Article Text

Original research
Effects of bright light therapy for depression during pregnancy: a randomised, double-blind controlled trial
  1. Babette Bais1,
  2. Astrid M Kamperman1,
  3. Hilmar H Bijma2,
  4. Witte JG Hoogendijk1,
  5. Jan L Souman3,
  6. Esther Knijff1,
  7. Mijke P Lambregtse-van den Berg1,4
  1. 1Psychiatry, Erasmus Medical Center, Rotterdam, Zuid-Holland, The Netherlands
  2. 2Obstetrics and Gynaecology, Erasmus Medical Center, Rotterdam, Zuid-Holland, The Netherlands
  3. 3Lighting Applications, Signify NV, Eindhoven, Noord-Brabant, The Netherlands
  4. 4Child and Adolescent Psychiatry/Psychology, Erasmus Medical Center, Rotterdam, Zuid-Holland, The Netherlands
  1. Correspondence to Dr Babette Bais; b.bais{at}


Objectives Approximately 11%–13% of pregnant women suffer from depression. Bright light therapy (BLT) is a promising treatment, combining direct availability, sufficient efficacy, low costs and high safety for both mother and child. Here, we examined the effects of BLT on depression during pregnancy.

Design Randomised, double-blind controlled trial.

Setting Primary and secondary care in The Netherlands, from November 2016 to March 2019.

Participants 67 pregnant women (12–32 weeks gestational age) with a DSM-5 diagnosis of depressive disorder (Diagnostic and Statistical Manual of Mental Disorders).

Interventions Participants were randomly allocated to treatment with either BLT (9000 lux, 5000 K) or dim red light therapy (DRLT, 100 lux, 2700 K), which is considered placebo. For 6 weeks, both groups were treated daily at home for 30 min on awakening. Follow-up took place weekly during the intervention, after 6 weeks of therapy, 3 and 10 weeks after treatment and 2 months postpartum.

Primary and secondary outcome measures Depressive symptoms were measured primarily with the Structured Interview Guide for the Hamilton Depression Scale—Seasonal Affective Disorder. Secondary measures were the Hamilton Rating Scale for Depression and the Edinburgh Postnatal Depression Scale. Changes in rating scale scores of these questionnaires over time were analysed using generalised linear mixed models.

Results Median depression scores decreased by 40.6%–53.1% in the BLT group and by 50.9%–66.7% in the DRLT group. We found no statistically significant difference in symptom change scores between BLT and DRLT. Sensitivity and post-hoc analyses did not change our findings.

Conclusions Depressive symptoms of pregnant women with depression improved in both treatment arms. More research is necessary to determine whether these responses represent true treatment effects, non-specific treatment responses, placebo effects or a combination hereof.

Trial registration number NTR5476.

  • depression & mood disorders
  • obstetrics
  • psychiatry

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  • Contributors ML-vdB is the project’s principle investigator and initiator of the study, obtained funding and designed the study. BB was responsible for recruiting and counselling participants, running the study and collecting data. AMK is the project’s methodologist and executed the primary statistical analysis. HHB and EK were involved in the recruitment of the study. JLS provided support. AMK, WJGH and ML-vdB supervised the study. BB, AMK and ML-vbB prepared the original draft. All authors reviewed, edited and approved the final manuscript.

  • Funding MLB received funding from the ‘Light, Cognition, Behaviour and Health’ program of The Netherlands Organization for Health Research and Development (NWO; The Hague, The Netherlands), in collaboration with Signify Research (grant number 058-14-003) to fund the current study.

  • Competing interests JLS is employed by Signify Research. The lamps used in this study were provided by Signify Research.

  • Patient consent for publication Not required.

  • Ethics approval All procedures performed involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. Written informed consent was obtained from all participants. The study protocol and later amendments were approved by the medical ethical committee of the Erasmus University Medical Centre, Rotterdam, The Netherlands (registration number MEC-2015–731).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available upon reasonable request. The datasets used and/or analysed during the current study are available from the author Mijke Lambregste-van den Berg on reasonable request.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.