When you can get your hedgehog to uncurl in your hand, you would have to get them to lay flat on their backs.
Males penal sheath, the sex organ, is located about 2/3 down their tummy from their head. It looks much like a large belly button.
A females sex organ is located right next to the anus. If you are unable to get the hedgehog to uncurl in your hand, wait until they uncurl enough to get your hand under their front legs. Then hold them up placing the other hand under their bottom, and then sneak a peak.
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Article By : http://www.pcexotics.org/faqs.htm