Pregnancy
Conditions
Keywords
Pregnancy, Melatonin, Contractions, Light
Brief summary
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.
Interventions
DEVICELighting1
Ocular light exposure to a red wavelength light
DEVICELighting2
Ocular light exposure to a blue/green wavelength light
Sponsors
Harvard University
National Institutes of Health (NIH)
Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
Brigham and Women's Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 35 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Melatonin Area Under the Curve (AUC) | 4 hours of light exposure. | 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 |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Uterine Contractions | 4 hours of light exposure | 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 |
Other
| Measure | Time frame | Description |
|---|---|---|
| Subjective Assessment of Uterine Contractions | 4 hours of light exposure | Self-reported uterine contractions will be assessed by asking the women how many contractions they felt. (1) for Lighting1 and Lighting2, the sum for night 1; (2) for Lighting3 and Lighting4, the sum for Night 2 |
Countries
United States
Participant flow
Pre-assignment details
51 people total enrolled 33 started study; 18 were not studied. 18 people who signed informed consent were not studied: 3 had a new medical reason for ineligibility 5 delivered the baby before their scheduled study date 8 signed consent forms but were not studied because study enrollment was complete before their scheduled study data 2 were lost to follow-up
Participants by arm
| Arm | Count |
|---|---|
| Lighting1 Ocular light exposure of a red wavelength light for one night
Lighting1: Ocular light exposure to a red wavelength light | 4 |
| Lighting2 Ocular light exposure of a blue-green wavelength light for one night
Lighting2: Ocular light exposure to a blue/green wavelength light | 4 |
| Lighting3 Ocular light exposure to a red wavelength light on night 1 and to a red wavelength light on night 2
Lighting1: Ocular light exposure to a red wavelength light | 8 |
| Lighting4 Ocular light exposure to a red wavelength light on night 1 and to a blue-green wavelength light on night 2
Lighting1: Ocular light exposure to a red wavelength light
Lighting2: Ocular light exposure to a blue/green wavelength light | 9 |
| Total | 25 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 | FG003 |
|---|---|---|---|---|---|
| Overall Study | Physician Decision | 0 | 0 | 1 | 0 |
| Overall Study | Withdrawal by Subject | 1 | 0 | 1 | 2 |
Baseline characteristics
| Characteristic | Lighting1 | Lighting2 | Lighting3 | Lighting4 | Total |
|---|---|---|---|---|---|
| Age, Continuous | 24.8 years STANDARD_DEVIATION 5.4 | 23.0 years STANDARD_DEVIATION 4.7 | 27.5 years STANDARD_DEVIATION 4.9 | 30.4 years STANDARD_DEVIATION 3.2 | 27.4 years STANDARD_DEVIATION 4.9 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 1 Participants | 1 Participants | 2 Participants | 2 Participants | 6 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 3 Participants | 3 Participants | 6 Participants | 7 Participants | 19 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Gestational age | 37.9 weeks STANDARD_DEVIATION 1.2 | 37.6 weeks STANDARD_DEVIATION 1.2 | 38.3 weeks STANDARD_DEVIATION 0.4 | 37.7 weeks STANDARD_DEVIATION 1.1 | 37.9 weeks STANDARD_DEVIATION 0.9 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants | 1 Participants | 1 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants | 3 Participants | 2 Participants | 1 Participants | 7 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 1 Participants | 0 Participants | 0 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) White | 2 Participants | 1 Participants | 5 Participants | 7 Participants | 15 Participants |
| Sex: Female, Male Female | 4 Participants | 4 Participants | 8 Participants | 9 Participants | 25 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk |
|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 4 | 0 / 4 | 0 / 10 | 0 / 10 |
| other Total, other adverse events | 0 / 4 | 0 / 4 | 0 / 10 | 0 / 10 |
| serious Total, serious adverse events | 0 / 4 | 0 / 4 | 0 / 10 | 0 / 10 |
Outcome results
Primary
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
Time frame: 4 hours of light exposure.
Population: Healthy pregnant women. In Lighting3, there were missing data from 2 participants; in Lighting4, there were missing data from 1 participant
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Lighting1 | Melatonin Area Under the Curve (AUC) | 42.1 area under curve (h*pg/mL) | Standard Deviation 23 |
| Lighting2 | Melatonin Area Under the Curve (AUC) | 24.3 area under curve (h*pg/mL) | Standard Deviation 24.8 |
| Lighting3 | Melatonin Area Under the Curve (AUC) | 38.5 area under curve (h*pg/mL) | Standard Deviation 14.6 |
| Lighting4 | Melatonin Area Under the Curve (AUC) | 26.3 area under curve (h*pg/mL) | Standard Deviation 39.8 |
p-value: 0.334t-test, 2 sided
p-value: 0.423t-test, 2 sided
Secondary
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
Time frame: 4 hours of light exposure
Population: Healthy pregnant women. In Lighting3, there were missing data from 2 participants; in Lighting4, there were missing data from 1 participant
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Lighting1 | Uterine Contractions | 16.8 number of uterine contractions | Standard Deviation 10.9 |
| Lighting2 | Uterine Contractions | 13.8 number of uterine contractions | Standard Deviation 17.3 |
| Lighting3 | Uterine Contractions | 14.5 number of uterine contractions | Standard Deviation 9.1 |
| Lighting4 | Uterine Contractions | 13.0 number of uterine contractions | Standard Deviation 12.8 |
p-value: 0.78t-test, 2 sided
p-value: 0.791t-test, 2 sided
Other Pre-specified
Subjective Assessment of Uterine Contractions
Self-reported uterine contractions will be assessed by asking the women how many contractions they felt. (1) for Lighting1 and Lighting2, the sum for night 1; (2) for Lighting3 and Lighting4, the sum for Night 2
Time frame: 4 hours of light exposure
Population: Healthy pregnant women. In Lighting3, there were missing data from 2 participants; in Lighting4, there were missing data from 1 participant.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Lighting1 | Subjective Assessment of Uterine Contractions | 4.0 number of uterine contractions | Standard Deviation 6.1 |
| Lighting2 | Subjective Assessment of Uterine Contractions | 3.5 number of uterine contractions | Standard Deviation 2.4 |
| Lighting3 | Subjective Assessment of Uterine Contractions | 5.5 number of uterine contractions | Standard Deviation 4.9 |
| Lighting4 | Subjective Assessment of Uterine Contractions | 2.9 number of uterine contractions | Standard Deviation 4.5 |
p-value: 0.883t-test, 2 sided
p-value: 0.271t-test, 2 sided