<s>[INST] hi, i am pregnant at the 9th month and the baby my arrive in a fortnight. but the dating is not exact because of ultrasonic test is not reliable, my doctor says, which could be because of my pregnancy diabetes, what should do. is there a way i can show my test result to see if there is other interpretations about my pregnancy date? [/INST] Hi Thanks for the query. I understand your concern - Mostly expected date of delivery is conventionally calculated by adding 9 months & 8 days to the 1st day of last menstruation.  Still nobody can definitely predict about exact date of delivery. . So it can be plus or minus 8 days from The calculated date.  -Some people believe it to be 40 weeks from last menstrual date. Here also it stands variation of 1 week more or less.  -babies off pregnancy diabetes women tend to be overweight... that is why the error in calculation.  Please don't bother about this calculation. Continue to visit your treating obstratitian as per her instructions... She would guide you for betterment of you your child.  Thanks </s>