All Conditions

Micropenis

A micropenis (mi·​cro·​pe·​nis) is a penis that is smaller than the average size penis.

Overview

What does micropenis mean?

A micropenis occurs when a baby boy is born with a penis that is smaller than average. The normal length of a newborn boy’s penis is 2.8 to 4.2 centimeters (1.1 to 1.6 inches).

  • A baby with a penis that is less than 1.9 centimeters (0.75 inches) long is said to have a micropenis.

  • This condition generally affects the male throughout his life, and can cause problems with sexual function.

Signs and Symptoms

What are the signs and symptoms of a micropenis?

Signs and symptoms include:

  • Smaller than average size penis (0.75 inches or smaller in a newborn, or 2.8 inches or smaller in an adult male)

  • Problems with sexual function

Causes

What are the causes of micropenis?

Micropenis may be caused by hormone defects or deficiencies, or genetics.

Doctors and Providers