Kintraia Paliko I, Zarnadze Medea G, Kintraia Nicolas P, Kashakashvili Ia G
K,V, Chachava Institute of Perinatalogy, Obstetrics and Gynecology, 38 Kostava Str,, Tbilisi 0108, Republic of Georgia.
J Circadian Rhythms. 2005 Mar 31;3(1):5. doi: 10.1186/1740-3391-3-5.
Very little is known about the perinatal genesis of circadian rhythmicity in the human fetus. Some researchers have found evidence of rhythmicity early on in fetal development, whereas others have observed a slow development of rhythmicity during several years after birth. METHOD: Rhythms of fetal heartbeat and locomotor activity were studied in women with physiological course of pregnancy at 16 to 40 gestational weeks. Observations were conducted continuously for 24 h using the method of external electrocardiography, which provided simultaneous detection of the changes in maternal and fetal heartbeat as well as assessment of daily locomotor activity of the fetus. During the night-time, electroencephalogram, myogram, oculogram and respiration of the mother were registered in parallel with fetal external electrocardiography. RESULTS: Although we found no significant daily rhythmicity in heart rate per se in the human fetus, we developed a new method for the assessment of 24-h fetal cardiotachogram that allowed us to identify daily rhythmicity in the short-term pattern of heart beating. We found that daily rhythmicity of fetal electrocardiogram resembles that of the mother; however, the phase of the rhythm is opposite to that of the mother. "Active" (from 9 a.m. to 2 p.m. and from 7 p.m. to 4 a.m.) and "quiet" (from 4 a.m. to 9 a.m. and from 2 p.m. to 7 p.m.) periods of activity were identified. CONCLUSION: A healthy fetus at gestational age of 16 to 20 weeks reveals pronounced rhythms of activity and locomotion. Absence of distinct rhythmicity within the term of 20 to 24 weeks points to developmental retardation. The "Z"-type fetal reaction, recorded during the "quiet" hours, does not indicate unsatisfactory state, but rather is suggestive of definite reduction of functional levels of the fetal physiological systems necessary for vital activity.
关于人类胎儿昼夜节律的围产期起源，我们所知甚少。一些研究人员在胎儿发育早期就发现了节律性的证据，而另一些人则观察到出生后数年节律性发展缓慢。方法：对妊娠16至40周生理妊娠过程的女性进行胎儿心跳和运动活动节律的研究。使用外部心电图方法连续进行24小时观察，该方法可同时检测母体和胎儿心跳的变化以及评估胎儿的日常运动活动。夜间，母亲的脑电图、肌电图、眼电图和呼吸与胎儿外部心电图同时记录。结果：虽然我们在人类胎儿心率本身未发现明显的每日节律性，但我们开发了一种评估24小时胎儿心动图的新方法，该方法使我们能够识别心跳短期模式中的每日节律性。我们发现胎儿心电图的每日节律性与母亲相似；然而，节律的相位与母亲相反。确定了“活跃”（上午9点至下午2点和晚上7点至凌晨4点）和“安静”（凌晨4点至上午9点和下午2点至晚上7点）活动期。结论：妊娠16至20周的健康胎儿表现出明显的活动和运动节律。20至24周内缺乏明显的节律性表明发育迟缓。在“安静”时间记录的“Z”型胎儿反应并不表明状态不佳，而是提示维持生命活动所需的胎儿生理系统功能水平明显降低。
