Table 1.
Parameters of fetal heart rate variability.
Table 2.
Fetal state of activity.
Fig 1.
Developmental course of ACTAMP20 (a-c) and SDNN (d-f) in the linear mixed model. (a, d) unclassified datasets, (b, e) fetal active sleep, (c, f) fetal quiescence. x–Segment of Interest {< 27 WGA; 27–30 WGA; 31–35 WGA; >35 WGA}; completed weeks of GA; y–Estimator in [ms] units. Numerical data see Table 2. Significant (p<0.05) contrasts are marked by *, trends (p<0.10) by +.
Fig 2.
Developmental course of gMSE(3) (a, b) and skewness (c, d) in the linear mixed model. (a) unclassified datasets: SoI {1–2} χ2 = 11,81; p<0.001, SoI {2–3} χ2 = 10.04; p = 0.0013; (b) fetal active sleep SoI {1–2} χ2 = 6.7, p = 0.0096, SoI {2–3} χ2 = 12.17, p<0.001; (c) unclassified datasets: SoI {1–2} χ2 = 70.31, p<0.0001, SoI {2–3} χ2 = 21.29, p<0.001, SoI {3–4} χ2 = 3.16, p = 0.076; (d) fetal active sleep: SoI {1–2} χ2 = 35.50, p<0.0001, SoI {2–3} χ2 = 21.13, p<0.0001. x–Segment of Interest {< 27 WGA; 27–30 WGA; 31–35 WGA;>35 WGA}; completed weeks of GA; y–Estimator in [bitnorm] Significant (p<0.05) contrasts are marked by *, trends (p<0.10) by +. Results for ‘fetal quiescence’ are not shown because they did not reach significant levels (gMSE(3): SoI {2–3}, χ2 = 3.41; p = 0.07).
Fig 3.
Developmental course of pNN5 in the linear mixed model.
(a) unclassified datasets, (b) fetal active sleep, (c) fetal quiescence. x–Segment of Interest {< 27 WGA; 27–30 WGA; 31–35 WGA; >35 WGA}; completed weeks of GA; y–Estimator in [%]. Numerical data see Table 2. Significant (p<0.05) contrasts are marked by *, trends (p<0.10) by +.
Table 3.
Contrast analysis of fHRV parameters between pregnancy segments of interest.
Fig 4.
Autonomic maturation as reflected by heart rate regulation.
Schematic summary of the findings for illustration purposes. The scales of the individual components contributing to heart rate regulation are arbitrary and do not reflect absolute values, but coincidental qualitative changes throughout the second half of gestation.