Recruiting

Melatonin

Sponsor:

Brigham and Women's Hospital

Code:

NCT05358834

Conditions

Pregnant Women

Eligibility Criteria

Sex: Female

Age: 18 - 35

Healthy Volunteers: Accepted

Interventions

Melatonin

Placebo

Study Details

Brief summary:

The study will extend recent discoveries that have been made in basic human physiology related to responses melatonin and uterine contractions in late- or full-term pregnant women. The basic physiology work has been conducted in in vitro models of the human myometrium characterizing its responses to melatonin, and in pilot in vivo studies correlating the number of uterine contractions with melatonin concentrations that were manipulated by different types of light exposure. The planned experiments will test a causal link between circulating melatonin levels and uterine contractions in full-term pregnant women by manipulating melatonin levels using exogenous melatonin (i) during the day when endogenous levels of melatonin are very low (Experiment 1), and (ii) during the evening under conditions with lighting that would be expected to suppress the higher evening and nighttime levels of endogenous melatonin (Experiment 2).

Conditions

Pregnant Women

Study ID

NCT05358834

Start date

Jan 1, 2023

Status verified date

May, 2026

Completion date

Jun 30, 2027

Anticipated

Primary completion date

May 30, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: Female

Age: 18 - 35

Healthy Volunteers: Accepted

Inclusion Criteria:

  • nulliparity, age between 18 and 35,
  • BMI<36 pre-pregnancy,
  • ≥38 weeks of pregnancy with a single fetus at time of study.

Exclusion Criteria:

  • color blind;
  • prescription drugs affecting sleep, melatonin, and/or circadian rhythms (e.g., beta blockers, non-steroidal anti-inflammatory drugs);
  • a health or pregnancy related condition that might affect melatonin or uterine contractions;
  • medical conditions or medications for which melatonin might be contraindicated or there may be a drug interactions (e.g., Central Nervous System depressants/sedatives, Fluvoxamin (Luvox), medications for diabetes, immunosuppressants, anti-coagulants, Nifedipine, Verapamil).

Note: We cannot list all possible exclusionary criteria. Dr. Carolina Bibbo (co-I), our Obstetrics Investigator at Brigham and Women's Hospital (BWH), will make final determination of suitability including any safety concerns for each potential participant.

Study Design

Enrollment

120 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

placebo comparator: Daytime melatonin 0.0 mg

Daytime melatonin 0.0 mg

experimental: Daytime melatonin 0.5 mg

Daytime melatonin 0.5 mg

experimental: Daytime melatonin 3.0 mg

Daytime melatonin 3.0 mg

placebo comparator: Nighttime melatonin 0.0 mg

Nighttime melatonin 0.0 mg

experimental: Nighttime melatonin 0.5 mg

Nighttime melatonin 0.5 mg

Interventions

Melatonin

Oral melatonin administered as a single pill.

Placebo

Oral placebo administered as a single pill.

Primary outcome measure

  • Daytime: Total number of uterine contractions [ Time Frame: 10 hours ]
  • Nighttime: Total number of uterine contractions [ Time Frame: 4 hours ]

Central Contacts and Locations

Central contacts

Elizabeth B Klerman, MD PhD

617-643-2424ebklerman@hms.harvard.edu

Shadab A Rahman, PhD

617-525-8830sarahman@rics.bwh.harvard.edu

Locations

Brigham and Women's Hospital

Recruiting

Boston, Massachusetts, United States, 02115

Contacts

Elizabeth B Klerman, MD PhD

617-732-5500ebklerman@hms.harvard.edu

Principal Investigator:

Elizabeth Klerman, MD PhD

More Information

Sponsor

Brigham and Women's Hospital

Last update posted

May 18, 2026

Last verified

May, 2026

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Brigham and Women's Hospital on 2026-05-18.