
Pregnant, Ultrasound Showed Small Sac. What Could Be The Meaning?

Thanks for your query.
If you had conceived on 4th of March, then right now you would be 6 weeks pregnant by the ultrasound on 1st April.
Also, if you had conceived on 24th of February, then you would be 7 weeks pregnant by ultrasound on 24th of March.
The weeks of pregnancy are calculated from the date of last menstrual period, and not from day of conception.
ALso, first trimester ultrasounds do have intrinsic error margin of 4 - 5 days.
Hence, you cannot categorically say when you conceived based on the ultrasound.
In viable pregnancies, a transvaginal ultrasound should be able to detect the gestational sac by 5 weeks.
The days are so close by ( merely a week ) that early pregnancy ultrasound can hardly differentiate between the two.
It would help me if you provide me with details of your menstrual cycles - date of your last menstrual period, normal cycle length and duration.
Also, the exact ultrasound report if scanned and sent, or typed word to word, would provide more information.
Looking forward to hearing from you soon.
Take care.


If you can provide the exact ultrasound report, I might be able to opine better.
If the acts were with two different persons, a DNA test might tell you when the conception occurred.
If the two acts were with the same person, it is next to impossible to opine, and it anyways hardly matters, because the pregnancy would be dated by your first ultrasound scan, and not by your LMP date.


So based off the information I gave you does that help with figuring out that I can exclude those days ?
Can you type the exact report ?
Unless you had sex with your regular partner in the intervening period, between 24 th feb and 4th of march, chances are high you conceived with your boyfriend.
EXACT ultrasound report would help, as I repeatedly mention.


4 weeks by ultrasound means that conception or ovulation occurred only two weeks back.
That would rule out conception by your boyfriend then.
It would all fall in the domain of speculation and percentages till you go for a DNA test.


My bad.
I meant that it is more likely that conception occurred with your regular partner, instead of the two exceptions that you cheated.


Yes, cardiac activity is visualized generally around 6 weeks.
So if the doctor just saw a sac, you definitely must be 4 - 5 weeks.
Thats correct.

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