Aa
A
A
Close
Avatar universal
Unsure if this is my baby
My girlfriend and I are expecting our first child.   Her last menstrual cycle was september 4th.  Had our 1st ultrasound on november 2nd which states that she was 8 weeks and 4 days pregnant.  I am just concerned because we had been broke up.  She had sex with another man on july 31st.  Is there anyway possible the ultrasound could have been off by that much?  It would have been off by 4 to 6 weeks???
Cancel
5 Answers
Page 1 of 1
134578 tn?1483549754
Don't worry.  Conception date would have been around September 16th.  The July 31st date has nothing to do with anything.  Ultrasounds, especially at 8 weeks 4 days, are quite accurate, maybe off by a day or two.  (Later in the pregnancy they are less accurate, because babies grow at different rates.  But so early, they can be spot-on to the exact day.  They are never off by 4-6 weeks.)  

Pregnancy is counted from the first day of the last period.  Given an 8w4d count on November 2nd, the expected day of the first day of her last period would be September 2, so everything lines up.  She would have conceived a couple of weeks later than the first day of her last period, so, around the 16th.  If she had a period in early September, she would have also probably had one in early August, meaning that she had two periods after the sex on July 31st.  So what are you worried about?
Comment
Cancel
Comment
Avatar universal
Comment
Comment
Comment
Post Comment
Avatar universal
IDK what i'm worried about.  Just trying to make myself feel better I guess.  Thank you.
Comment
Cancel
Comment
Avatar universal
Comment
Comment
Comment
Post Comment
Avatar universal
She did have a period in august and september.  But you always hear of those women who have periods while pregnant.  Just makes my mind wonder i guess.
Comment
Cancel
Comment
Avatar universal
Comment
Comment
Comment
Post Comment
134578 tn?1483549754
The ultrasound would have said she was 14 weeks pregnant or more if she got pregnant in July.  If the thing that is bothering you is that she had a fling in July, discuss that issue with her separately, but the baby was conceived in mid September.  Good luck!
Comment
Cancel
Comment
Avatar universal
Comment
Comment
Comment
Post Comment
1194973 tn?1385507504
Periods aren't possible while pregnant. If she had indeed gotten pregnant in July/early august she would be much further along.
Comment
Cancel
Comment
Avatar universal
Comment
Comment
Comment
Post Comment
Your Answer
Avatar universal
Answer
Do you know how to answer? Tap here to leave your answer...
Answer
Answer
Post Answer
A
A
Blank
Weight Tracker
Weight Tracker
Start Tracking Now
Women's Health: Postpartum Community Resources