A study was carried out between 1987 and 1989 to try to understand why women choose to give their infants up for adoption at birth and the psychodynamics of this decision. The interviews of 22 female subjects were based on psychoanalytic methodology. They revealed that the motives behind such a choice arose from a specific set of symptoms: The denial of pregnancy and fantasies of violence towards the fetus. These symptoms were the result of psychological and sexual traumas that the subjects experienced during their childhood in negligent or incestuous families. Eighteen of the subjects were able to take advantage of the French law permitting anonymous and cost-free delivery, then the adoption of the baby. However, four of the subjects denied their pregnancies so efficiently that childbirth took them by surprise. The sudden discovery of the reality of the newborn led them to neonaticide. This study clarifies the confusion that exists between the abandonment of a child in a public place, and the choice of adoption at birth, the aim of which is to protect the infant from the risk of violence or future neglect.