How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Dr. C. Your Own Question
Dr. C.
Dr. C., Board Certified
Category: OB GYN
Satisfied Customers: 3064
Experience:  30 years of experience and an award-winning educator.
Type Your OB GYN Question Here...
Dr. C. is online now
A new question is answered every 9 seconds

I had sex 5 days apart from each other. Oct. 26 with one man

Customer Question

I had sex 5 days apart from each other. Oct. 26 with one man who was a pull out. And oct. 30, nov 2, and nov 4 with another with no pull out. I have twins and the vag ultrasound measures conception of nov 2. But is there still a chance they can belong to October 26 guy?
Last period was oct 13 so I was in ovulation.
Also, I took a pregnancy test on nov 9 that said negative and on the 15th it said 1-2 weeks.
Submitted: 1 year ago.
Category: OB GYN
Expert:  Dr. C. replied 1 year ago.

Hi, It's Dr. C. Board certified Ob-gyne. I can help you today.

I'm sorry for the situation. With only 5 days between the sex, it's not possible to rule out guy A 100%. The chance that he's the father is lower mostly because you used pull-out. Some guys are very good at pull out. But there is research that supports the possibility of sperm being present in pre-cum. The other problem is that sperm can easily live for 3 days inside women with reports of 5 and even 7 days. The ultrasound has an error rate of 3 days.

So with the ultrasound giving the most likely conception date of Nov 2, we need to add a 3 days error to that. So that makes possible conception from Oct 30. And if for some reason sperm lived for 4 days, that could mean that even if one sperm survived from the Oct 26th sex, that this pregnancy could be from guy 1.

So overall, it seems much more likely it's guy 2. But because the sex days are so close, we can't say 100%. In order to be 100%, paternity testing would be needed. This could involve blood from you and blood or a cheek swab for either guy.

I hope this was helpful. Please reply if I can explain anything better. I want to be sure you get the most helpful information possible for your situation.

Expert:  Dr. C. replied 1 year ago.

Any questions?