I am trying to find out what my progesterone level should be to indicate that I am ovulating every month. My level was 10. One reproductive endocrinologist said I was ovulating every month, and another said I was not. Please advise.

-- Peggy

During the first half of the menstrual cycle, called the follicular phase, the egg develops within a fluid-filled sac in the ovary called a follicle. When the egg reaches maturity, the pituitary gland secretes a burst of the hormone LH called the LH-surge. At this point, two things happen. First, the egg is released from the follicle. Next, the walls of the follicle collapse, and the follicle becomes the corpus luteum ("yellow body") of the ovary.

The corpus luteum is responsible for producing progesterone in the second half of the cycle, the luteal phase. In a normal non-stimulated menstrual cycle, a progesterone level above 3-6ng/ml indicates ovulation. It is important to measure the progesterone level early in the morning and while fasting. After meals or later in the day, the level can be significantly lower, causing in a false sense of concern. I feel secure that your cycle is normal with a level of 10ng/ml. For women taking ovulation medications that cause more than one egg to develop, the progesterone level will often be much higher.