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Dr. Phil, MD
Dr. Phil, MD, Board Certified Physician
Category: Medical
Satisfied Customers: 58357
Experience:  GP in the United States
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Can dating scans be wrong by up to 4 weeks?

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Can dating scans be wrong by up to 4 weeks?
Hello. I'm Dr. Phil, licensed and practicing internist. Excellent service is my goal.

Thanks for this question

Yes, in certain circumstances this is very possible.

Anatomy could be altered or the child could be very small or very large.

This would be unusual but to answer your question, this is possible
Dr. Phil, MD and other Medical Specialists are ready to help you
Customer: replied 3 years ago.

I am due on 6.8.14.


I know this is going to sound stupid, but I just want to eliminate all worry form ym mind cos its stressing me out a bit.


on the 30th Sept last year I had sex with someone that wasn't my current partner. They tell me they didn't ejaculate. I took the morning after pill straight away the next morning.


I bled a week later as I know can sometimes happen. Then another very light period at the end of the month. My periods usually occurred from the 25th of each month in the past.


My partner and I had been trying for a baby. late November I found out i was pregnant. I had the dating scan which gave 6th August.


I am just trying to eliminate all the worry and I know I am probably worrying about nothing. But I am very big, and my baby is going to be huge. I am worried they got the date wrong and that this is a baby from the 30th sept. I know that sometimes the MAP doesn't work. But the 2nd bleed in October surely must have been a period right?


If the 30th sept was conceptino date, then I would eb due in early JUly, but SURELY a dating scan can't be that much out??



I think you have nothing to worry about Emma.

You took the morning after pill (which is highly effective) plus your dates would have to be way off.

I think you are fine.
Customer: replied 3 years ago.

Thanks Dr Phil, you've put my mind at rest.


I have a tendency to worry about things execessively!

you're welcome

please don't forget a positive rating. I appreciate it
I appreciate the excellent rating.

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