"Approximately 7 in 10 women under correctional sanction have minor children & children under the age of 18. An estimated 72% of women on probation, 70% of women held in local jails, 65% of women in State prisons, and 59% of women in Federal prisons have young children.
"Women under correctional care, custody, or supervision with minor children reported an average of 2.11 children of this age. Those on probation reported the fewest, 2.07 young children per woman with children while those in State prison reported an average of 2.38 children under age 18.
"These estimates translate into more than 1.3 million minor children who are the offspring of women under correctional sanction; more than a quarter million of these children have mothers who are serving time in prison or jail. About two-thirds of women in State prisons and half of women in Federal prisons who had young children had lived with those children prior to entering prison."
Greenfield, Lawrence A., and Snell, Tracy L., Bureau of Justice Statistics, Women Offenders (Washington, DC: US Department of Justice, December 1999), pp. 7-8.