Progesterone levels vary depending on the time of the menstrual cycle, the trimester of pregnancy, and whether or not one is menstruating or is male. Progesterone levels are measured in nanograms per milliliter (ng/mL) or nanomoles per liter (nmol/L). Below are the normal ranges for progesterone levels:

• Prepubescent girls: 0.1-0.3 ng/mL
• Menstruating females:
  • Day 1-14 during the menstrual cycle: <1 ng/mL or 0.5-2.3 nmol/L
  • Day 15-29 during the cycle: 2-25 ng/mL or 6.4-79.5 nmol/L
• Postmenopausal women: <1 ng/mL or <2 nmol/L
• Pregnant women (trimester):
  • 1st trimester: 10-44 ng/mL or 32.6-140 nmol/L
  • 2nd trimester: 19.5-82.5 ng/mL or 62-262 nmol/L
  • 3rd trimester: 65-290 ng/mL or 206.7-728 nmol/L
• Men: <1 ng/mL or <3.2 nmol/L

It is important to note that normal ranges can vary between laboratories, and results should be interpreted by a healthcare provider. Additionally, progesterone levels can fluctuate depending on a variety of factors, including frequency of ovulation, stage of menopause, and use of birth control medications.