Ay, ganyan talaga ang dating ng scans, sobrang accurate sila kaya kung 39 weeks and 3 days na sabi ng ultrasound mo, yan na ang mas reliable EDD mo instead ng LMP, lalo na kung may discrepancy. Pero honestly, labor pain or no labor pain, ang katawan mo lang ang makakasiguro kung kailan talaga, kaya just be ready na anytime now at monitor mo lang ang contractions at any unusual signs, siguro na i-check mo rin sa OB mo kung okay lang mag-primrose at what dosage since may interaction siya with some meds. Good luck, mamsh!