Refers to, menstruation, the monthly hormonal cycle that results in shedding of the lining of the uterus.
Normally 28 days (+ or – 7 days), a duration of flow of 4 days (+ or – 2 days) and a blood loss of 40 mL (+ or – 20 mL).
Whole blood constitutes 30-50% of total flow in most women with the extra fluid endometrial transudate, tissue fragments and endometrial debris.
Duration of bleeding maybe up to eight days.
Regular menstrual bleeding should be nine days or less in variation from the beginning of one menses to the beginning of the next one.
Variation in menstrual bleeding is age-dependent so that women between ages 26 and 41 years should have variation of seven days or less in menstrual cycle length.
Amenorrhea is when menses or absent or a woman experiences no bleeding.
Frequent menstrual bleeding is when menses occurs less than 24 days apart, and infrequent is when menses occur ore than 30 days apart.
There is little or no correlation with self-assessment of blood loss and actual measured blood loss.
A Swedish study indicated that the average blood loss per menstrual cycle is about 30 mL, it is more than 85 mL in 10% and greater than 118 mL in 5% of women (Hallberg L).
Women determine menstrual volume to be heavy, normal, or light.
Heavy menstrual bleeding is defined as excessive menstrual blood loss that interferes with physical, social, emotional, or material quality of life.
Intermenstrual bleeding is bleeding between spontaneous, predictable menses and may occur randomly through the cycle or predictably and cyclically in early, mid, or late cycle.
Breakthrough bleeding may occur on hormone medications such as birth control pills/patches/rings or progesterone only contraceptives.
Physical examination that includes speculum and bimanual examinations, with or without rectal exam can help isolate the cause of bleeding to the uterus rather than to the vulvar, vaginal, cervical, or rectal sources.
Amount of loss per individual period tends to recur with each cycle.
Typical cycle has two phases: a proliferative and a secretory phase.
Proliferative phase is characterized by a predominance of estrogen and endometrial buildup.
Secretory phase begins following ovulation and triggers progesterone production.
Secretory phase stabilizes endometrial thickness and is a reaction to a combination of estrogen and progesterone.
When estrogen and progesterone levels taper off menstrual bleeding occurs.
In general oral contraceptives decrease and intrauterine devices increase the amount of menstrual blood loss.
In the absence of ovulation progesterone levels do not rise and typical withdrawal of estrogen and progesterone cannot occur.
Menstruation is a potent migraine trigger.
Tranexamic acid appears to improve quality of life for adolescents with heavy menstrual bleeding.