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. 2021 Nov 18;11:22519. doi: 10.1038/s41598-021-01976-y

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© The Author(s) 2021

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

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Flow chart of the study subjects. Clinical data were obtained from 2011 women who delivered at two tertiary centers or 12 primary maternity care units for whom two serial pregnancy records were available were obtained. A total of 1746 women were eligible for this study after excluding 196 and 69 women based on the index and subsequent pregnancy data, respectively.