Natalya A Urakova ¹ and Aleksandr L Urakov² *

¹ PhD, Associate Professor of the Department of Neuropharmacology, Institute of Experimental Medicine, Saint-Petersburg, Russia
² MD, Professor, Head of the Department of General and Clinical Pharmacology, Izhevsk State Medical University, Izhevsk, Russia

*Corresponding Author: Aleksandr L Urakov, MD, Professor, Head of the Department of General and Clinical Pharmacology, Izhevsk State Medical University, Izhevsk, Russia.

Received: February 09, 2026 Published: February 28, 2026

Abstract

It has been established that fetal immobility is part of its reserves of adaptation to hypoxia, and the duration of fetal immobility during maternal apnea indicates their magnitude. Based on this, voluntary maternal apnea in the third trimester of pregnancy can be used to assess fetal resistance to hypoxia in order to predict the likelihood of newborn asphyxia. The fact is that during the normal course of pregnancy, the fetus remains motionless for at least 30 seconds from the moment of the onset of voluntary maternal apnea. In cases of symptoms of severe fetoplacental insufficiency, the fetus remains motionless for less than 10 seconds after the onset of apnea, after which convulsive contractions of the extremities occur in the fetus. It has been established that with good fetal resistance to hypoxia, there is a high probability that the fetus will be able to maintain its health until the end of pregnancy and natural childbirth. In the case of excessively low fetal resistance to hypoxia, continuation of pregnancy and natural delivery is contraindicated, since the probability of developing newborn asphyxia is high. Therefore, it is recommended to start urgent continuous hyperventilation of the mother’s lungs with gaseous oxygen until she develops symptoms of mild oxygen poisoning and at the same time a Сesarean section.

 Keywords: Pregnancy; Newborn Asphyxia; Intrauterine Hypoxia; Apnea; Oxygen; Immobility; Adaptation; Resistance; Encephalopathy

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Citation

Citation: Natalya A Urakova and Aleksandr L Urakov. “Duration of Fetal Immobility During Maternal Apnea Reflects its Resistance to Hypoxia". Acta Scientific Women's Health 9.3 (2026): 08-23.

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Copyright: © 2026 Natalya A Urakova and Aleksandr L Urakov. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.