From the Research
To monitor estrogen levels, the most common lab tests include serum estradiol (E2), which measures the primary circulating estrogen, and should be maintained between 40-100 pg/mL for postmenopausal women on hormone replacement therapy, as evidenced by the study published in 2021 1.
Key Considerations
- The primary circulating estrogen is measured by serum estradiol (E2) levels.
- For postmenopausal women on hormone replacement therapy, estradiol levels should typically be maintained between 40-100 pg/mL.
- Testing should be done at trough levels (just before the next dose) for the most accurate results.
- Additional relevant tests include follicle-stimulating hormone (FSH), luteinizing hormone (LH), and sex hormone-binding globulin (SHBG) to evaluate overall hormonal balance and the body's response to estrogen therapy.
Monitoring and Maintenance
- Regular monitoring every 3-6 months during dose adjustments and annually thereafter is recommended to ensure safety and efficacy of treatment.
- The use of sensitive and specific assays, such as LC-MS/MS methods, to monitor estrogen levels during AI treatment is essential to minimize the risk of a proceeding inefficient endocrine therapy, as noted in the study published in 2021 2.
Factors Affecting Serum Estradiol Levels
- Higher body mass index (BMI), higher weight, surgical menopause, alcohol use, and antihypertensive medication use are associated with higher serum estradiol levels, whereas current and past smoking are associated with lower serum estradiol levels, as found in the study published in 2020 3.
- Estradiol dose and serum estradiol levels have a differential effect on metabolic measures among early compared to late postmenopausal women, as reported in the study published in 2020 4.