[The difference in mortality between biological children and foster children: the example of Druillat (Ain) in the seventeenth century].

Druillat, a parish in Bresse, welcomed a lot of abandoned infants who had been found a foster home by Lyons Hôtel-Dieu (hospital) during the second half of the eighteenth century. After specifying the annual volume of this incoming flow, the arrival of each infant at its foster home is considered. The notion of foster home covers in diversified family situations as far as the number of native children and infants are concerned. Through the comparison of deaths recorded locally and the Hôtel-Dieu register keeping lists of the infants' placements, the mortality of foster infants can be precise and compared to that of natives. The age at which they were put out to nurses and the host family standards of living, plays a fundamental role as far as the infant mortality risks are concerned.