Each of you could also take part of your 2017 RMD in 2017 and the remainder in 2018 before April 1. If you file jointly, for the most part it doesn't really matter which of you chooses to take some or all of your RMD in 2018 instead of 2017; whichever one of you delays some of the RMD 2018, that income is delayed to 2018 on your joint tax return.
