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Updated: Jul 19, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
[Circadian rhythms of human fetus and their coordination with its functioning]
Diurnal rhythms of cardiac activity and motion activity of expectant mother fetus with physiological course of pregnancy have been studied at pregnancy terms of 16-28 weeks. A new, original method of analysis of fetus has been proposed. It has been established, that healthy fetus exhibits sharply defined day-and-night variations of physiological functions. Biological rhythms of human fetus are in coordination with the condition of maternal body, but it is in counter phase with it. Dynamic curve of the changing of functioning level of its physiological systems carries biphasic character. "Active" (from 9 am till 2 pm and from 7 pm till 4 am) and "calm" (from 4 am till 9 am and from 2 pm till 7 pm) periods of human fetus have been chosen. The absence of sharply defined biorhythms in terms of 20-24 weeks gestation, shows its developmental retardation and needs timely correction. The results of investigations lay fundamentals of chronobiology and chronotheraphy of human fetus.
Diurnal rhythms of cardiac activity and motion activity of expectant mother fetus with physiological course of pregnancy have been studied at pregnancy terms of 16-28 weeks. A new, original method of analysis of fetus has been proposed. It has been established, that healthy fetus exhibits sharply defined day-and-night variations of physiological functions. Biological rhythms of human fetus are in coordination with the condition of maternal body, but it is in counter phase with it. Dynamic curve of the changing of functioning level of its physiological systems carries biphasic character. "Active" (from 9 am till 2 pm and from 7 pm till 4 am) and "calm" (from 4 am till 9 am and from 2 pm till 7 pm) periods of human fetus have been chosen. The absence of sharply defined biorhythms in terms of 20-24 weeks gestation, shows its developmental retardation and needs timely correction. The results of investigations lay fundamentals of chronobiology and chronotheraphy of human fetus.
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