Definition: Legitimate birth
The birth of a child to a mother who, according to national law or customs, was married at the time of the birth.
This term should not be used to explicitly describe the child on the birth certificate unless specifically required by national law, but rather may be considered as a statistical term for counting such births to describe the number of in-wedlock and out-of-wedlock births which have occurred.
United Nations, "Handbook on Training in Civil Registration and Vital Statistics Systems", Studies in Methods, Series F, No. 84, New York, 2002