UUuummm....CindyB,
Hate to burst your bubble, but "I" got pregnant while
"on that wonderful little pill each and every day..." And other friends and relatives as well.
Two g/f's of mine also got pregnant AFTER a year of getting their tubes tied too.
As for the DNA thing, everybody has their OWN DNA, like finger prints, so is the DNA issue. But hopefully, you won't have to cum to that!
Wife of CyberMWCouple