Hi mama! Primrose oil works differently for everyone talaga, a few of us tried it around that time and some felt effects within a few days, habang iba naman it took a week or two pa. Since you're already at 38 weeks and 2cm na, that's progress! But honestly, check with your OB about how you're progressing and kung okay lang talaga for you ang primrose, kasi bawat pregnancy is different and they'll know best what's safe for your situation. Good luck with everything, you're almost there na!