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    Menstrual Cycle

    Menstrual Cycle

    Menstrual cycle: Lining of uterus thickens and egg is released

    During the follicular phase of the menstrual cycle, the lining of the uterus thickens to prepare for pregnancy. An egg becomes ready to be released inside a sac (follicle) on the surface of an ovary. During the luteal phase, the egg is released (ovulation). If the egg is fertilized by sperm, it may attach to (implant in) the lining of the uterus, and pregnancy begins. If the egg is not fertilized or does not implant, the lining of the uterus is shed as blood during the menstrual period (below), and the cycle starts over.

    Menstrual cycle: Uterine lining is shed
    By Healthwise Staff
    Sarah Marshall, MD - Family Medicine
    Kirtly Jones, MD - Obstetrics and Gynecology
    Last Revised July 23, 2012

    Last Revised: July 23, 2012

    Author: Healthwise Staff

    Medical Review: Sarah Marshall, MD - Family Medicine & Kirtly Jones, MD - Obstetrics and Gynecology

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