Pre cum

does pre cum usually occur when the guy has ejaculated once before ? For example 2nd round , or it happens all the time but the sperm is more likely to live if he did have that previous ejaculation & more likely to die if he didn’t ?

Also if you have sex raw for 3-5 mins with no ejaculation involved & go the rest of the way as well as other rounds with a condom can you get preg? (He ejaculates in condom as well as pulls out with it before)