Is the 4d scan accurate

My daughter is 30 weeks pregnant and went for a 4d scan yesterday.The scan showed that the baby's head is big and looks like 33 weeks and that the baby is not geeting enough food from the placenta,is this a concern and what now? She will see her gynea only on theusday,is this too late? What should we do?

Wait till Tuesday and have her ask. That is a question best asked of her OB, not the internet.