How effective is growth scan for twin and multiple pregnancy?

The scan measures each baby separately, including body dimensions used to estimate weight. It can compare growth patterns, amniotic fluid and blood flow, while also checking the placenta and the relationship between babies. Differences may be expected, but a widening gap or a change in one baby's growth can prompt closer review.

Accuracy can be harder when babies are close together or their positions make images difficult. The scan cannot by itself diagnose every complication of multiple pregnancy. The type of placental arrangement and the trend across examinations affect how the findings are interpreted.

Keep the scan schedule set by your multiple-pregnancy team, even when you feel well. Bring previous reports so measurements can be compared, and ask which baby is being measured during each part of the examination. Follow advice about blood pressure, fetal movements and any additional heart-rate or Doppler monitoring.

Ask what difference between babies is concerning in your pregnancy and how the result could alter follow-up or birth planning. A growth scan guides surveillance rather than treating a problem directly. Read about [Growth Scan](/treatments/pregnancy-and-birth-care/growth-scan/).

Contact your maternity unit promptly for reduced or changed movement from one or more babies, vaginal bleeding, leaking fluid, painful regular contractions or severe abdominal pain. Seek urgent advice for a severe headache, visual changes, sudden swelling or feeling seriously unwell, as multiple pregnancy can need rapid assessment when these symptoms occur.

Ask whether the babies share a placenta or amniotic sac, how each baby's growth compares with the last scan, and whether fluid or Doppler findings are reassuring. Confirm the next scan date, who to call about movement changes, and which findings could affect delivery planning.