Are ultrasound conception dates accurate?

[tina6146]

I discovered I was pregnant unexpectedly, and went to have an ultrasound on May 23rd. Due to having wavering periods, I never really keep track, and therefore I don't know when my last period was. I can give an "estimate" but I really don't know because I never keep track. (Plus I have always been told that because of metabolic issues, and PCOS that it would be very hard for me to get pregnant).
Anyway, not exactly proud of this, but I was with 2 different men in a two week time period. One I didn't use protection with on Saturday April 7th (we have been very good friends for years, and it just happened on a night out drinking/dancing) and the other man I only went out with a few times, and when we slept together the following week (on Saturday April 14th), the condom broke. I didn't think anything of it, because I am almost 38, and this has never happened to me before.
So, my question is, when I went to have my ultrasound, the sonographer did 2 measurements for the conception date: one was 6 weeks and 3 days, and the other one (just to be sure) was 6 weeks 5 days. So, we split the difference and said 6 weeks 4 days. This would make my conception date April 7th, which is the exact night I was with the first man.
Do you think there's a big chance that the 2nd man could potentially be the father? I am hoping the first man is indeed the father, because we have been friends for years, and it would be alot easier to handle. The second man, however, I don't even speak to anymore. I would hate for it to be the second man.
Any advice on people that have gone through this? I guess I just want some confirmation that these ultrasound dates are accurate. The ultrasound tech was amazing, and I feel like she really knew what she was doing, but I just want to make sure that these results couldn't be a whole 7-8 days off.

[AnnieBrooke]

Simplest thing is to call your doctor, and when he or she calls you back (don't pass a message along), say "My pregnancy measures seem to be lagging by two weeks.  Do you think my pregnancy is in trouble?"  He or she will give you better information than any speculation we do.

[Smokybaby]

This may be a long shot but I have a 13 month old she was born 28 June 2012 there were 2 guys I slept with around time of conception one was 14/15 October 2011 and the other was early to mid October. I was given a due date of 6th of July 2012 (keeping in mind this was from a 30 week dating scan because I didn't know I was pregnant til week 26) my question is I can't rule out the guy whom I slept with on 14/15 of October as the father? Also I can't remember my last missed period before I got pregnant

[AnnieBrooke]

If the baby was full term, like exactly 40 weeks, then that tends to suggest conception was the first week of October, or maybe as late as the 9th.  But do you know if she was full term?  

Unlike a lot of ladies on this site, you don't have to wait to find out, you can do a DNA test now and they are not that costly.  There is the drugstore kind, or you can go to a lab certified by the courts for establishing paternity.  (Call the family courts and ask the judge's clerk for the name of a local lab.)  If you think either guy will be unwilling to test, doing it through the court is the logical way, so nobody fakes the test.  (They can even be summonsed, I believe.)

[Smokybaby]

Thanks for replying. I didn't know I was pregnant until 26 weeks had dating scan at roughly 30 weeks the scanner lady was adamant I was due July 6th and from each consult with the doctor where he measured my belly I was always bang on the measurements of that week (with due date July 6th) the only thing that worries me is going by this date I could've conceived mid October but by birth date it's early October. As for her being full term I'm not sure she was 7 pound 6oz so I would think she was

[AnnieBrooke]

Sorry, unless you had had a really early ultrasound, I would not trust the July 6 due date to mean that much.  Also, it's not possible to judge full term vs. early just by the weight, I was just wondering if the doctor had commented on all her milestones indicating this.  I think if you want to be sure of the dad, you do need to do a (reliable) DNA test with one or the other of the men, or with both.  

[Smokybaby]

The doctor I dealt with has since passed away and she is a little bit delayed in term of milestones but not significantly so (sat up at 8 months, crawled at 11 and not walking now I never walked til 20 months) I'm going to get a DNA test thank you very much