Pregnancy and the responsibilities of caring for children create additional barriers for low-income women and families seeking adequate and affordable housing, yet few studies have assessed the relative risk or prevalence of homelessness among pregnant or parenting women in the United States.1 The economic, social, and psychological dislocations associated with housing instability and homelessness may have particularly serious negative consequences for the health and well-being of pregnant and parenting women and their children,2–4 highlighting the need to document the number of women exposed to such conditions. Enumerating homeless populations is fraught with both difficulty and controversy5; however, effective public health planning and advocacy are problematic in the absence of a better understanding of the scope of the homelessness problem among pregnant and parenting women. In light of the need for relevant data, we sought to estimate the prevalence of homelessness among childbearing women living in a single, large urban area within the continental United States. (Authors)