The Sex Organs - The Female Sex Organs

The Internal Sex Organs

The Uterus
Location, form and function
The uterus (lat.: womb) is a muscular organ which is situated between and slightly below the ovaries, approximately in the center of the lower abdomen. The shape of the uterus, which is about 3 inches (ca. 7 cm) long, resembles that of a small pear turned upside down. The Fallopian tubes enter the uterus on either side near the top. The wide upper part, known as the body of the uterus, is usually tilted forward over the dome of the urinary bladder, and it is separated from the narrow lower part by a slight constriction. This lower part is called the cervix or neck of the uterus, and it ends in the deep portion of the vagina. The cervix contains a small opening through which sperm cells can travel from the vagina into the uterus. However, except for a certain period during ovulation, the cervical opening is plugged by an impenetrable mucus.

The three layers of the uterine wall
The thick walls of the uterus are made up of three layers:

1. the external cover called the perimetrium, 2. the middle or muscular layer called the myometrium, and 3. the inner layer called the endometrium.

This endometrium consists of special tissue which thickens every month as the uterus prepares for the possible implantation of a fertilized egg. If no implantation occurs, the endometrium deteriorates and is discharged through the cervix and the vagina during menstruation.

The uterus during pregnancy
In case of a pregnancy, the uterus expands with the growing fetus. The extraordinary muscular structure of the myometrium not only allows for such vast expansion, but also provides the necessary pressure during labor when the fetus is finally expelled. The uterine muscles also contract during orgasm.