Glucose Test fail marginally

Itook my glucose test yesterday (KKH Private) and failed the 60 and 120 mins test by 0.9 mmol/l (ref range is 8.4, mine was 9.3). I am certain doctor will be pushing the idea of c-sect (am 24 weeks now) and will use my baby's size (currently weighing 690g which is the 90th percentile) as an excuse. I just need to know how to be firm on my decision for pro-natural and how do I get that message across clearly! Thank you in advance!