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NCT Number: NCT03114072

Blocking Blue Light in Pregnancy, Effects on Melatonin Profile and Sleep

Sleep disturbances are common in pregnancy, and the incidence increases during the third trimester. Light and specially the blue wavelengths of light, is affecting sleep and the circadian rhythm. The main aim of this randomized controlled study is to investigate the effect of Blue-blocking glasses (BB-glasses) used in the evening and night on sleep and mood in pregnant women in the third trimester. The outcome measures assess sleep variables, alertness, melatonin level, sleepiness (subjectively), mood and symptoms of anxiety and depression. In addition we want to measure the pregnancy related sleep problems, alcohol intake, physical activity and perceives stress in the study population, and the association with daily/nightly light exposure.

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Key information

Conditions

Sleep Disturbance Dyssomnias Mental Disorders Nervous System Diseases Parasomnias Sleep Disorders, Intrinsic Sleep Initiation and Maintenance Disorders Sleep Wake Disorders

Sex eligibility

Female

Study type

Interventional

Phase

Not applicable

Primary location

Randi Liset

Bergen, 5232, Norway

About this study

Several hormonal and mechanical influences can cause insomnia in pregnancy, and insomnia has been reported by 62% of pregnant women, a number that is significantly higher than found in the general population (10-15%). Disrupted sleep among pregnant women also includes nocturia (a frequent need to get up and urinate at night), dyspnea (shortness of breath), nasal congestion, muscular aches and pelvic pains, fetal activity, leg cramps as well as reflux.

Artificial light in the evening and during the night increases alertness, disturbs sleep, shifts the timing of the circadian clock and impairs the brains' restorative slow waves during deep sleep. Recent studies have however shown that use of BB-glasses in the evening improves sleep quality (subjectively reported) among persons with insomnia, and prevent alertness caused by blue-light emitting screens which are part of devices such as smart-phones and tablets.

This project will contribute with new knowledge on how filtering nightly light exposure in pregnant women in their third trimester affects their sleep and mood. Importantly, the project initiates new research on a potential non-pharmacological treatment of sleep disturbances by blocking blue wavelengths of light in the evening and during nocturnal awakenings. Blue light is known to increase alertness through a recently described retinal receptor; the intrinsically photoresponsive retinal ganglion cell (IpRGC), specialized for detecting daytime light signal. This project is highly innovative and may have significant practical implications Due to the variety of aims and outcome measures, we plan to present the outcomes in separate articles.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • nulliparous women
  • expecting one child
  • being in the third trimester of a normal pregnancy
  • able to wear an actigraph during daytime and nighttime
  • able to fill out a questionnaire in Norwegian

Exclusion criteria

  • somatic or psychiatric disorders
  • fever and other health conditions affecting sleep
  • working at night during the study protocol

Treatment and study plan

Blue-blocking glasses

Device

Wear the BB-glasses from three hours before bedtime, and if needed to turn on the light, also during the night.

Other names: Virtual darkness eyewear, orange glasses

Light grey control glasses

Device

Wear the light grey glasses from three hours before bedtime, and if needed to turn on the light, also during the night.

Other names: Grey sunglasses

Primary outcomes

  1. Sleep diary

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Daily subjective estimates of sleep variables, and will be assessed every morning.

  2. Change in motor activity measured by using Actigraphy.

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Objective measure by Actiwatch Spectrum from Philips Respironics. The participants will use the Actiwatch for the whole study period of three weeks.

  3. Melatonin level

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measured by saliva samples.

Secondary outcomes

  1. Bergen Insomnia Scale (BIS)

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    The BIS measure subjective symptoms of insomnia during the previous week, and will be assessed at day 1 and day 21 of the study period.

  2. Karolinska Sleepiness Scale (KSS)

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measure subjective sleepiness just prior to turning the lights off, and will be assessed every evening in the study period.

  3. Evening activation

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measured subjectively by the Pre-Sleep Arousal Scale (PSAS).

  4. Sleepiness (subjectively)

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measured by the Epworth Sleepiness Scale (ESS).

  5. Mood

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measured by the self-report forms Positive and Negative Affect Schedule.

  6. The Beck Anxiety Inventory (BAI)

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measure subjective symptoms of anxiety, and will be assessed at day 1 and day 21 of the study period.

  7. The Beck Depression Inventory-II (BAI-II)

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measure subjective symptoms of depression during the last week, and will be assessed at day 1 and day 21 of the study period.

  8. Common pregnancy complaints Questionnaire

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measure subjective complaints during the last night, assessed every morning of the study period.

  9. Cortisol level

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measured by saliva samples, assessed at day 7 and day 21 of the study period.

  10. Alpha Amylase level

    Time frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31

    Measured by saliva samples, assessed at day 7 and day 21 of the study period

Sponsors and collaborators

Lead sponsor

University of Bergen

Other

Collaborators

  • The Norwegian Competence Center for Sleep Disorders (SOVno)
  • Western Norway University of Applied Sciences

Registry information

Official study title

Nightly Light Exposure in Pregnancy: Blue-blocking Glasses as an Intervention to Ease Sleep Disturbances and to Improve Mood

Important dates

Study start
2017
Primary completion
2019
Study completion
2026
First posted
Apr 14, 2017
Registry last updated
Dec 18, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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