Based on what we know, it's hard for Emily not to get pregnant, since her goal is to help the island's population increase. And even though there is a rule about not getting women on the island pregnant, I think that if Emily is so desperate to have a child and even her mother has seen her with Dylan and hasn't complained, then surely our redhead has the approval of Gina and the rest of the people to get pregnant with whoever she wants. The only thing I wonder is if this will create tension between Dylan and Brandi, and even Kelly (I still think that Kelly, at some point, will end up not only sleeping with Dylan but will get pregnant by him before Brandi does).
What I don't understand is what you're saying about a pregnancy ruining Dylan's goals: what goals, to fuck all the women on the island?