How long does pre cum last? It's been 4 days since unprotected sex, no full cum, just pre cum..

Not the Right? Successful pregnancies happen frequently with pre-ejaculation. It is not possible to absolutely prevent pregnancy from any form of birth control. Some try to do so by withdrawal as may in fact be the case for you, but, this is often without success. Emergency contraception is less successful after 4 days. Consider the new "ella" today if concerned and be more conscientious in the future.