What causes numbness and tinglingi in the private area ?

Many: Have you had any surgeries? It may be related to nerve transection if surgeries in the vicinity were performed.

Genital Numbness: Read this about common causes of numbness: http://www.Rightdiagnosis.Com/sym/groin_numbness.Htm. Are you a bike rider? Wear tight stockings? Diabetic neuropathy is also a common cause, so you should be tested. This definitely warrants contacting your doctor for a thorough evaluation to get to the cause of the problem.