Jump to navigation Jump to search
Menstrual cycle.

WikiDoc Resources for Menstruation


Most recent articles on Menstruation

Most cited articles on Menstruation

Review articles on Menstruation

Articles on Menstruation in N Eng J Med, Lancet, BMJ


Powerpoint slides on Menstruation

Images of Menstruation

Photos of Menstruation

Podcasts & MP3s on Menstruation

Videos on Menstruation

Evidence Based Medicine

Cochrane Collaboration on Menstruation

Bandolier on Menstruation

TRIP on Menstruation

Clinical Trials

Ongoing Trials on Menstruation at Clinical

Trial results on Menstruation

Clinical Trials on Menstruation at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Menstruation

NICE Guidance on Menstruation


FDA on Menstruation

CDC on Menstruation


Books on Menstruation


Menstruation in the news

Be alerted to news on Menstruation

News trends on Menstruation


Blogs on Menstruation


Definitions of Menstruation

Patient Resources / Community

Patient resources on Menstruation

Discussion groups on Menstruation

Patient Handouts on Menstruation

Directions to Hospitals Treating Menstruation

Risk calculators and risk factors for Menstruation

Healthcare Provider Resources

Symptoms of Menstruation

Causes & Risk Factors for Menstruation

Diagnostic studies for Menstruation

Treatment of Menstruation

Continuing Medical Education (CME)

CME Programs on Menstruation


Menstruation en Espanol

Menstruation en Francais


Menstruation in the Marketplace

Patents on Menstruation

Experimental / Informatics

List of terms related to Menstruation

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Phone:617-632-7753


Menstruation is a phase of the menstrual cycle in which the uterine lining (endometrium) is shed. Menstrual cycles occur exclusively in humans and other great apes.[1] The females of other mammalian species experience an estrus, in which the endometrium is reabsorbed by the animal at the end of its reproductive cycle.


Eumenorrhea denotes normal, regular menstruation that lasts for a few days (usually 3 to 5 days, but anywhere from 2 to 7 days is considered normal).[2] The average blood loss during menstruation is 35 millilitres with 10-80 mL considered normal;[3] many females also notice shedding of the endometrium lining that appears as tissue mixed with the blood. An enzyme called plasmin — contained in the endometrium — tends to inhibit the blood from clotting. Because of this blood loss, females have higher dietary requirements for iron than do males to prevent iron deficiency. Many females experience uterine cramps, also referred to as dysmenorrhea, during this time. A vast industry has grown to provide drugs to aid in these cramps, as well as sanitary products to help manage menses.

As part of the menstrual cycle

Menstruation is the most visible phase of the menstrual cycle. Menstrual cycles are counted from the first day of menstrual bleeding, because the onset of menstruation corresponds closely with the hormonal cycle.

The evolutionary impetus for menstruation remains somewhat unclear. Most mammals reabsorb the uterine lining during their oestral cycle. The ancient writer Hippocrates considered that menstruation was intended to cleanse the body of "evil humours", and modern evolutionary biologist Margie Profet contends that the primary function of menstruation is to remove sperm-borne pathogens from the uterus. In support of this theory, she has pointed to the relatively high levels of macrophages in menstrual blood. Anthropologist Beverly Strassmann has posited that the energy savings of not having to continuously maintain the uterine lining more than offsets the blood loss of menstruation. Currently, however, no single explanation of the evolutionary purpose of menstruation is accepted.[4]

Beginning in 1971, some research suggested that menstrual cycles of co-habiting human females became synchronized. Anthropologists such as Desmond Morris and Chris Knight hypothesized that in hunter-gatherer societies, males would go on hunting journeys whilst the females of the tribe were menstruating, speculating that the females would not have been as receptive to sexual relations while menstruating.[5][6] However, there is currently significant dispute as to whether menstrual synchrony exists.[7]

Culture and menstruation

Common usage refers to menstruation and menses as a period. Aside from its biological purpose, this bleeding serves as a sign that a woman has not become pregnant. (However, this cannot be taken as certainty, as sometimes there is some bleeding in early pregnancy, and some women have irregular cycles.) During the reproductive years, failure to menstruate may provide the first indication to a woman that she may have become pregnant. A woman might say that her "period is late" when an expected menstruation has not started and she might have become pregnant.

Many religions have menstruation-related traditions. These may be bans on certain actions during menstruation (such as intercourse in orthodox Judaism and Islam), or rituals to be performed at the end of each menses (such as the mikvah in Judaism and the ghusl in Islam). Some traditional societies sequester females in residences ("menstrual huts") that are reserved for that exclusive purpose until the end of their menstrual period.

