Estradiol is the primary type of estrogen produced by the ovaries. During the reproductive years, levels of estradiol rise and fall with the menstrual cycle, reaching a peak just before ovulation.
In perimenopause, the transition phase leading to menopause, estradiol levels typically become more variable. As ovarian function begins to decline, the levels can fluctuate wildly. This can result in periods of both high and low estrogen levels.
While estradiol levels can range widely in perimenopause, generally they start to decrease. Normal estradiol levels for premenopausal women can range from about 15 to 350 picograms per milliliter (pg/mL), depending on the point in the menstrual cycle. In perimenopause, these levels can still be within this range, but tend to trend toward the lower end and can be quite irregular.
In the later stages of perimenopause and into menopause, estradiol levels typically drop further, often falling below 30 pg/mL. However, these values can differ significantly among individuals, and a healthcare provider should be consulted for personal medical advice.
Just as with Follicle Stimulating Hormone (FSH) levels, the diagnosis of perimenopause is typically based on more than just hormone levels. Other factors, including age, menstrual irregularities, and symptoms such as hot flashes, are considered as well. Always consult a healthcare provider for concerns regarding perimenopause and menopause.