What is Menstrual Cycle? Menstruation is the part of the
menstrual cycle, the process that helps a woman’s body get ready
for the possibility of pregnancy each month. The average cycle
is 28 days long and starts on the first day of a period. The
menstrual cycle can range from 21 days to 35 days. The brain
pituitary gland, uterus cervix, ovaries, fallopian tubes and
vagina all work together to make the menstrual cycle happen. The
ovaries produce two important hormones, progesterone and
estrogen. The pituitary gland also produces hormones, follicle-
stimulating hormone (FSH) and luteinizing hormone (LH). Girls
usually start menstruating around the age of 13, sometimes even
younger and will continue having monthly periods until the age
of 50 when the process of menopause begins. Menstrual cycles
vary from one woman to the next – some may be short while others
may experience longer cycles. A typical menstrual cycle is 28
days and the length is calculated by counting the first day of
menstruation as day one. Teens