Can a girl get pregnant from a blowjob

20 Things You Can't Get Pregnant From. Sexual health - NHS. The scientific name for morning wood is "nocturnal penile tumescence", and it doesn't actually have anything to do with sex. An egg only lives for about a day but sperm can be sniffing around far longer. Sex during pregnancy. Myth You can use plastic bags instead of condoms False: Never use a polythene bag or cling film instead of a condom.