Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Sleep-Wake Cycles01:24

Sleep-Wake Cycles

Sleep is an essential physiological process vital to maintaining overall well-being. The reticular activating system (RAS), a network of neurons in the brainstem, regulates wakefulness and sleep. While it may seem passive, sleep consists of distinct cycles, each with its unique characteristics and functions. Two key sleep phases are non-rapid eye movement (NREM) and  rapid eye movement (REM).
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
Stages of Sleep01:22

Stages of Sleep

Sleep progresses through distinct stages, each characterized by specific brain wave patterns and physiological responses ranging from wakefulness to stages of non-rapid eye movement, known as non-REM, to rapid eye movement, referred to as REM. Understanding these stages helps in recognizing how sleep supports various bodily and cognitive functions.
Before sleep begins, in wakefulness, the brain exhibits primarily beta waves, which are high in frequency and low in amplitude, indicating alertness...
Fetal Circulation01:14

Fetal Circulation

Fetal circulation is a unique system that facilitates the exchange of gases, nutrients, and waste products between the developing fetus and the mother. This intricate process takes place through a special organ called the placenta.
Two umbilical arteries transport blood from the fetus to the placenta. At the placenta, the blood absorbs oxygen and nutrients while simultaneously eliminating waste products. This oxygen-enriched and nutrient-rich blood then returns to the fetus through one...
Brain Waves01:23

Brain Waves

Brain waves are electrical signals generated by the neurons in the brain, which are regularly monitored to measure mental activities. Brain waves and their frequency ranges can be measured using an electroencephalogram or EEG. There are four main types of brain waves, each with distinct characteristics:
Understanding Sleep01:11

Understanding Sleep

Sleep, an essential biological state, involves significant reductions in physical activity, sensory awareness, and interaction with the environment. This complex physiological process is primarily regulated by specific brain regions, notably the hypothalamus and pons, which govern the sleep-wake cycle or circadian rhythm.
The circadian rhythm, a nearly 24-hour cycle, is deeply influenced by environmental light cues. Light exposure directly affects the hypothalamus, which in turn regulates...
REM Sleep Behavior Disorder01:15

REM Sleep Behavior Disorder

REM Sleep Behavior Disorder (RBD) is a sleep disorder characterized by the absence of muscle paralysis that normally occurs during the REM phase of sleep. This absence allows individuals to physically act out their dreams, which are often vivid and disturbing. Common behaviors exhibited during episodes include kicking, punching, and yelling. These actions can be dangerous, potentially leading to injuries for the person with RBD or their bed partner.
RBD is significantly associated with...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Placental Assessment Using Microvascular Flow Imaging: Reference Ranges and Clinical Application.

Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine·2026
Same author

Inter-rater reliability and clinical utility of the modified ferriman-gallwey scale in routine practice.

Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology·2026
Same author

Severe adverse cardiac events in pregnant women with congenital heart disease at a university hospital in southern Thailand.

International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics·2026
Same author

Response: A risk scoring model for predicting adverse maternal outcomes in pregnancy with pre-eclampsia.

International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics·2025
Same author

Cerebral-Placental-Uterine Ratio in the Early Third Trimester as a Predictor of Small-for-Gestational-Age Birthweight: A Prospective Cohort Study.

Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC·2025
Same author

Maternal Adiposity in the First Trimester Pregnancy as a Predictor of Gestational Diabetes Mellitus: A Prospective Cohort Study.

Journal of ultrasound in medicine : official journal of the American Institute of Ultrasound in Medicine·2025

Related Experiment Video

Updated: Jun 23, 2026

How to Obtain Reliable Visual Event-related Potentials in Newborns
07:39

How to Obtain Reliable Visual Event-related Potentials in Newborns

Published on: October 24, 2019

Sleep-wake cycles in normal fetuses.

Chitkasaem Suwanrath1, Thitima Suntharasaj

  • 1Department of Obstetrics and Gynecology, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand. schitkas@yahoo.co.uk

Archives of Gynecology and Obstetrics
|May 13, 2009
PubMed
Summary
This summary is machine-generated.

Normal fetal sleep-wake cycles were established using fetal heart rate (FHR) tracings. Fetuses aged 30-40 weeks show significant variation in sleep-wake states.

More Related Videos

P50 Sensory Gating in Infants
12:55

P50 Sensory Gating in Infants

Published on: December 26, 2013

Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice
10:56

Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice

Published on: August 2, 2017

Related Experiment Videos

Last Updated: Jun 23, 2026

How to Obtain Reliable Visual Event-related Potentials in Newborns
07:39

How to Obtain Reliable Visual Event-related Potentials in Newborns

Published on: October 24, 2019

P50 Sensory Gating in Infants
12:55

P50 Sensory Gating in Infants

Published on: December 26, 2013

Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice
10:56

Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice

Published on: August 2, 2017

Area of Science:

  • Perinatology
  • Fetal Physiology
  • Sleep Medicine

Background:

  • Sleep-wake cycles are crucial for fetal development.
  • Understanding normal fetal sleep patterns is essential for assessing fetal well-being.
  • Previous studies have limited data on the variability of these cycles.

Purpose of the Study:

  • To establish normal ranges for fetal sleep-wake cycles.
  • To analyze variations in sleep-wake patterns in fetuses between 30 and 40 weeks of gestation.

Main Methods:

  • Analysis of 600 fetal heart rate (FHR) tracings from uncomplicated singleton pregnancies.
  • Recordings were 1-hour in duration, from fetuses between 30 and 40 weeks gestational age.
  • Independent interpretation of FHR recordings by two obstetricians.

Main Results:

  • The mean baseline FHR was 141.6 (7.6) beats/min.
  • Median time spent in a quiet state was 26% (0-88.6%), with a median duration of 15.7 minutes.
  • Quiet and active states were observed in 84% of fetuses; FHR accelerations increased with gestational age, while baseline FHR decreased.

Conclusions:

  • Normal ranges for fetal sleep-wake cycles were successfully established.
  • Significant variability exists in the percentage of time fetuses (30-40 weeks) spend in sleep-wake states.