrual cycle phase, and menopausal status, with reference intervals ranging from <26 pmol/L in postmenopausal women to as high as 2864 pmol/L during the LH peak in premenopausal women. 1

Reference Intervals for Premenopausal Women (by Menstrual Cycle Phase)

Estradiol levels fluctuate predictably throughout the menstrual cycle:

• Early follicular phase (days -15 to -6): 31-771 pmol/L
• Late follicular phase (days -5 to -1): 104-1742 pmol/L
• LH peak (day 0): 275-2864 pmol/L
• Early luteal phase (days +1 to +4): 95-1188 pmol/L
• Mid-luteal phase (days +5 to +9): 151-1941 pmol/L
• Late luteal phase (days +10 to +14): 39-1769 pmol/L 1

Reference Intervals for Other Female Groups

• Postmenopausal women: <26 pmol/L 1
• Women on hormone therapy: 54.62-2050.55 pmol/L (wide variation depending on dose, delivery method, and individual factors) 2

Clinical Considerations

Factors Affecting Estradiol Levels

• Age: Younger women typically have higher estradiol levels and greater variance in those levels compared to older women 2
• Delivery method: When using hormone therapy, patch users tend to have lower and more consistent levels compared to gel users who show greater variance 2
• Individual absorption: Approximately 25% of women using the highest licensed dose of transdermal estradiol still have subtherapeutic levels (<200 pmol/L) 2

Measurement Considerations

• Timing: For accurate assessment of ovarian reserve in premenopausal women, estradiol measurement should ideally be performed between days 2-4 of the menstrual cycle 3
• Method: LC-MS/MS methods provide the most accurate and traceable measurements of estradiol, especially at the lower concentrations seen in postmenopausal women and men 1, 4
• Hormone therapy: When monitoring women on hormone therapy, significant interindividual variation exists, and serum measurements can help identify those who may benefit from dose adjustments 2

Clinical Significance

• Estradiol levels below 35-55 pg/ml (approximately 128-202 pmol/L) in postmenopausal women may be insufficient for effective relief of menopausal symptoms 5
• In postmenopausal women, estradiol levels typically fall significantly, which contributes to various symptoms including vasomotor instability, sleep disturbances, and accelerated bone density loss 5

Conversion Factor

For reference, the conversion between pg/mL and pmol/L for estradiol is:

• 1 pg/mL = 3.671 pmol/L
• 1 pmol/L = 0.272 pg/mL

Understanding these normal ranges is essential for proper interpretation of laboratory results and clinical decision-making in women's health.