I think it is important. You get to see a little of everything, and really hone your skills. I started as a new grad on a med/surg floor, and think it was the best thing I could have done.

I think it's important to be as well-rounded as you can be, but if, in your heart, you are an OB nurse, then go with that. My only question is: Are you planning on becoming an L&D nurse? If, so, then some med/surg experience would be helpful, but not absolutely necessary. You can learn everything you need to be successful on your unit, if you are committed to learning it.

My first job as an RN was on an OB floor (after working 10 years as an LPN in long-term care). My first six months was spent doing straight postpartum (our hospital didn't do Mom/Baby), and then I went to L&D. I wouldn't call it an easy transition to L&D, but within 2 years, I was comfortable. Of course, my years as an LPN helped immensely, so I think your time as a CNA in OB will be especially useful.