I don't believe Oregon's increase In population can be fixed with birth control.  It's migration from other states and locations that is providing our population increase.

Per the  PSU, Census Gurus:  

 "Net migration typically leads Oregon’s annual population change, while the natural increase is a relatively smaller and more stable component of population change. Between 1980 and 2012, Oregon’s net migration over the years has ranged from an increase of 63,200 residents to a decrease of 39,500 (Graph 1). During the same period, the natural population increase resulted in more consistent gains of between 11,600 and 20,900 residents per year."

We can't close the borders to Oregon, so we just have to suck them up.