Re: ultrasound dating dates dont match up with day of last period
ok so this is how my doctor explained it to me. for a woman with normal periods (28 day cycle) they will ovulate on day 14 of the cycle, you can get pregnant if you have sex from say day 12-15 of your cycle. you start counting your cycle on day one of your period. 27 days after your first day of your period, you will start your next period. most doctors go off the notion that you are having a 28 day cycle. its just easier to keep it all uniform. so going off this..if my calculations are right and you have around a 28 day cycle. you got pregnant the week of july 7th. your baby would be due 40 weeks after that week.
you have to give it some give and take though bc most women are not on a 28 day cycle and most women do not have sex on the exact day that they ovulate.
i know myself, i have a 26 day cycle. i ovulate around day 11-12 of each cycle. but of course when i go into to the doctors for all my tests and stuff, they quote you at being on a 28 day cycle.
hope i didnt confuse you!