An AFI of 8.51 cm at 35 weeks sits at the lower end of the normal range, not in the low range that usually needs urgent action. Fluid levels often dip a little in the third trimester. Your obstetrician will usually keep an eye on this rather than treat it aggressively unless it drops further.
Next Steps
Stay well hydrated through the day, since that is the one thing known to help fluid levels a little. Continue the iron,
calcium and other supplements your doctor has prescribed, and track your baby's movements daily. Ask your obstetrician whether a repeat scan in a week or two makes sense to recheck the level.
Health Tips
Go in sooner if your baby's movements reduce, you notice fluid leaking, or your bump feels smaller than before.