What are normal hormone levels for women, and how do you get them tested?

Hormone levels in women depend strongly on age and phase of the menstrual cycle, which means there is no universal 'normal'. LH, FSH, estradiol and progesterone all fluctuate from one day of the cycle to the next. Reference values are only meaningful when they are linked to a specific cycle phase, preferably around the time of ovulation. If you want your cycle hormones tested, discuss with your doctor in advance which day of the cycle the blood draw should be scheduled.

AMH (anti-Mullerian hormone) is the hormone that best indicates how many eggs you still have in reserve. This hormone declines steadily from your twenties onward and the decline accelerates toward forty. Reference values differ considerably by age group: a value of 1 to nearly 10 ng/ml is normal for women aged 20-24, whereas for women aged 48-49 a value as low as 0.01 ng/ml can already be normal. AMH can be measured at any point in the cycle, which makes it a practical measurement.

FSH rises only late in the lead-up to menopause; inhibin B declines earlier, and estradiol does not fall noticeably until roughly two years before the final menstrual period. A single FSH measurement therefore says little about menopausal status, given the large day-to-day variation.

Testosterone in women is a complicated matter. Normal values are poorly defined and vary considerably between laboratories and measurement methods. The most reliable measurement is free testosterone using a specialized technique (equilibrium dialysis), but in practice calculated free testosterone, based on total testosterone plus SHBG (the transport protein that binds testosterone), is a good alternative. The commonly used rapid tests for free testosterone from a fingerprick or direct immunoassay are less reliable. Furthermore, testosterone in women barely declines during menopause itself; symptoms such as reduced libido in that phase are more often linked to the fall in estradiol. Harmonized reference values for testosterone in women do not yet exist: an international process to develop them is under way, but has not yet been completed.

If you want your hormones tested, the first step is a conversation with your general practitioner or gynecologist, who can determine which hormones are worth measuring and at what point in time. Always ask about cycle day, your age, and the measurement method, because these factors determine how the result should be interpreted.