Ovaries

The ovaries are almond-shaped, slightly flattened structures. Their size fluctuates, depending on patient age and stage of ovarian cycle. The average size is approximately 2.5 to 5 cm long, 2 cm wide, and 1 cm thick. They are located near the lateral walls of the pelvis. Before pregnancy, the ovaries are approximately at the level of the anterior superior iliac spine lying lateral to the uterus. During pregnancy, however, the uterus rises into the abdomen, pulling the ovaries away from this general location. After pregnancy, they usually assume their original position.

The ovaries are attached to the uterus by the ovarian ligament, which passes from the uterine end of the ovary to the body of the uterus.

The function of the ovaries is to produce the ova and the female sex hormones.

Uterine Tubes

The uterine tubes, or oviducts, provide the path for the ova into the uterus. The spermatozoa travel into the uterine tubes from the uterus after intercourse. Fertilization of the ovum usually occurs in the oviducts.

The oviducts can be subdivided into three parts—the isthmus, ampulla, and infundibulum.¹ The isthmus is thick-walled and narrow and is attached to the uterine wall. The ampulla is the longest and widest part of the oviduct. Its walls are relatively thin. The funnel-shaped infundibulum terminates in finger-like structures called fimbriae. At this point, the oviduct is opened to the peritoneal cavity. There is, however, one finger of the fimbriae that makes a physical connection with the ovary.

Uterus

The uterus is a thick-walled, muscular organ lying within the pelvis. Its position changes with the degree of fullness of the bladder and rectum. It can also be subdivided into several parts—the fundus, body, isthmus, and cervix (Fig. 20-2). The fundus is the rounded upper portion of the uterus. It is found above the line joining the entrance of the uterine tubes. The body of the uterus, a small triangular area between the uterine walls, extends down toward the isthmus. The body is the main portion of the uterus. Between the cervix and the body of the uterus lies the isthmus, a narrow, constricted, very short segment about 1 cm long. The cervix communicates with the vagina, and can be divided into a supravaginal and a vaginal part. The vaginal portion extends into the vagina, whereas the supravaginal part extends up to the isthmus.

Vagina

The vagina is a muscular tube about 3 in (7.6 cm) long that forms the lower portion of the birth canal. The vagina extends upward and posteriorly into the pelvic cavity lying posterior to the urinary bladder. The cervix extends into the upper portion of the vagina, providing a connection between these two structures. The vagina extends from the uterus to the outside of the body and functions to allow intercourse and a path for the fetus to exit the body.