Menstruation

The approximately monthly discharge of blood from the womb in women of childbearing age who are not pregnant. Also called menses.

Periodic bleeding as the uterus sheds its lining each month during a woman’s reproductive years. Begins at puberty and ends at menopause.

The cyclic uterine bleeding resulting from degeneration of the endometrium.

Bleeding from the uterus which occurs in a woman each month when the lining of the uterus is shed because no fertilised egg is present.

The periodic drainage of a bloody fluid through the vagina of a woman who is not pregnant; the fluid contains the unused endometrium (lining of the uterus) and the unfertilized egg (ovum). On the average, menstruation occurs approximately once every four weeks, generally every 24 to 35 days, and lasts four to five days, though sometimes it is as short as one day and as long as eight days. For most girls, menarche, the onset of the first menstruation, occurs as part of puberty between ages 10 and 16. It can occur much earlier, as part of what is termed precocious puberty, or somewhat later; but if a girl has not begun menstruating by age 16, parents should probably consult a doctor to see if there is some underlying physical problem. Girls who are overweight tend to begin their periods earlier, while those who are very thin, involved in strenuous physical activity (such as ballet and some sports), or have chronic illness may begin to menstruate later. In recent decades, partly because of improved nutrition, menstruation has tended to start ever earlier.

The periodic drainage of a bloody fluid through the vagina of a woman who is not pregnant; the fluid contains the unused endometrium (lining of the uterus) and the unfertilized egg (ovum). On the average, menstruation occurs approximately once every four weeks, generally every 24 to 35 days, and lasts four to five days, though sometimes it is as short as one day and as long as eight days. For most girls, menarche, the onset of the first menstruation, occurs as part of puberty between ages 10 and 16. It can occur much earlier, as part of what is termed precocious puberty, or somewhat later; but if a girl has not begun menstruating by age 16, parents should probably consult a doctor to see if there is some underlying physical problem (see below). Girls who are overweight tend to begin their periods earlier, while those who are very thin, involved in strenuous physical activity (such as ballet and some sports), or have chronic illness may begin to menstruate later. In recent decades, partly because of improved nutrition, menstruation has tended to start ever earlier.

Discharge of blood and uterine material from the vagina at intervals of about a month during a woman’s reproductive years; also called catamenia.

The monthly discharge of blood and other secretions from a woman’s uterus. Menstruation heralds the beginning of the reproductive years in a woman’s life. Most women have their first period (menarche) around age 12. Menstruation usually stops around age 50 (menopause). The length of the menstrual cycle for most women is 28 days. A woman’s menstrual cycle is the time from the first day of one period to the first day of the next. Normal cycles can vary from 21 to 35 days. The number of days a woman menstruates also may vary. Most women have periods lasting from 3 to 7 days, with an average of about 5 days. Most women have monthly periods; but others have irregular periods. Many different factors can change a woman’s menstrual cycle, including weight gain or loss, an illness, stress, excessive exercise, pregnancy, or menopausal and adolescent transitions.

The discharge of blood and fragments of womb lining from the vagina at intervals of about one month in women of child-bearing age. Menstruation is that stage of the ‘menstrual cycle during which the womb lining, which is thickened in readiness to receive a fertilized egg cell (ovum), is cast off if fertilization does not occur within a limited period of time. The normal duration of discharge varies from three to seven days. In anovular menstruation, discharge takes place without previous release of an egg cell from the ovary. Vicarious menstruation is bleeding from a mucous membrane other than the womb lining when normal menstruation is due.

A periodic change occurring in human females (and the higher apes), consisting chiefly of a flow of blood from the cavity of the womb (UTERUS) and slight constitutional disturbances. It usually begins between the ages of 11 and 15, although its onset may be delayed until as late as 20, or may begin as early as 9 or 10. Along with its first appearance, the body develops secondary sex characteristics: for example, enlargement of the breasts, and axillary and pubic hair.

The cyclic, hormonally generated sloughing of the uterine endometrium, which occurs between puberty and menopause and is accompanied by bloody vaginal discharge. The onset of menstruation (menarche) usually occurs during puberty (9 to 17 years of age). When a woman’s ovum is not fertilized, the corpus luteum undergoes involution, which causes progesterone levels to drop, which in turn triggers menses.

The monthly breakdown and shedding of the lining of the uterus, during which blood and tissue leave the woman’s body through the vagina.

The discharge of blood and tissue from the uterus.

The monthly (approximately) discharge through the vagina of blood, secretions, and tissue debris from the shedding of the endometrium from the nonpregnant uterus.