To better understand premenstrual syndrome, it may help to understand the anatomy of the uterus, cervix, and Fallopian tubes, and how they are affected by menstruation.
The female reproductive organs include the vagina, cervix, uterus, fallopian tubes and ovaries. The lining of the uterus is called the endometrium.
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.
Anatomy of the female reproductive tract includes:
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