hi my last period was on November 5th and i just found out that i was pregnant and me and my boyfriend have been together for 2 1/2 yrs and havent gotten pregnant and i cheated on him on November 15th(only this day), so is it possible to tell by ultrasound if i conceived on that day or after that. so will i be able to tell whos the father of my baby by how far along i am?
HI I understand your concern.  Conception is around ovulation which is 14 days prior to expected day of menses. So ovulation can be calculated. Now if November 15th happened to be your ovulation time (or a couple of days before or after that). You have possibility of conception with sex on 15th Nov. Sonography can not calculate date of conception. It reports in terms of weeks of pregnancy.  Confirmed Paternity can be tested by chromosomal analysis only.  Thanks.