I postponed boards 3 years! The first year postponement was because my wife had our second child a few weeks before the boards; the second year was because I was in my second year of oncology fellowship; the third year was because I was finishing fellowship and a post-doc. I finally took it the fourth year (this past October 2013). Thankfully, I passed on the first attempt but my suggestion is to take it the first year. The longer you postpone, the harder it is to review the material. I was lucky because my co-fellow had also postponed the boards for 3 years so I had a study partner in the same boat. Both of us slowly started reviewing 6 months before the exam while balancing our new jobs as instructors/researchers because it was all such old material for both of us and we had to really review even the most basic gen peds concepts. It took probably 3x as much time to review material compared to those straight out of residency. It also took us longer to finish the exam (some newly graduated residents took the exam the same time and finished the exam much faster to finish; my friend and I used all the time allotted). Another disadvantage of postponing is that some material may have changed or become obsolete (vaccination regimens, antibiotic regimens, etc.). I completely understand the reasons to postpone but from my experience, things would actually have been easier if I took it right after residency. Nonetheless, you know what's best for yourself so there really isn't any right/wrong way to do it.