What are the penalties of an 18 year old male getting a 14 year old female pregnant in Wisconsin?

It's likely going to fall under second degree sexual assault, which is a class c felony, and the term for that is imprisonment of up to 40 years, and if the perpetrator has a prior record that term can be increased. They might find other charges to tack on as well. This adult man needs to go see a local attorney asap and then he needs to stay completely away from little girls.