. Author manuscript; available in PMC: 2018 May 17.
Published in final edited form as: Contraception. 2017 Jul 8;96(4):233–241. doi: 10.1016/j.contraception.2017.06.014
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).