As a nurse you will be able to always get a job, weather it is a job that you want or not is different now. You may have to move to find the job you want or take a job that is Ok in the area that you want to live in. If I were you and wanted to stay in the same community I would take the job, work in the area that you have accepted the job in but keep your eyes open for an area that you want to work in. While keeping your eyes open do the best job that you can, put yourself out there go above and beyond. Your reputation will persuade nurse managers to offer you a position when an opening occurs.
I would also email, call, or introduce myself to the OB nurse manager. I would ask her when another NRP course is going to be offered, ask if you could attend it, you might not get paid for it but you might not have to pay for it. Also watch out for continuing education in the general area of OB, women’s health, Breast feeding, or any area that in some way applies to OB. Do not shy away from any education that the hospital offers you. Continuing education makes you more valuable to the organization and marketable to any other hospital. Keep certifications current even if you are not currently working in that area.
Keep your options open you just might find your niche, even if it is not what you originally wanted.