Expert: Catherine Beier MS CBE - 6/30/2008

Question
My wife recently found out she was pregnant. We had seperated for a few months where she was sexually active with another man. On May 6th was the last time she had sex with this guy. We were intimate on May 15. The doctor said based on the ultrasound the baby was conceived on May 12, give or take 5 days. My wife seems to think these tests are inacurate, that she felt pregnant before I came back on the 15th, meaning the baby is not mine. However, when we had sex on the 15th, I ejaculated inside of her with no birth control. She became sick the next morning. I believe it is possible this baby is mine. What do you think?

Answer
Alex,

It's possible that either of you is the father.  It is doubtful, however, that she had any symptoms of pregnancy by the 16th of May.  At that point, implantation would be the most that is happening, which would typically not cause nausea or vomiting. If she was experiencing any symptoms, then it would be more likely that #1 was the father.

Without knowing more of her cycle history, the date of her last period, or how regular her cycles are, it's difficult to determine when she may have ovulated and give you a better indication of paternity.

Since the encounters are only 9 days apart, it's possible that either of you is the father. The only way to know for sure is with a paternity test.


Best,
Catherine