so yes the ultrasound is the most accurate thing there is, like i said my doctor was thinking i was almost 10 weeks because of my period they just look at this little round chart that says the first day of your last period and by that date underneath it is your due date. i hope you get peace of mind and be save overseas!!god bless you and all the military a woman is most fertile two weeks after the first day of her last period. the first day of her period was jan 1, her most fertile days would be around the 14th of jan. it depends on how many days she has between her periods.the odds are leaning more toward him with the research i have done.im deploying to afghanistan soon and need the peace of mind if thats my kid or his? I had a rough estimate of when me and my husband got pregnant but when i found out i thought i was about 9 weeks along when i got into the doctor they went back to the first day of my last period.its pretty accurate Okay, the first day of the period is what matters.
some women have a regular 28 days some women have up to 35+.if she has 35 days between her periods than the u/s could say she is later than she really is. that also means that her fertile days are later than the two weeks a regular 28 day woman would have.i was spotting and cramping so i did an ultrasound.that revealed i was only 8 weeks 6 days pregnant and was 4 days after my doctor visit.
like i said count the days she has between periods and calculate her most fertile days.theres an app called "my days" you can download and p her info in.