Fig. 1From: Circadian changes and sex-related differences in fetal heart rate parametersAnalysis of Day: Night Changes in Basal Fetal Heart Rate. The day:night change in basal fetal heart rate (bFHR) increased significantly with gestation age at the time of recording (r = −0.409; P < 0.002). The place of recording also exerted an additive significant effect (final r = −0.554; P < 0.001)Back to article page