"In common with the rest of Graeco-Roman society Christians married and bore children. Unlike their culture, however, they utterly refused to engage in the practice of child exposure: "They marry and beget children, though they do not expose their infants" (Letter to Diognetus, 2nd Century). This practice of placing unwanted babies out in the streets or on the edge of town near the garbage dumps was all too common throughout the Graeco-Roman world. The wealthy did not want to share their worldly wealth among too many heirs; the poor had too many mouths to feed. A frank statement of this practice has been found recently in a letter written around the year 1 BC by a man who was away on a business trip. He instructed his pregnant wife in Alexandria, who was about to give birth, "When you give birth, if it is male leave it, if a female, cast it out."
Rediscovering the Church Fathers, p. 63
The refusal of the early Christians to participate in such a practice was one of the things which separated them from the pagan culture around them.