First ultrasound said she was 8w5d. that is what was on the u/s. does the us add the two weeks on or does the doctor.

All built in: You may want to find the many tools available to you online for your pregnancy. That dating builds in the "LMP" "two weeks'. I recommend that you have at least one prenatal guide book and here is a link to a conception calculator that will bring you much information and entertainment: http://www.babymed.com/conception-calculator.

It does: John, The ultrasound takes the two weeks for ovulation and conception into account. Remember that first trimester ultrasounds (up to 14 weeks) can be off by 1 week in either direction. That means the fetus could be between 7 weeks 5 days, and 9 weeks 5 days. I hope this helps, and congratulations!