One group will include 20 women under the age 40 years old, with regular menstruation cycles and without any illness or medication including birth control pills or steroidal ointments, and without known diagnosis of polycystic ovaries or fertility disorder. The second group will include 20 women over the age of 60, with no menstruation at least for the last five years, and without hormone therapy or treatment of any Steroidal therapy for the last year.