The Mullerian duct is a duct, or tube, that is present in the human embryo. This duct extends down the sides of the structure known as the urogenital ridge, a structure that later develops to help form the external genitalia, and ends at the Mullerian eminence, a structure that helps form the urinary and genital organs. It is interesting to note that the Mullerian duct only develops fully in females, helping to form the female reproductive system. If the embryo becomes male, these ducts are lost.
While the female embryo is in the developmental stages, there are two separate structures that will develop to assist one another with the formation of the reproductive system. One of these structures is the Mullerian duct itself, and the other is called the urogenital sinus. The urogenital sinus eventually evolves into the bladder as well as helping to form other parts of the urinary and reproductive systems.
The Mullerian duct is present in the embryo of both genders. In females, this pair of ducts will develop into the organs of reproduction. In males, these ducts will disappear. However, the adjoining ducts, known as the Wolffian ducts, will develop and help to form the male reproductive organs.
A chemical known as the anti-Müllerian hormone controls the development of the Mullerian duct by the very presence or absence of this hormone, which is made primarily in the testicles of male embryos. Disturbances in the production of this hormone, and consequently the Mullerian duct, can lead to medical issues, depending on the nature of the disturbance.
Persistent Müllerian duct syndrome is a condition in which the Mullerian duct does not disappear in the male embryo. Instead, a uterus or other derivative of this duct is present. In humans, the most common cause of this syndrome is a genetic disorder or mutation. Surgery to remove the female organs or tissues is generally performed in the hopes of preserving male reproductive capabilities.
Müllerian agenesis is another medical condition that can occur due to abnormalities in the hormones responsible for the development of the Mullerian duct. With this condition, the uterus is missing in the female, and there are usually various types of malformations of the vagina. Surgery is an option in order to allow for comfortable sexual intercourse. However, there is currently no way to allow for fertility in the female with this condition. Counseling is often suggested to those suffering from this disorder.
