. Author manuscript; available in PMC: 2017 Apr 28.
Published in final edited form as: Eur J Obstet Gynecol Reprod Biol. 2015 Jul 8;193:51–60. doi: 10.1016/j.ejogrb.2015.06.031
This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
Figure 1.
Flow chart of the study population