A woman who experiences variations of less than eight days between her longest cycles and shortest cycles is considered to have regular menstrual cycles. It is unusual for a woman to experience cycle length variations of less than four days.
Length variation between eight and 20 days is considered moderately irregular. Variation of 21 days or more between a woman's shortest and longest cycle lengths is considered very irregular. In the menstrual cycle, changes occur in the female reproductive system as well as other systems like breast tenderness or mood changes. A woman's first menstruation is termed menarche, and occurs typically around age 12. The end of a woman's reproductive phase is called the menopause, which commonly occurs somewhere between the ages of 45 and 55. The menarche is one of the later stages of puberty in girls.
The mean age of menarche in women is 12 years, but is normal anywhere between ages 8 and 16. Factors such as hereditary, diet and overall health can accelerate or delay menarche. The cessation of menstrual cycles at the end of a woman's reproductive period is termed menopause.
The average age of menopause in women is 50 years, with anywhere between 40 and 58 being common. Menopause before age 35 is considered premature. The age of menopause is largely a result of genetics but in some cases illnesses, certain surgeries, or medical treatments may cause menopause to occur earlier.
The menstrual cycle is controlled by endocrine system, is necessary for reproduction. There are three distinct phases:
Menstrual phase starts on1st day and ends on 4th day
Ovulation demarcates the transition from the follicular phase to the luteal phase. The length of each phase varies but the average menstrual cycle is of 28 days. Hormonal contraception changes the normal cycles as it leads to hormonal changes which finally result in preventing reproduction. Follicles develop in the ovary of the females influenced by hormonal levels.