Make a Plan
Once you know your rights and your boss's inclinations, you can decide what plan works best for you. Factor in your budget, the availability of affordable childcare in your area, and your gut feelings about how long a leave you'd like to take.
Whatever you decide, clearly communicate what you want from your boss, both verbally and in a memo. Specifically, your memo should include the terms of your leave: the number of weeks of paid maternity or disability leave; any vacation or personal days; and any additional unpaid leave.
It should also include a list of your duties, what tasks you expect to have completed when you leave, and suggestions as to how your work can be handled while you're out. If your job is multifaceted, you can suggest delegating your work to a number of people.