Ultrasound during pregnancy means: Ultrasound in pregnancy: Ultrasound imaging is a technique that has been used during pregnancy for more than three decades. This diagnostic method has been very successful and extremely useful.
(in Medical Dictionary)

What else does Ultrasound during pregnancy mean?

To assess the safety of ultrasound in pregnancy, a number of epidemiological studies have been conducted. This includes studies using a sophisticated research design. No convincing evidence has been provided to support the idea that ultrasounds during pregnancy pose a danger.
(in Medical Dictionary)