Paternity Estimation: Calculating Potential Father of a Pregnancy

Question
The first day of my last period was July 9'th of 2007.  I had intercourse with a guy on the 15'th and then a different guy on the 21 & 22'nd.  Which would be more likely to be the father?

Answer
Dear Keshia,

If you have regular 28 day cycles, we expect you to ovulate about 14 days into each cycle. For you, with a LMP of 7/9, your estimated conception date would be 7/23 and your estimated due date is 4/14/08.

Therefore, the sexual encounter on 7/21 or 22 was most likely the one to result in the pregnancy.

I hope this has helped you and answered your question. I wish you well.

Brenda