Is it possible

[nikkichicken]

I had sex with GUY A a day or two before my period which came Sept 23.
My period was regular, normal flow and lenght.

Then after my period I had sex with GUY B and only GUY B up until I found out I was pregnant around Nov.

I had a couple of dating scans one at 6 weeks and other at 9 weeks. Both were on schedule for me to have a due date of June 30th until I got around 20 weeks when they changed my due date to June 21st based upon a ultrasound.

I just need some ressurance that guy b is the father.

oh and my period before my Sept 23rd one was Aug 26th.

[AnnieBrooke]

The conception calculator gives you the following based on the due date from your early ultrasound (which is the accurate one).  Between that and the fact that the sex with Guy A was before your period, don't worry about a thing.

     First day of last menstrual period:  September 23
     Probable date of ovulation:  October 7
     Possible dates of conception:  October 3 to 11
     Due date:  June 30 (40 weeks)

[lmechelle]

It's very unlikely to ovulate so closely to your period. Even if you did it takes up to ten days to inbed in the lining of your uteris. And ultrasound are less acurate the further along you are. Devide the number of days your average period is in half..and that's likely when you ovulated. Even though it is possible to bleed during implation, it usually doesn't happen intil 8 days after the egg has been fertelized. Hope that helps!