When's it acceptable to stop working?

Right now I work a part time and a full time job and I'm 28 weeks pregnant with my first , my works don't really have "maternity leaves" and my boyfriend is getting a job at the end of the month (waiting because he has to help his parents) but after he gets working full time. When is it okay to stop working and just relax and get things ready for the baby before she comes? I feel bad asking him to work and basically putting all the financial responsibilities on him.. I just don't wanna seem like I'm wimping out early with working because I'm pregnant..