menstrual cycle
Meaning of menstrual cycle: The menstrual cycle is the recurring hormonal sequence that prepares the uterine lining for pregnancy and sheds it when pregnancy does not occur.
Definition of menstrual cycle
The menstrual cycle is the recurring sequence of hormonal changes that begins with the onset of one menstrual period and continues until the beginning of the next. It is regulated by a coordinated signaling system involving the brain and the ovaries, and its overall length can vary somewhat from one person to another and from cycle to cycle.
The cycle is generally divided into phases. During the first phase, the ovary develops a follicle while rising estrogen prepares the uterine lining to thicken, followed by ovulation, the release of an egg from the ovary. In the phase that follows, progesterone rises to further prepare the uterine lining to support a possible pregnancy.
If pregnancy does not occur, hormone levels fall, and the thickened uterine lining is shed as menstrual bleeding, marking the start of the next cycle. Irregularities in this pattern can result from a range of hormonal, structural, or other underlying causes.
Used in a sentence
The patient's menstrual cycle history was reviewed as part of the gynecologic evaluation.
Good to know
A menstrual cycle length that varies somewhat from month to month is common and expected, whereas a pattern of persistent absence or marked irregularity is generally what prompts further evaluation.
Word origin
Where “menstrual cycle” comes from
Formed from Latin mensis, meaning month, and Greek kyklos, meaning circle.