Hi.. Precum, the prostrate secretion's can hjave viable sperms. Pregnancy can occur if there is deposition of the precum in the genital organs.. Especially when it is occurs 3 days before ovulation.. Though the chances are mild, you need to know all it takes is one sperm to cause pregnancy when there can be about 60million sperms per ml of the semen.. So if the one sperm is from the precum, it could still result in pregnancy.. So left upto you to make the choice..