This contract will provide data on all births of D.C. residents for the period of June 15, 1987 to June 14, 1991. The information will be provided on tapes and will represent copies of the complete vital data reporting of births of D.C. residents during that period of time. In addition, the vital records of participants in the Better Babies project during that period of time who have provided informed consent for the release of this information will be identified separately. These data will be used to monitor the impact of the Better Babies Project on the target population and to contrast changes in the target population and in rate of low birth weight with that of comparable areas of Washington, D.C. during that period of time.