Effects of Dim Light During Labor on Pain, Anxiety, and Labor Progress

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.

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