Why is ultrasound used in pregnancy, and when are extra scans needed?
Pregnancy ultrasound helps assess gestational age, the number of fetuses, growth, anatomy and the placenta. Timing depends on the care programme and clinical situation, with an anatomy scan usually offered in mid-pregnancy. Extra scans should have a clinical purpose rather than follow one universal schedule.
Details
Each stage has a purpose
Early imaging may date the pregnancy or assess symptoms. The mid-pregnancy anatomy scan, commonly around 18 to 22 weeks, examines fetal structures. Later scans may assess growth, the placenta or a maternal or fetal condition.
What does a normal result mean?
Ultrasound cannot detect every condition or congenital difference. A scan may need repeating because the baby’s position prevents a clear view, which does not automatically mean a problem was found. Ask what each examination can answer and whether follow-up is needed.
Appropriate medical use
The test uses sound waves rather than X-rays. A qualified professional should perform it for a medical reason; prolonged keepsake-only sessions are discouraged. Continue antenatal visits and other recommended tests even when the images are reassuring.
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