Overview
The uterine tubes, also known as oviducts or fallopian tubes, are the female structures that transport the ova from the ovary to the uterus each month. In the presence of sperm and fertilization, the uterine tubes transport the fertilized egg to the uterus for implantation.
Gross anatomy
The uterine tubes are uterine appendages located bilaterally at the superior portion of the uterine cavity. These tubes exit the uterus through an area referred to as the cornua, forming a connection between the endometrial and peritoneal cavities. Each uterine tube is approximately 10 cm in length and 1 cm in diameter and is situated within the mesosalpinx. The mesosalpinx is a fold in the broad ligament. The distal portion of the uterine tube ends in an orientation encircling the ovary. The primary function of the uterine tubes is to transport sperm toward the egg, which is released by the ovary, and to then allow passage of the fertilized egg back to the uterus for implantation.
A uterine tube contains 3 parts. The first segment, closest to the uterus, is called the isthmus. The second segment is the ampulla, which becomes more dilated in diameter and is the most common site for fertilization. The final segment, located farthest from the uterus, is the infundibulum. The infundibulum gives rise to the fimbriae, fingerlike projections that are responsible for picking up the egg released by the ovary.
The arterial supply to the uterine tubes is from branches of the uterine and ovarian arteries; these small vessels are located within the mesosalpinx.
The nerve supply to the uterine tubes is via both sympathetic and parasympathetic fibers. Sensory fibers run from thoracic segments 11-12 (T11-T12) and lumbar segment 1 (L1).
Lymphatic drainage of the uterine tubes is through the iliac and lateral aortic nodes.
Both ultrasonography and hysterosalpingography can be useful in diagnosing uterine anomalies.
Microscopic anatomy
Histologically, the uterine tubes are composed of 3 layers—the mucosa, muscularis, and serosa. The 3 different cell types within the mucosa of the uterine tubes include the columnar ciliated epithelial cells (25%), secretory cells (60%), and narrow peg cells (< 10%).
The mucosa has many folds, called plicae, which are most evident in the ampulla. The next layer is the muscularis, which is a layer of smooth muscle that surrounds the mucosa. The serosa is the outermost layer; it is primarily visceral peritoneum.