Um...

Why do you want to quit? From "they want to suspend", I take it to mean that they're just going to put your orientation on hold until you're able to return... not put you on disciplinary suspension. You have a job waiting for you when your childcare issues resolve. Not many places do that. I wouldn't quit.

A former classmate of mine could only orientate once a week becuse of issuses. The LTC facility worked with her. You sould ask to orientate when you can.

I need to hear a bit more; what did they mean by 'suspend'? Are they holding your position until you can resolve your issues? Do they have a high turnover of nurses? Because if they do, it is for a reason. I'd ask them to clarify what they mean by suspend before I quit. But, you have to do what is right for you because you work to live, not live to work, and if your life is not in balance, then, it may be better to find an alternative position.

If you decide to quit I don't think it's necessary to put it in writing if you haven't even been through orientation yet. Just simply don't use them on the application for your next job.