Pilot test of prenatal surveillance for birth defects in South Texas

The Texas Birth Defects Registry (TBDR) does not access prenatal diagnostic facilities to ascertain cases. Objectives of the study were to determine how many cases may be missing from the registry as a result, and to assess the feasibility and utility of prenatal surveillance for birth defects, through a pilot test in one region of Texas.

A trained abstractor reviewed medical records of all patients with abnormal ultrasound findings during 2004 in all prenatal diagnostic facilities in Texas Health Region 11 (n = 6 facilities). When birth defects were prenatally detected, demographic and diagnostic data were abstracted. Prenatal abstractions were matched to cases in the TBDR. Those that did not match to registry cases were matched to vital records to determine where and when the pregnancy ended; delivery hospital medical records were reviewed for these cases.

Approximately 760 patient charts were reviewed at prenatal diagnostic facilities and 365 were abstracted. Of these, 165 (45%) matched to cases in the TBDR. Delivery medical records were located and reviewed for 177 prenatal abstractions, with 170 (47%) indicating at delivery no defects monitored by the registry. Delivery records for one (0.3%) prenatal abstraction were not found by the hospital. Date and place of delivery were unknown for 22 (6%) prenatal abstractions. Only eight additional infants and fetuses (one twin pair) eligible for the registry were identified.

For Texas Health Service Region 11, it is not necessary to conduct surveillance in prenatal diagnostic facilities, and to do so would be very labor-intensive.