A hormone produced in the brain by the pituitary gland, Follicle Stimulating Hormone (FSH) stimulates development of your antral follicles (hence its name). FSH is determined through a blood test that is performed on the second or third day of your menstrual cycle. We always test the level of another hormone, Estradiol, to tell us if the reading is accurate.
How it helps: The FSH levels at the beginning of a menstrual cycle tell us how hard your body is working to send signals to your ovaries. When levels are high, it suggests that the ovaries are not responding well to the pituitary gland’s signals sent from the brain. This is sometimes called diminished ovarian reserve (although a better description might be “diminished ovarian responsiveness”).