The 1991 Longitudinal Follow-up to the 1988 National Maternal and Infant Health Survey (NMIHS) was conducted by the National Center for Health Statistics. The 1991 Follow-up study examines such factors as child health status and development, the effects of low birth weight, use of federal programs, child safety, child injury, child care, pediatric care, maternal health, sociodemographic characteristics, acute and chronic illness, and health insurance. The 1988 study examined factors relating to poor pregnancy outcome, such as adequacy of prenatal care, inadequate or excessive weight gain during pregnancy, maternal health behaviors such as smoking, drinking and drug use, and pregnancy and delivery complications. The 1988 National Maternal and Infant Health Survey (NMIHS) is archived as RADIUS dataset #18-20.

This dataset includes data for the 1991 Follow-up Live Birth Survey and the 1991 Follow-up Medical Provider Survey. The 1991 Follow-up Live Birth Survey includes 722 variables and 8,285 cases. The 1991 Follow-up Medical Provider Survey includes 217 variables and 99,117 medical provider contacts. Because the Provider file contains hierarchical data, the Live Birth and Provider files were not merged to create a single dataset. Live Birth and Provider files have been archived as separate datasets, RADIUS datasets #01 and #02, respectively.