Menstruation - Overview

Overview

Regular menstruation (also called eumenorrhea) lasts for a few days, usually 3 to 5 days, but anywhere from 2 to 8 days is considered normal. The average menstrual cycle is 28 days long from the first day of one menstrual period to the first day of the next. A normal menstrual cycle is typically between 21 and 35 days between menstrual periods. The premenstrual time period is termed molimina and symptoms (other than bleeding) preceding menstruation are termed moliminal.

The average volume of menstrual fluid during a monthly menstrual period is 35 milliliters (2.4 tablespoons of menstrual fluid) with 10–80 milliliters (1 - 6 tablespoons of menstrual fluid) considered typical. Menstrual fluid is the correct name for the menstrual flow, although many people prefer to refer to it as menstrual blood. Menstrual fluid in fact contains some blood, as well as cervical mucus, vaginal secretions, and endometrial tissue. Menstrual fluid is reddish-brown, a slightly darker colour than blood.

Many women also notice blood clots or shedding of their uterus's endometrium lining during menstruation. These appear as small pieces of tissue mixed with the blood. Pieces of endometrial tissue are easy to confuse with menstrual clots and a specimen test can confirm which you have. Sometimes menstrual clots or shed endometrial tissue is incorrectly thought to indicate an early-term miscarriage of an embryo. An enzyme called plasmin — contained in the endometrium – tends to inhibit the blood from clotting.

The amount of iron lost via menstrual fluid is relatively insignificant for most women. In one study, premenopausal women who exhibited symptoms of iron deficiency were given endoscopies. 86% of them actually had gastrointestinal disease and were at risk of being misdiagnosed simply because they were menstruating.

The first experience of a menstrual period during puberty is called menarche. The average age of menarche is 13, but menarche can typically occur between ages 8 and 18.Premature or delayed menarche should be investigated, ie before 10 yrs or after 16 years. Perimenopause is when fertility in a female declines, and menstruation may occur infrequently in the years leading up to menopause, when a female stops menstruating completely and is no longer fertile. Menopause typically occurs between the late 40s and 50s in Western countries.