I may get laid off during maternity leave, is this legal?

Yes, this legal. As your company told you, you are not eligible for FMLA, so they have no obligation to hold your job. That's nice of them to basically tell you that they will take you back anyway, as long as they have a position open. No, you are not eligible for unemployment. First of all, you would not be laid off. You would essentially be fired with cause for abandoning your job. Or you would have to quit. Quitting would look much better. People quit jobs to have babies every day. But you wouldn't be able to collect if you are fired for cause or if you quit. Second, unemployment is only for those willing, able, and available to work. If you are able, willing, and available to work, why not just keep your current job? If your delivery makes you not able to work, you can't collect unemployment.