. 2019 Jun 6;2019(3):hoz010. doi: 10.1093/hropen/hoz010
© The Author(s) 2019. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com
Figure 1.
Preferred reporting items for systematic reviews and meta-analysis flow diagram.