MENSTRUAL CYCLE GLOSSARY

Menarche

A girl's first menstrual period.

Menopause

The time in a women's life when menstruation permanently stops. Sometimes referred to as the "change of life". Occurs due to the decrease in production of estrogen and progesterone by the ovaries.

Menorrhagia

Menstrual periods that are abnormally heavy in flow, or that are prolonged and last much longer than usual.

Menses

Another word for menstruation; the menstrual flow.

Derives from the Latin word menses, which means months (singular mensis refers to 1 month).

Note that the word moon, as in the earth's moon which resolves around the earth in approximately 29.5 days, likewise derives from the Latin word mensis.

Menstrual

Adjective; Of or relating to menstruation.

Menstrual Cycle

A recurring cycle that occurs monthly in women as the endometrium (lining of the uterus) thickens and prepares for pregnancy. If the egg released by one of the ovaries at ovulation (which occurs about midway through the cycle) is fertilized as it travels from the fallopian tube to the uterus, pregnancy occurs. If the egg is not fertilized, menstruation occurs: the blood-rich endometrium is shed, and the next month's cycle begins again.

The first day of menstrual blood flow is considered day 1 of the menstrual cycle.

The menstrual cycle is comprised of three phases: the follicular phase, ovulation, and the luteal phase.

Menstrual Cycle Length

This is the number of days from the first day of one menstrual period to the day before the first day of the next menstrual cycle.

Menstruation

The monthly shedding of the endometrium. Menstruation is the part of a woman's menstrual cycle where the endometrium (lining of the uterus) is shed, resulting in discharge of blood. Menstruation occurs each month if the egg released at ovulation is not fertilized. It occurs from menarche during puberty until menopause.

Metrorrhagia

Uterine bleeding that occurs between regular menstrual periods, which usually indicates an underlying medical condition.

Miscarriage

Refers to any spontaneous loss of a pregnancy prior to the 20th week of gestation.

Mittelschmerz

Pain occurring during ovulation on one side of the lower abdomen.

The location of the pain (left or right side) is based on which ovary produces the ovum that menstrual cycle.