The cervix is the lower part of the uterus that opens into the vagina. It is also called the neck of the uterus.
The endometrium is the mucous membrane that lines the inside of the uterus. The endometrium changes throughout the menstrual cycle. About once a month, it thickens with extra blood vessels. A pregnancy can occur if a fertilized egg attaches to, or implants in, the endometrium. If a pregnancy doesn't occur, part of the endometrium is shed, causing menstrual bleeding.
Current as of: November 22, 2021
Author: Healthwise Staff Medical Review: Sarah Marshall MD - Family Medicine Martin J. Gabica MD - Family Medicine Kathleen Romito MD - Family Medicine JoLynn Montgomery PA - Family Medicine
Medical Review:Sarah Marshall MD - Family Medicine & Martin J. Gabica MD - Family Medicine & Kathleen Romito MD - Family Medicine & JoLynn Montgomery PA - Family Medicine