Pregnancy Risk After Unprotected Sex: A Doctor's Explanation

Question
Hello Dr. Rappaport

While we were intimate, I penetrated my girlfriend (both of us unprotected) but did not orgasm. She had had her period approximately 4-5 days prior. What are the chances of pregnancy occuring?

thanks!  

Answer
If your girlfriend has a normal 28 day cycle (from the first day of her period until the first day of her next period) ovulation occurs on cycle day #14. She can only conceive if she has unprotected sex on cycle day #13, 14, 15, or 16. She could not have ovulated on the 4th or 5th day of her cycle. Therefore, you are probably O.K.  Remember, there are around 300,000 sperm at the tip of the penis PRIOR TO ejaculation. If you try to withdraw the penis before ejaculation, these sperm may be "milked" into the vagina and she can become pregnant if it is around the  time of ovulation. I doubt that she ovulated that early in her cycle. If she does not get her next period, wait an additional seven days and take a pregnancy test. Then you will know for sure.