Effects of Dim Light During Labor on Pain, Anxiety, and Labor Progress (DIM-LIGHT)

The Effects of Dim Light (≤80 Lux) Exposure During Labor on Pain, Anxiety, and Labor Progress: A Single-Center Randomized Controlled Trial

The environment of the labor room may influence how women experience childbirth. Light levels, in particular, may affect comfort, stress, and the course of labor. However, there is limited high-quality evidence on whether keeping the labor room lighting dim has measurable benefits for mothers.

This study aims to evaluate the effects of dim light exposure during active labor on pain, anxiety, and labor progress. Pregnant women who are in active labor at term will be randomly assigned to one of two groups. One group will give birth in a room with dim lighting (50-80 lux), while the other group will receive standard room lighting as part of routine care.

Pain and anxiety levels will be measured at specific time points during labor using standard assessment scales. Information about labor duration, use of labor medications, mode of delivery, and newborn outcomes will also be collected.

The dim light intervention does not interfere with routine obstetric care and does not pose additional risk to the mother or baby. If needed for clinical reasons, room lighting can be increased immediately. The results of this study may help determine whether a simple change in the birth environment can improve maternal comfort and labor outcomes.

Study Overview

• Status: Completed
• Conditions: Labor Progress; Labor Pain and Anxiety
• Intervention / Treatment: Other: Dim Light Exposure During Labor; Other: Routine Labor Room Lighting

Detailed Description

This study is a single-center, parallel-group randomized controlled trial designed to evaluate the effects of dim light exposure during active labor on maternal pain, anxiety, and labor progress. The trial is conducted in a university hospital labor ward and includes term pregnant women in active labor.

Eligible participants are women aged 18-45 years with a singleton, vertex-presenting pregnancy at ≥37 weeks of gestation who are in active labor. Eligible participants are individually randomized in a 1:1 ratio to either the dim-light intervention group or the standard-light control group using a predefined randomization sequence. Randomization is performed at the participant level after confirmation of eligibility and informed consent.

In the intervention group, labor room lighting is adjusted to a dim light environment with an illumination level maintained between 50 and 80 lux, using warm white or amber light sources. Light intensity is monitored at regular intervals using a lux meter. In the control group, routine labor room lighting conditions are maintained in accordance with standard clinical practice.

Pain intensity and anxiety levels are assessed at predefined time points during labor using validated measurement tools. Labor progress and obstetric outcomes, including use of labor augmentation, duration of labor stages, mode of delivery, and neonatal outcomes, are recorded from clinical charts.

The primary outcome is derived from changes in pain intensity over time during labor. Secondary outcomes include anxiety levels, labor characteristics, and maternal and neonatal clinical outcomes.

The dim light intervention is non-invasive and does not interfere with routine obstetric care. For clinical or safety reasons, room lighting can be increased immediately at any time at the discretion of the clinical team. All participants receive standard intrapartum care according to institutional protocols.

Study data are collected prospectively and stored in an anonymized format to ensure participant confidentiality. The study is conducted in accordance with ethical principles and has received approval from the relevant institutional ethics committee.

• Study Type: Interventional
• Enrollment (Actual): 120
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Niğde Province
    • Niğde, Niğde Province, Turkey (Türkiye)
      • Niğde Ömer Halisdemir University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Pregnant individuals aged 18-45 years

Singleton pregnancy

Vertex (cephalic) presentation

Gestational age ≥37 weeks

Active labor at enrollment (cervical dilation between 4 and 8 cm)

Ability to provide written informed consent

Exclusion Criteria:

Planned or ongoing epidural analgesia

Multiple pregnancy

Severe preeclampsia or other obstetric complications requiring immediate intervention

Known photosensitivity or light-related sensitivity disorders

History of psychiatric disorders that may interfere with anxiety assessment

Any condition deemed by the clinical team to require deviation from the study protocol

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Dim Light (50-80 Lux); Labor room lighting will be maintained at 50-80 lux using warm white/amber light sources. Illumination will be monitored at regular intervals with a lux meter. Standard intrapartum care will be provided; lighting may be increased immediately if clinically needed.	Other: Dim Light Exposure During Labor; Adjustment of labor room illumination to a target range of 50-80 lux during active labor, with monitoring using a lux meter; lighting can be increased at any time for clinical reasons.
Active Comparator: Routine Lighting (Control); Routine labor room lighting will be maintained according to standard clinical practice. Standard intrapartum care will be provided.	Other: Routine Labor Room Lighting; Standard labor room lighting conditions maintained according to routine clinical practice, without modification of illumination levels.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain intensity over time (VAS-AUC, 0-120 minutes)	Pain intensity will be assessed using a 0-10 Visual Analog Scale (VAS) at baseline (0 minutes), 60 minutes, and 120 minutes after allocation. The area under the curve (AUC) for VAS from 0 to 120 minutes will be calculated as the primary outcome.	From baseline to 120 minutes during active labor

