Hay, congrats sa 37 weeks! So "posterofundal high-lying grade 3" is actually about placenta position, it means your placenta is at the back upper part of your uterus and graded 3, which is normal naman for this stage of pregnancy! A few of us moms had similar findings, kaya don't worry too much. Grade 3 placenta is healthy and ready na for delivery, so that's actually good news. Best to confirm with your OB lang sa next check-up para ma-explain niya in detail kung paano siya positioned, pero from what I know this is totally normal at hindi yan issue, basta follow-up ka na lang regularly with your doctor para sure everything's progressing well! You're almost there, mama!