Effects of Light on Melatonin and Contractions in Pregnant Women

Study Overview
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Brief Summary
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Specific Aim: Test the hypothesis that ocular light exposure will suppress melatonin secretion and reduce uterine contractions in women at late term pregnancies. Secondary aim. Test the hypothesis that ocular light exposure will reduce self-reported uterine contractions in women at late term pregnancies.

Official Title
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Effects of Light on Melatonin and Contractions in Pregnant Women

Conditions
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Pregnancy

Intervention / Treatment
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* Device: Lighting1
* Device: Lighting2


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: pregnant at 35-40 weeks first pregnancy Exclusion Criteria: pregnancy-related complications twin or higher pregnancy using medication that affects the sympathetic nervous system

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Lighting1<br>Ocular light exposure of a red wavelength light for one night | Device: Lighting1<br>* Ocular light exposure to a red wavelength light<br>|
| Experimental: Lighting2<br>Ocular light exposure of a blue-green wavelength light for one night | Device: Lighting2<br>* Ocular light exposure to a blue/green wavelength light<br>|
| Experimental: Lighting3<br>Ocular light exposure to a red wavelength light on night 1 and to a red wavelength light on night 2 | Device: Lighting1<br>* Ocular light exposure to a red wavelength light<br>|
| Experimental: Lighting4<br>Ocular light exposure to a red wavelength light on night 1 and to a blue-green wavelength light on night 2 | Device: Lighting1<br>* Ocular light exposure to a red wavelength light<br>Device: Lighting2<br>* Ocular light exposure to a blue/green wavelength light<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Melatonin Area Under the Curve (AUC) | Melatonin will be assessed using concentrations in saliva or blood. AUC will be calculated using melatonin concentrations during the Outcome Measure Time Frame. (1) for Lighting1 and Lighting2, the AUC for night 1; (2) for Lighting3 and Lighting4, the AUC for Night 2 | 4 hours of light exposure. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Uterine Contractions | Uterine contractions will be measured using a uterine tocometer device (1) for Lighting1 and Lighting2, the sum for night 1; (2) for Lighting3 and Lighting4, the sum for Night 2 | 4 hours of light exposure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pregnancy, Melatonin, Contractions, Light