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?1446090952
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
134578_tn?1446090952
Comment
Comment
Submit Comment
Avatar_universal
IDK what i'm worried about.  Just trying to make myself feel better I guess.  Thank you.
Comment
Cancel
Avatar_universal
Comment
Comment
Submit 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
Avatar_universal
Comment
Comment
Submit Comment
134578_tn?1446090952
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
134578_tn?1446090952
Comment
Comment
Submit 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
1194973_tn?1385507504
Comment
Comment
Submit Comment
Your Answer
Avatar_universal
Answer
Know how to answer? Tap here to leave your answer...
Answer
Unsure if this is my baby
Submit Answer
A
A
Blank
Weight Tracker
Weight Tracker
Start Tracking Now
Maternal & Child Community Resources
RSS Expert Activity
233488_tn?1310696703
Blank
Marathon Running Done Over Many Yea...
May 21 by John C Hagan III, MD, FACS, FAAOBlank
233488_tn?1310696703
Blank
New Article on Multifocal IOL vs &q...
May 21 by John C Hagan III, MD, FACS, FAAOBlank
748543_tn?1443740527
Blank
TMJ/TMJ The Connection Between Teet...
01/15 by Hamidreza Nassery , DMD, FICOI, FAGD, FICCMOBlank
Top Children's Health Answerers
134578_tn?1446090952
Blank
AnnieBrooke
OR
13167_tn?1327197724
Blank
RockRose
Austin, TX
Avatar_f_tn
Blank
leviblack