. Author manuscript; available in PMC: 2021 Jun 2.
Published in final edited form as: AJOG Glob Rep. 2021 Jan 27;1(1):100003. doi: 10.1016/j.xagr.2021.100003
This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)