To examine the effect that the introduction of new diagnostic technology in obstetric care has had on fetal death.
The Medical Birth Registry of Norway provided detailed medical information for approximately 1.2 million deliveries from 1967 to 1995. Information about diagnostic technology was collected directly from the maternity units, using a questionnaire.
The data were analyzed using a hospital fixed‐effects regression with fetal mortality as the outcome measure. The key independent variables were the introduction of ultrasound and electronic fetal monitoring at each maternity ward. Hospital‐specific trends and risk factors of the mother were included as control variables. The richness of the data allowed us to perform several robustness tests.
The introduction of ultrasound caused a significant drop in fetal mortality rate, while the introduction of electronic fetal monitoring had no effect on the rate. In the population as a whole, ultrasound contributed to a reduction in fetal deaths of nearly 20 percent. For post‐term deliveries, the reduction was well over 50 percent.
The introduction of ultrasound made a major contribution to the decline in fetal mortality at the end of the last century.