Sex assignment refers to the assigning of sex at the birth of a baby. In over 99.9 percent of births, a relative, midwife, or physician inspects the genitalia when the baby is delivered, sees ordinary male or female genitalia, and declares, "it's a girl" or "it's a boy" without hesitation or uncertainty. The assignment is perceived as a recognition of an essential aspect of this new human being, apparent to everyone. In nearly all cases, usually without conscious deliberation, the parents rear the child as a member of the assigned sex/gender.