Taking long periods of time off?

For all the practicing CRNA's out there- Is it possible (or even safe) to take long periods of time off from work? (Say for example ~5-6 months for maternity leave or to take a long trip somewhere.) Do you loose the 'feel' for the job, or forget some of the little details that become second nature when you're working consistently? Was it difficult to pick up where you left off once you went back to work?