Ah, primrose oil ay common talaga na binibigay ng OBs near term kasi it helps with cervical ripening and labor prep, pero since your OB prescribed it specifically for you at 36 weeks, seryoso mo na syang tanungin kung ano exactly ang gusto nyang makita or ma-achieve with it sa timeline mo, baka may specific reason sya based sa your pregnancy status or baby position. Better safe than sorry lagi pagdating sa meds and supplements, kahit natural, kaya confirm lang directly sa kanya kung okay na talaga for you at that exact week!