menstrual cycle

Scientific  

/ mĕn′stro̅o̅-əl /

1. The recurring monthly series of physiological changes in women and other female primates in which an egg is produced in the process known as ovulation, and the uterine lining thickens to allow for implantation if fertilization occurs. If the egg is not fertilized, the lining of the uterus breaks down and is discharged during menstruation.

2. See also ovulation menstruation

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menstrual cycle Cultural  

1. The periodic series of changes in the female reproductive system associated with the preparation of the uterus for pregnancy; the cycle is repeated roughly every twenty-eight days. During the menstrual cycle, an ovum is released from one of the ovaries (the release is called ovulation), and the uterus develops an inner lining enriched with blood to prepare it for the possible implantation of a zygote. If fertilization and implantation do not take place, the lining of the uterus is discharged during menstruation.

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Example Sentences

Activated by the hormones of the menstrual cycle, these sores thicken and bleed each month, inflaming and scarring the surrounding tissue.

From BBC • Jun. 1, 2026

Blackburn has adenomyosis, endometriosis and fibromyalgia and said she plans her life around her menstrual cycle.

From BBC • May 20, 2026

In addition to leading Evie, they also run the period-tracking app 28, which makes fitness recommendations based on the phase of a woman’s menstrual cycle.

From The Wall Street Journal • Feb. 18, 2026

In January, a cycle coach joins the team to lead workshops on syncing not just workouts but nutrition, creativity — even finances — to the menstrual cycle.

From Los Angeles Times • Jan. 14, 2026

She also made note of her menstrual cycle.

From "Charles and Emma: The Darwins' Leap of Faith" by Deborah Heiligman