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Related to menstruation: Menstruation cycle


periodic flow of blood and cells from the lining of the uterusuterus,
in most female mammals, hollow muscular organ in which the fetus develops and from which it is delivered at the end of pregnancy. The human uterus is pear-shaped and about 3 in. (7.
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 in humans and most other primates, occurring about every 28 days in women. Menstruation commences at puberty (usually between age 10 and 17). The onset of menstruation, called menarche, signals the body's coming readiness for childbearing. It continues, unless interrupted by pregnancypregnancy,
period of time between fertilization of the ovum (conception) and birth, during which mammals carry their developing young in the uterus (see embryo). The average duration of pregnancy in humans is about 280 days, equal to 9 calendar months.
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 until menopausemenopause
or climacteric
, transitional phase in a woman's life when the ovaries stop releasing eggs, ovarian production of estrogen and other hormones tapers off, and menstruation ceases.
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 (around age 50).

There have been many myths and taboos associated with menstruation. Some cultures isolated women or thought the menstrual flow "unclean" or a "curse." More recent taboos against exercise or sexual intercourse during menstruation are slowly lifting. Some scientists have asked why menstruation occurs at all—why the uterine lining does not remain in place, regenerating itself as other parts of the body (such as the skin and digestive tract) do. One theory is that menstruation is a defense against microbes that enter the uterus with incoming sperm.

The Menstrual Cycle

In the first phase of each cycle, the lining, or endometrium, of the uterus undergoes rapid proliferation of cells and venous channels in preparation for pregnancy. Midway through the cycle an ovumovum
, in biology, specialized plant or animal sex cell, also called the egg, or egg cell. It is the female sex cell, or female gamete; the male gamete is the sperm. The study of the ovum is included in the science of embryology.
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 (egg) is released from an ovaryovary,
ductless gland of the female in which the ova (female reproductive cells) are produced. In vertebrate animals the ovary also secretes the sex hormones estrogen and progesterone, which control the development of the sexual organs and the secondary sexual characteristics.
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. If, while passing through the fallopian tubefallopian tube
, either of a pair of tubes extending from the uterus to the paired ovaries in the human female, also called oviducts, technically known as the uterine tube.
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 the ovum is fertilized by a sperm, implantation in the uterus occurs and the thickened lining helps support the pregnancy. When the ovum is not fertilized, this tissue and blood are shed. The proliferation of the uterine wall then begins once more in expectation of the next release of an ovum, and if conception does not take place, it sloughs off again. The process continues monthly until pregnancy occurs or until ovulation ceases at menopause.

The natural rhythm of the menstrual cycle may be broken or temporarily halted by hormonal imbalance, malnutrition, illness, or emotional disturbance (see amenorrheaamenorrhea
, cessation of menstruation. Primary amenorrhea is a delay in or a failure to start menstruation; secondary amenorrhea is an unexpected stop to the menstrual cycle.
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). Menstruation is controlled by the hypothalamushypothalamus
, an important supervisory center in the brain, rich in ganglia, nerve fibers, and synaptic connections. It is composed of several sections called nuclei, each of which controls a specific function.
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 and the pituitary glandpituitary gland,
small oval endocrine gland that lies at the base of the brain. It is sometimes called the master gland of the body because all the other endocrine glands depend on its secretions for stimulation (see endocrine system).
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 and hormones, such as estrogenestrogen
, any one of a group of hormones synthesized by the reproductive organs and adrenal glands in females and, in lesser quantities, in males. The estrogens cause the thickening of the lining of the uterus and vagina in the early phase of the ovulatory, or menstrual, cycle
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, which prepares the lining of the uterus, and progesteroneprogesterone
, female sex hormone that induces secretory changes in the lining of the uterus essential for successful implantation of a fertilized egg. A steroid, progesterone is secreted chiefly by the corpus luteum, a group of cells formed in the ovary after the follicle
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, which helps maintain a pregnancy.

Dysmenorrhea and Premenstrual Syndrome

Many women experience painful menstruation, or dysmenorrhea. The uterine contractions that result in the cramps experienced by these women appear to be caused by hormones called prostaglandins that are produced in the second half of the cycle. Oral contraceptives and other drugs that reduce the production of prostaglandins are sometimes used in treatment. Other women experience symptoms such as behavioral changes, breast tenderness, and fatigue during the week immediately preceding menstruation, a condition referred to as premenstrual syndromepremenstrual syndrome
(PMS), any of various symptoms experienced by women of childbearing age in the days immediately preceding menstruation. It is most common in women in their twenties and thirties.
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, or PMS.


