RESUMEN
Analyzing the digital characteristics (chaotic and spectral features) of fetal and pregnant woman's heart period signal (HPS) can assess the autonomic nervous system function. Extracting and analyzing HPS of fetal and pregnant woman in perinatal period were realized by using the method of visual programming. The subjects were in supine position. Electrocardiography-signal (ECS) from the leads placed at symphysis pubic bone to inferior border of abdominal wall was acquired. ECS was preprocessed by wavelet filter. The sophisticated technique developed by our laboratory was used to analyze the digital characteristics of HPS. The system could be used to assess fetal and pregnant woman's autonomic nervous system function, furthermore, sympathetic and parasympathetic nervous function could be evaluated respectively and quantificationally. The system also could be used to prognosticate fetal distress. The digital characteristics of fetal and other age groups' HPS, which vary with age, suggest the physiological process of development, mature and senility of autonomic nervous system; based on it, we could find the way of anti-senility. Some digital parameters of fetal HPS stand between those of newborn and adult, which may imply that fetal autonomic nervous regulation is influenced by mother's nerve and endocrine system.