Sociologist S. Philip Morgan has compiled Census data on White American women born in the 1860s. Census data tends to over-report childlessness--some women may not report children who died young or who were born out of marriage. Still, this chart shows that many women of childbearing age avoided having children at the turn of the century, even within marriage.
Childlessness was particularly common in New England; over 30% of women went without children in New Hampshire and Massachusetts.
S. Philip Morgan, "Late Nineteenth- and Early Twentieth-Century Childlessness," American Journal of Sociology 97, no. 3 (November 1991), 785.