Alhamdulillah, babies yang besar pun boleh lahir normal, sis! A few of my mum friends who are petite macam you juga beranak babies weighing 3.8kg to 4.2kg without issues, so your track record is actually really encouraging, and normal delivery pulak! Your body dah proven ia boleh handle bigger babies, so jangan worry sangat even though this one macam on the bigger side already. Since you're 37 weeks at 3.1kg, baby masih ade space to grow naturally, and paediatric weights kat ultrasound pun boleh have margin of error je. Check with your doc la on the next visit for reassurance and to make sure everything's progressing well, they'll guide you based on your actual measurements and history. You've got this, mama!