Recently, professionals in France have noticed an increase in newborns with Down syndrome (DS) being placed for adoption. The aim of this study was to investigate DS babies given up at birth for adoption and to consider the possible determinants of this in order to assess social acceptance of DS. A retrospective cohort of all living DS babies was collected from two birth-defect registries (Paris: 1981-1990; Marseilles area: 1984-1990). Follow-up data were collected: characteristics of the baby, biological parents and maternity units, age when given up for adoption, and type of foster care. The results showed that 19.4 per cent of infants with DS (115/593) were rejected by their parents. Multiple regression analysis indicated that foreign origin of the mother, area of residence, no associated major malformation, maternal age (15-24 years), and birth rank (> 2) variables were significantly associated with a lower placement rate. Among the 115 abandoned infants with DS, 88 came from unknown parentage (76.5 per cent). For half of them, adoptive placement (88/115) occurred before the age of 6 months. Socio-cultural attitudes play a great part in these family decisions. Equally important is the manner in which professionals propose adoption as an alternative to these parents of DS babies. They should be encouraged to consider all options before making a decision, so that the best solution can be found for the interest of all.