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oxytocin use (initiation rate and total dose)	Proportion of participants who receive oxytocin augmentation and the total oxytocin dose administered during labor will be recorded from clinical charts.	During labor until delivery
Duration of active phase of labor	Time from enrollment during active labor to full cervical dilation will be recorded.	From enrollment to full dilation
Duration of second stage of labor	Time from full cervical dilation to delivery will be recorded.	From full dilation to delivery
Mode of delivery	Vaginal delivery (spontaneous/assisted) and cesarean delivery will be recorded.	At delivery
Estimated blood loss	Estimated maternal blood loss at delivery will be recorded from clinical records.	At delivery / immediate postpartum
Anxiety level (STAI-S change)	State anxiety will be assessed using the State-Trait Anxiety Inventory - State Anxiety Scale (STAI-S) at baseline (prior to intervention/exposure) and at 90 minutes during active labor. The STAI-S consists of 20 items, with total scores ranging from 20 to 80. Higher STAI-S scores indicate greater state anxiety (worse outcome). The primary analysis will use the change score (90-minute STAI-S minus baseline STAI-S); negative values indicate a reduction in anxiety.	From baseline to 90 minutes during active labor
Neonatal outcomes (Apgar scores)	Neonatal well-being will be assessed using the Apgar scoring system at 1 and 5 minutes after birth. The Apgar score ranges from 0 to 10, based on five components (heart rate, respiratory effort, muscle tone, reflex irritability, and skin color). Higher Apgar scores indicate better neonatal condition (better outcome). Apgar scores at 1 and 5 minutes will be recorded and analyzed descriptively.	1 and 5 minutes after birth

Collaborators and Investigators

• Sponsor: Pınar Erdoğan

Publications and helpful links

General Publications

• Buckley SJ. Executive Summary of Hormonal Physiology of Childbearing: Evidence and Implications for Women, Babies, and Maternity Care. J Perinat Educ. 2015;24(3):145-53. doi: 10.1891/1058-1243.24.3.145.
• Zsido AN, Teleki SA, Csokasi K, Rozsa S, Bandi SA. Development of the short version of the spielberger state-trait anxiety inventory. Psychiatry Res. 2020 Sep;291:113223. doi: 10.1016/j.psychres.2020.113223. Epub 2020 Jun 12.
• Wronding T, Argyraki A, Petersen JF, Topsoe MF, Petersen PM, Lokkegaard ECL. The aesthetic nature of the birthing room environment may alter the need for obstetrical interventions - an observational retrospective cohort study. Sci Rep. 2019 Jan 22;9(1):303. doi: 10.1038/s41598-018-36416-x.
• Balabanoff D. Color, light, and birth space design: An integrative review. Color Res Appl. 2023;48:413-32. doi: 10.1002/COL.22842
• Kazemi A, Beigi M, Najafabadi HE. Environmental factors influencing women's childbirth experiences in labor-delivery-recovery-postpartum unit: a qualitative cross-sectional study. BMC Pregnancy Childbirth. 2023 Mar 13;23(1):169. doi: 10.1186/s12884-023-05488-7.

Study record dates

Study Major Dates

• Study Start (Actual): January 6, 2026
• Primary Completion (Actual): May 29, 2026
• Study Completion (Actual): May 30, 2026

Study Registration Dates

• First Submitted: December 16, 2025
• First Submitted That Met QC Criteria: December 16, 2025
• First Posted (Actual): December 30, 2025

Study Record Updates

• Last Update Posted (Actual): June 2, 2026
• Last Update Submitted That Met QC Criteria: May 30, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Labor pain; Childbirth; Non-pharmacological intervention; Intrapartum care; Dim light; Lighting intensity; Labor room environment; Anxiety during labor
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Mental Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Anxiety Disorders; Labor Pain
• Other Study ID Numbers: 2025/131

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared due to the sensitive nature of intrapartum clinical data and the absence of participant consent for data sharing beyond the objectives of this study. De-identified aggregate results will be reported through publications.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No