iugr at 31 weeks?

I'm 31 weeks and baby is measuring 2 lbs 14 oz. the dr never said it's iugr but I had it with my previous pregnancy and he was delivered due to preeclampsia. My blood pressure and everything else has been fine this time, baby is just measuring small. Has anyone had experience with this? My maternal fetal medicine dr mentioned delivered at 37 weeks but the baby is already so small...