menstruation

menstruation

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

Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

Menstruation

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.

McGraw-Hill Concise Encyclopedia of Bioscience. © 2002 by The McGraw-Hill Companies, Inc.

menstruation

[‚men·strə′wā·shən]

(physiology)

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

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

Menstruation

(dreams)

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.

Bedside Dream Dictionary by Silvana Amar Copyright © 2007 by Skyhorse Publishing, Inc.