Blocking Blue Light in Pregnancy, Effects on Melatonin Profile and Sleep
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT03114072 |
Recruitment Status :
Active, not recruiting
First Posted : April 14, 2017
Last Update Posted : May 8, 2019
|
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Sleep Disturbance | Device: Blue-blocking glasses Device: Light grey control glasses | Not Applicable |
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.
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 60 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Investigator) |
Masking Description: | Consenting participants will be randomized (by www.randomizer.org) to either intervention/control condition. The intervention- and control glasses will be covered in the same looking wrapping, done by a third person, which will blind the investigator as well. |
Primary Purpose: | Treatment |
Official Title: | Nightly Light Exposure in Pregnancy: Blue-blocking Glasses as an Intervention to Ease Sleep Disturbances and to Improve Mood |
Actual Study Start Date : | June 6, 2017 |
Actual Primary Completion Date : | April 9, 2019 |
Estimated Study Completion Date : | August 2020 |
Arm | Intervention/treatment |
---|---|
Active Comparator: Blue-blocking glasses
N=30 The Blue-blocking glasses (orange-tinted), which remove more than 99% of the blue wavelengths (wavelengths within the visible spectrum shorter than 530 nm). Luminous transmittance: 50%.
|
Device: Blue-blocking glasses
Wear the BB-glasses from three hours before bedtime, and if needed to turn on the light, also during the night.
Other Name: Virtual darkness eyewear, orange glasses |
Active Comparator: Light grey control glasses
N=30 Partially blue blocking light grey glasses, blocking only about 50% of blue wavelengths (wavelengths within the visible spectra shorter than 530 nm). Luminous transmittance: 55%.
|
Device: Light grey control glasses
Wear the light grey glasses from three hours before bedtime, and if needed to turn on the light, also during the night.
Other Name: Grey sunglasses |
- 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.
- 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.
- Melatonin level [ Time Frame: 2 weeks in the third trimester of pregnancy, mainly gestational week 29-31 ]Measured by saliva samples.
- 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.
- 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.
- 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).
- Sleepiness (subjectively) [ Time Frame: 3 weeks in the third trimester of pregnancy, mainly gestational week 28-31 ]Measured by the Epworth Sleepiness Scale (ESS).
- 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.
- 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.
- 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.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | Child, Adult, Older Adult |
Sexes Eligible for Study: | Female |
Gender Based Eligibility: | Yes |
Gender Eligibility Description: | Pregnant human beings are female. |
Accepts Healthy Volunteers: | No |
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

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03114072
Norway | |
University of Bergen | |
Christiesgate 12, Bergen, Norway, 5020 |
Principal Investigator: | Randi Liset, PhD student | University of Bergen |

Publications:
Responsible Party: | Randi Liset, Principal Investigator, University of Bergen |
ClinicalTrials.gov Identifier: | NCT03114072 |
Other Study ID Numbers: |
2016/1394/REK vest |
First Posted: | April 14, 2017 Key Record Dates |
Last Update Posted: | May 8, 2019 |
Last Verified: | May 2019 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
Pregnancy Blue-blockers Sleep quality Melatonin |
Dyssomnias Parasomnias Sleep Wake Disorders Nervous System Diseases Mental Disorders Methamphetamine Central Nervous System Stimulants Physiological Effects of Drugs Sympathomimetics Autonomic Agents |
Peripheral Nervous System Agents Dopamine Agents Neurotransmitter Agents Molecular Mechanisms of Pharmacological Action Adrenergic Agents Adrenergic Uptake Inhibitors Neurotransmitter Uptake Inhibitors Membrane Transport Modulators Dopamine Uptake Inhibitors |