The uterus has two uterine horns connected by a common uterine body in most animals, but only a uterine body in most primates. Uteri, based on morphology, are of the following types:


Two cervices, no uterine body, and two uterine horns completely separated from each other, in rats, mice, and rabbits.


One cervix, short uterine body, and prominent uterine horns, in swine.


One cervix, prominent uterine body, and two uterine horns, in bitch, cow, goat, ewe, and mare.


One cervix, highly developed uterine body, and no uterine horns, in humans and in nonhuman primates.

Histology of the uterus

The uterus has the following tissue layers from lumen to serosa (Fig. 3):

Endometrium. This layer includes:

Epithelia: simple columnar epithelium, mostly secretory, but with some ciliated cells around the openings of uterine glands. The luminal epithelium lines the uterine lumen and the glandular epithelium forms glands that are highly secretory during the luteal phase of the estrous or menstrual cycle and pregnancy.

Stroma: fibroblasts surrounding basal aspects of luminal and glandular epithelia. Caruncles: specialized aglandular endometrial structures in ruminants for attachment of the placenta.

Myometrium. Inner circular and outer longitudinal layers of smooth muscle.

Perimetrium. Serosa or connective tissue lining the outside of the uterus.

Mesometrium. The portion of the broad ligament that supports the uterus.

Functions of the uterus

The uterus serves as the:

Site for conceptus (embryo/fetus and associated extra-embryonic placental membranes) development from early cleavage stages, implantation, and placentation to term.

Organ for secretion and/or transport of proteins, lipids, carbohydrates, and ions for histotrophic nutrition of the conceptus.

Site of placental development for hematotrophic nutrition of the fetus through transfer of nutrients to the fetal circulation via the placenta. Transporter of sperm.

Organ for peristalsis for expulsion of the fetus at the end of pregnancy.

Organ for secretion of prostaglandin F2a to induce luteolysis in nonpregnant females.

Low Carb Diets Explained

Low Carb Diets Explained

You can burn stored body fat for energy and shed excess weight by reducing the carbohydrate intake in your diet. Learn All About The Real Benefits of Low Carb Diets And Discover What They Can Really Do To Improve The Quality Of Your Life Today.

Get My Free Ebook

Post a comment