Sound waves move more easily through liquids than through surrounding tissues and air. Consequently, a full bladder facilitates passage of sound waves through it, making the uterus and ovaries behind the bladder easier to see.

When you eat, drink, or even chew gum, you introduce air into stomach and bowel. Sound waves do not penetrate air, making it harder to see target organs.

No, due to the gas (air) in the stomach and bowel, it’s hard to see these areas with ultrasound.

To date, no proven ill effects have been reported or seen during regular ultrasound exams on pregnant women.