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Consort diagrams for primary analysis (2000–2010) and secondary analysis (2015–2016)
a Comparison of pregnancies included in primary analysis to pregnancies excluded can be found in eTable 1.
b Comparison of pregnancies included in primary sub-analysis to pregnancies excluded can be found in eTable 2.
c Comparison of pregnancies included in secondary analysis to pregnancies excluded can be found in eTable 3.
