The Testes

Testes, also known as testicles, are the organs responsible for producing sperm, which are male sex cells necessary for reproduction. Testes are also responsible for producing androgens, which are important for creating and maintaining physical male traits following puberty, and for reproductive activity such as spermatogenesis.1

Typically, males have two testes. The testes are contained within the scrotal sac, located beneath the penis and in front of the anus. They are round in shape and tend to be about the same size as golf balls.

The testes grow in response to the production of sperm, and they typically grow drastically during puberty. Both testes are usually of similar size, but normally one will be slightly larger than the other.

Testes are able to produce sperm at temperatures lower than the core body temperature. This is why testes are located outside of the body, held in place by the spermatic cord that is contained within the scrotum. When testicles become too warm due to warm weather or physical exercise, they descend, which allows for cooling. A healthy scrotum in cool temperatures contains the testes in a tight condition close to the body. 1  

Anatomy of the Testes

Spermatic Cord:  This contains the bundle of nerves, blood vessels, lymphatic vessels and the vas deferens. This cord connects the testicles (testes) to the rest of the body. The spermatic cord also contains the cremasteric muscle, which contracts to pull the testicles closer to the body during cold temperatures and sexual arousal.

Blood Vessels and Nerves: The testes have a high density of nerves on the scrotal skin surrounding them, causing them to be very sensitive.

Vas Deferens: Two separate long, slender tubes that carry sperm up from the epididymis and into the abdominal region of the male human body. The tubes loop around the side of the bladder and terminate near the seminal vesicle. During a vasectomy, each of these tubes is severed to prevent pregnancy.

Epididymis: The epididymis is a single, narrow, tightly-coiled tube connecting the efferent ducts from the rear of each testicle to its vas deferens.1 After being produced in the testicles, sperm are moved to the epididymides, which are located above the testicles. Sperm stay here several weeks, maturing and taking in nutrients.

Seminiferous Tubules: Seminiferous tubules are coiled tubes, the walls of which contain cells that produce sperm. 1Sperm are produced in the lumen, or internal hole, of the seminiferous tubules in a process called spermatogenesis. Special tissue that fills the spaces between the seminiferous tubules, called Leydig cells, produce testosterone.

Injury and Protection

It is well known that the testicles can be very sensitive to injury. Because the testes play such a crucial role in sperm production and male reproductive abilities, they have many nerve endings responsible for alerting the nervous system of possible danger or impact to the testes. In the case of minor injuries to the testes, the pain can travel through the stomach and lower back but will usually subside in a few minutes; however, penetrating or serious injuries to the scrotum can cause castration, which may result in total sterility.

A great way to protect your testicles from injury is to wear a jock strap or hard cup during contact sports, buy a bicycle seat that has a groove or cut-out area to help reduce pressure on the nerves and arteries feeding the penis/testes, and wear a seat belt (as most testicular injuries come from car accidents). 2 

As an Erogenous Zone

The scrotum and testes can be a highly erogenous zone for men. People tend to be nervous touching this area as it is very sensitive, but when touched in the right way it can be very pleasurable for males.

One technique that can be used to stimulate the scrotum is by cupping the scrotum with a hand and gently moving the tips of your fingers. This move can also be very enjoyable when combined with oral sex so the penis and the testes are stimulated simultaneously. 2 Once you are comfortable with fondling this area, licking the area between his testicles can be very arousing (combine this with manual masturbation for more pleasure). The testicles are usually ignored, but they can also be a great erogenous zone for many men, so remember to start off slow, communicate, and enjoy!

Feel free to check out this great video about the testicles!


1. Utiger, M.D. Robert D. "Testis (anatomy)." Encyclopedia Britannica Online. Encyclopedia Britannica, n.d. Web. 26 Feb. 2014.

2. "His Erogenous Zones." His Erogenous Zones. N.p., n.d. Web. 26 Feb. 2014.


Last Updated March 13, 2014