3.0-4.4 cm: Micropenis is defined as a normally structured penis that is below the normal size range for an infant. A newborn boy's penis is between 2.8 to 4.2 centimeters with a circumference of 0.9 to 1.3 centimeters .Measurement is done by stretching the penis and measuring from the tip to the base of the penis. At 5 months that range is increased by 0.2 cm
Answered 7/24/2018
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