Fetal and Neonatal Diastolic Myocardial Strain Rate: Normal Reference Ranges and Reproducibility in a Prospective, Longitudinal Cohort of Pregnancies

Fetal measures of diastolic strain rate have acceptable reproducibility after 24 weeks' gestation. The described changes across gestation likely reflect intrinsic myocardial adaptation to loading conditions. These reference ranges can be used to assess effects of various disease states on fetal myocardial deformation.