See publications of the National Institute of Child Health and Human Development; Boston Women's Health Book Collective, Our Bodies, Ourselves for the New Century (1998).


Periodic sloughing of the uterine lining in women of reproductive age. Menstrual bleeding indicates the first day of the menstrual cycle, which lasts an average of 27–30 days, although ranges of 21–60 days have been recorded. Menarche, the onset of menstruation, occurs between the ages of 9 and 16. The majority of females begin menstruating at ages 12–14. During the first few years, the duration and intensity of menstrual flow and the total cycle length may be quite variable, but regularity is gradually established. Cessation of menses, or menopause, occurs at an average age of 51, with a range of 42–60 years.

The menstrual cycle consists of cyclic changes in both the ovary and the uterus. These changes are controlled by the interaction of several hormones including follicle-stimulating hormone (FSH) and luteinizing hormone (LH), which are secreted by the anterior pituitary, and the steroid hormones estrogen and progesterone, which are secreted by follicles in the ovary. At the beginning of the cycle, the follicle is stimulated by FSH. In response, it grows and secretes estrogen. The amount of estrogen secretion increases rapidly near the middle of the cycle. Estrogen, in turn, stimulates growth of the uterine lining (mucosa), which becomes thicker and fills with blood vessels. In midcycle, the rapid increase in estrogen causes a massive surge of LH release and a smaller release of FSH from the pituitary. This surge causes ovulation, which is the release of the ovum from the follicle. After ovulation, the follicle undergoes rapid changes and is then called a corpus luteum, which secretes progesterone in response to LH stimulation. Progesterone and estrogen together cause a further thickening of the uterine mucosa, preparing the uterus for pregnancy. If pregnancy does not occur, the corpus luteum degenerates, the uterine mucosa sloughs off, and the cycle begins again.

There is no menstrual bleeding during pregnancy, as the uterine mucosa is needed for the maintenance of pregnancy. This amenorrhea, or lack of normal ovarian function, sometimes continues during nursing.


The periodic discharge of sanguineous fluid and sloughing of the uterine lining in women from puberty to the menopause. Also known as menses.


the approximately monthly discharge of blood and cellular debris from the uterus by nonpregnant women from puberty to the menopause


It is a common dream for women and its interpretation is mostly positive. Dreaming about having your menses can be symbolic of releasing tension and worry. Women are often concerned about their reproductive system. (i. e., pregnancy, sexual relationships or their body’s “time clock” ). Parallel to the menstrual cycle there is a monthly emotional cycle that most women are aware of and experience. During the time of menstruation there is a release of anxiety and an attainment of emotional balance. As a dream symbol it suggests that some difficult times may be over for you and that you can relax. On occasion this dream suggests a loss of energy and disappointment.
References in periodicals archive ?
Each of the many different types of yoga deals with menstruation slightly differently, but most agree that the body's energetic force is downward at this time.
Safe and hygienic menstruation is a basic human right and fundamental to women s equality, said Chris Williams, executive director of WSSCC.
Two days before that and the first day of your menstruation and second day try to avoid any decision.
Despite these flaws in study design, the results demonstrated that chamomile treatment may alleviate general physical and psychological symptoms associated with PMS, and that treatment for approximately 7 days prior to the onset of menstruation was sufficient for benefit, thus not requiring medication for the entire cycle.
I discovered a reverent attitude to menstruation from our tipuna.
The study's authors interpret the results of their research as suggesting that absenteeism due to menstruation does not stem primarily from school environment (e.
But despite the criticism Degtyaryov insisted that the disruption caused by menstruation to working women represents a problem for society and employers.
One girl, upon receiving pads and a health lesson about menstruation and puberty, said, "I would climb a hundred mountains and cross a thousand rivers to get one of those
Keywords: adolescent girls, menstruation and menstrual hygiene, sanitary pads, quality of life, India
The articles analysed in this study showed there to be a growing pocket of biomedics who argue menstruation to be obsolete due to changes in women's life practices and desires, and who subsequently promote the notion of menstrual suppression (Coutinho 1999; Glasier et al.
Menstruation is still regarded as something unclean or dirty in India and the reaction to menstruation depends upon awareness and knowledge about the subject.
Among 12-year-olds (n = 792) who completed a semistructured questionnaire, 363 had achieved menarche and 42% of them reported painful menstruation that correlated with duration of menstrual flow and the amount of blood loss.