Physical experience

Template:Seealso In many women, various intense sensations brought about by the involved hormones and by cramping of the uterus can precede or accompany menstruation. Stronger sensations may include significant menstrual pain (dysmenorrhea), abdominal pain, migraine headaches, depression, emotional sensitivity, feeling bloated, and changes in sex drive. Breast discomfort caused by premenstrual water retention or hormone fluctuation is very common. The sensations experienced vary from woman to woman and from cycle to cycle.

Emotional reactions

Many women experience emotional side-effects. These range from the irritability popularly associated with Premenstrual Syndrome, to tiredness, or "weepiness" (i.e. tears of emotional closeness). A similar range of emotional effects and mood swings is associated with pregnancy.


The normal menstrual flow follows a "crescendo-decrescendo" pattern; that is, it starts at a moderate level, increases somewhat, and then slowly tapers. Sudden heavy flows or amounts in excess of 80 mL (hypermenorrhea or menorrhagia) may stem from hormonal disturbance, uterine abnormalities, including uterine leiomyoma or cancer, and other causes. Doctors call the opposite phenomenon, of bleeding very little, hypomenorrhea.


The typical woman bleeds for two to seven days at the beginning of each menstrual cycle. Prolonged bleeding (metrorrhagia, also meno-metrorrhagia) no longer shows a clear interval pattern. Dysfunctional uterine bleeding refers to hormonally caused bleeding abnormalities, typically anovulation. All these bleeding abnormalities need medical attention; they may indicate hormone imbalances, uterine fibroids, or other problems. As pregnant patients may bleed, a pregnancy test forms part of the evaluation of abnormal bleeding.

Menstrual products

Most women use something to absorb or catch their menses. There are a number of different methods available.

Disposable items:

  • Sanitary napkins (Sanitary towels) or pads - Somewhat rectangular pieces of material worn in the underwear to absorb menstrual flow, often with "wings," pieces that fold around the panties, and/or an adhesive backing to hold the pad in place. Disposable synthetic pads are made of wood pulp or synthetic products, usually with a plastic lining and bleached. Some sanitary napkins, particularly older styles, are held in place by a belt-like apparatus, instead of adhesive or wings.
  • Tampons - Disposable cylinders of treated rayon/cotton blends or all-cotton fleece, usually bleached, that are inserted into the vagina to absorb menstrual flow.
  • Padettes - Disposable wads of treated rayon/cotton blend fleece that are placed within the inner labia to absorb menstrual flow.
  • Disposable menstrual cups -- A firm, flexible cup-shaped device worn inside the vagina to catch menstrual flow. Disposable cups are made of soft plastic.

Reusable items:

  • Reusable cloth pads are made of cotton (often organic), terrycloth, or flannel, and may be handsewn (from material or reused old clothes and towels) or storebought.
  • Menstrual cups - A firm, flexible bell-shaped device worn inside the vagina to catch menstrual flow. Reusable versions include rubber or silicone cups.
  • Sea sponges - Natural sponges, worn internally like a tampon to absorb menstrual flow.
  • Padded panties - Reuseable cloth (usually cotton) underwear with extra absorbent layers sewn in to absorb flow. (like Lunapads)
  • Blanket, towel - (also known as a draw sheet) -- large reusable piece of cloth, most often used at night, placed between legs to absorb menstrual flow.

In addition to products to contain the menstrual flow, pharmaceutical companies likewise provide products — commonly non-steroidal anti-inflammatory drugs (NSAIDs) — to relieve menstrual cramps. Some herbs, such as dong quai, raspberry leaf and crampbark, are also claimed to relieve menstrual pain, however there is no documented scientific evidence.[8]


  1. Derry PS (2007). "Is menstruation obsolete?". Br Med J. 334: 955.
  2. The National Women's Health Information Center (November 2002). "What is a typical menstrual period like?". U.S. Department of Health and Human Services.
  3. David L Healy (2004-11-24). "Menorrhagia Heavy Periods - Current Issues". Monash University. ABN 12 377 614 012.
  4. Template:Cite paper
  5. Template:Cite paper
  6. Chris Knight (1991). Blood relations: menstruation and the origins of culture. New Haven, Conn: Yale University Press. ISBN 0-300-06308-3.
  7. Adams, Cecil. "Does menstrual synchrony really exist?". The Straight Dope. The Chicago Reader.
  8. "Herbs For Premenstrual Syndrome". 2004.

See also

Further reading

Template:Reproductive physiology

bg:Менструация cs:Menstruace da:Menstruation de:Menstruation eo:MenstruoTemplate:Link FA fi:Kuukautiskierto gl:Menstruación he:וסת hr:Menstruacija id:Menstruasi it:Mestruazione lt:Menstruacija nl:Menstruatie no:Menstruasjon simple:Menstruation sr:Менструација su:Kareseban

Template:WikiDoc Sources