Prenatal health care beyond the obstetrics service: utilization and predictors of unscheduled care
Magriples U, Kershaw TS, Rising SS, Massey Z, Ickovics JR: Prenatal health care beyond the obstetrics service: utilization and predictors of unscheduled care. Am J Obstet Gynecol. 2008 Jan. PMID: 18166312