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Should the definition of micropenis vary according to ethnicity?
1Endocrinology and Diabetes Unit, British Columbia's Children's Hospital, University of British Columbia, Vancouver, B.C., Canada.
Objective:
We determined whether the existing reference values for the diagnosis of micropenis are appropriate for optimal care of neonates in a multiethnic environment like Vancouver.
Methods:
The stretched penile length and width were measured in 105 full-term newborn males of Caucasian (n = 40), Chinese (n = 40) and East-Indian origin (n = 25).
Results:
Mean length -2.5 SD was used for the definition of micropenis and was 2.6, 2.5 and 2.3 cm for Caucasian, East-Indian and Chinese babies, respectively (p < 0.05). This is close to the widely accepted recommendation that a penile length of 2.4- 2.5 cm be considered as the lowest limit for the definition of micropenis.
Conclusion:
Mean penile length and diameter are slightly but significantly smaller in newborns of Chinese origin compared to newborns of Caucasian and East-Indian origins.
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