Menstruation is an indication of the maturity of a girl; the start of menstruation is often a signal that the girl is becoming ready for pregnancy. The menstruation age varies; some girl may start menstruating at the age of 8 years while for some girls it begins at the age of 16. But normally the age 12 is considered to be the average age of menstruation. The menstruation period time lasts up to the start of menopause which is generally 51. During the menstruation period time many physical as well as psychological changes occur in women.

Though the menstrual period lasts for two to seven days but generally three to five days is considered to be more common.  The menstruation cycle is generally 28 days long but depending on the age and body conditioning it may vary from 23 days to 35 days.

Menstruation period time has several phases; these phases are menstrual phase, luteal phase, follicular phase and ischemic phase. Menstruation is accompanied by bleeding; it is an indication that pregnancy has not occurred.  However, during early stages of pregnancy bleeding might occur. Follicle stimulating hormone which is responsible for the production of estradiol and estrogen plays a significant role during these 28 days of menstruation cycle. The egg gets matured and causes the release of luteinizing hormone.  This may cause mild pain and bleeding in women.

Estrogen and progesterone-the two sex hormones plays a very vital role in menstruation period time. Estrogen is highly active during the luteal phase and during the follicular growth. Progesterone plays a significant role during the pregnancy and also during the luteal phase.

Normal menstrual period time may vary from person to person-however it is better to see a doctor if you are experiencing acute physical or mental changes during the periods.