Two possible fathers

I'm due September 23. I went to the doctors Wednesday and he said the ultrasound put me at 9 weeks
and 2 days. I was wondering how accurate that was? I was with my ex on December 30 and 31 but used
protection both times and then was with a close friend on January 2 but didn't use protection. According to my ultrasound taking off two weeks makes it that I conceived 7 weeks and 2
days ago which means its the first guys. Is that accurate or could my doctor be off a couple days?
The condoms we used were pretty new and I'm pretty sure they didn't tear.

[AnnieBrooke]

Hi, Lala,

When was the "Wednesday" when you had the ultrasound, the 20th?  And when was the first day of your last period?  Just counting on a calendar and assuming you meant the 20th, I get the possible date of conception of December 31, but could use a little more information.  

It's also important to say that when the difference is only 2 days, although it's possible in one's 7th week for an ultrasound to be exact, you really can't be certain with pinpoint precision.  Two days is just too close.  (If you had a condom mishap, sperm would be present in your system on January 1 from both guys.)

[Lala52068]

Yeah the 20th. And my last period was December 18th and my periods are about 30- 32 days apart.

[AnnieBrooke]

Well, the closeness of the dates with the two men make the range of possible conception dates for you on a calculator December 28 - January 5 with estimated ovulation date of December 31 or January 1.  Since January 1 is only one day before the second guy, you have to accept that possibly with just a tiny bit of variation such as the baby growing just a tiny bit faster than normal (though that's a bit unusual this early), ovulation could have been January 2.  In short, ultrasounds are not good enough to come down that finely.  You are definitely going to need a DNA test.  There are prenatal DNA tests if it is urgent to find out, but some brands are unreliable and all of them are quite expensive.  Doing a DNA test after the baby is born is less than half as costly and also accepted by the courts.  I'm sorry there is no immediate answer for you.

[Lala52068]

Ok that's what I thought. Thank you.
I'm going to get a prenatal dna test and hopefully find out sooner so I don't have to stress about who will be in the room when baby is born. Never thought I'd ever be in this position. :/
Oh and how likely is it that the condom broke? I wish I checked the condoms. Next time I will but really kicking myself for being stupid.

[AnnieBrooke]

Condoms can break, leak or slip.  It's not like you had to see something resembling a popped balloon to be at risk of pregnancy.

Be sure to do your research on the prenatal DNA tests out there.  They are quite expensive and some are notorious for being wrong.

Good luck, Lala.