Pain During Menstrual Periods Anatomy
To better understand painful menstrual periods, it helps to understand the anatomy of the uterus, cervix, and Fallopian tubes.
The female reproductive organs include the vagina, cervix, uterus, fallopian tubes and ovaries. The lining of the uterus is called the endometrium.
Before ovulation, the endometrium grows and becomes thick: the endometrial tissue and blood vessels support a fertilized egg when it enters the uterus.
If an egg is not fertilized, it does not attach to the endometrium and the endometrium breaks down. The uterus sheds the endometrium, which causes the bleeding associated with the menstrual period.
The uterus is composed of smooth muscle. During the normal menstrual cycle the uterus will undergo successive periods of contraction followed by relaxation. At times the contractions are more pronounced, and can cause discomfort.
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