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

University of Bergen

Status: Active, not recruiting

Conditions: Sleep Disturbance

Treatments: Device: Blue-blocking glasses; Device: Light grey control glasses

Study type: Interventional

Funder types: Other

Identifiers

NCT03114072

2016/1394/REK vest

Details and patient eligibility

About

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.

Full description

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.

Enrollment: 60 estimated patients

Sex: Female

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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60 participants in 2 patient groups

Blue-blocking glasses

Active Comparator group

Description:

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%.

Treatment:

Device: Blue-blocking glasses

Light grey control glasses

Active Comparator group

Description:

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%.

Treatment:

Device: Light grey control glasses