Research on the fetus using Doppler ultrasound in the first trimester: guiding ethical considerations

The guiding ethical considerations for fetal research in the United States, reflected in government regulations, are that such research does not involve 'more than minimal risk' and that the pregnant woman provides informed consent for participation. These considerations are not uniquely American. They reflect a cross-cultural concern of obstetricians acting as clinical investigators to protect fetal patients from exposure to unnecessary risks of medical intervention and to respect the rights of pregnant women as research subjects.