Fig. 2

Linear regression analysis between right myocardial performance index (RMPI) and gestational age (GA). a Correlation between RMPI and GA in SP fetus (r2 = 0.1015). b Correlation between RMPI and GA in IVF fetus (r2 = 0.0007). c Correlation between RMPI and HR in SP fetus (r2 = 0.0005). d Correlation between RMPI and HR in IVF fetus (r2 = 0.0196)