"Get you pregnant" is right, but you ought to be aware that "a man that get you pregnant" is as wrong as it can be: it is not only entirely unidiomatic but also ungrammatical.
A good command of colloquial usage in the target language is a prerequisite for translating dialogue.
As for differences between varieties of Spanish, there are resources available online that can help, particularly the RAE's
Diccionario de americanismos:
http://lema.rae.es/damer/Usage specific to particular countries is also indicated in the DLE itself:
http://www.rae.es/It will nearly always be the case that if no specific regional meaning is indicated for a word in these dictionaries, its meaning is the same throughout the Spanish-speaking world.