A Phase 2 interventional study of Melatonin and Placebo in Gestational Diabetes, sponsored by Obstetrics & Gynecology Hospital of Fudan University. Not yet recruiting. Open to female participants aged 18 Years to 45 Years. Per ClinicalTrials.gov, last updated 2026-01-27.
Sponsored by Obstetrics & Gynecology Hospital of Fudan University · Phase 2, Interventional, and Treatment
The goal of this randomized, double-blind, placebo-controlled clinical trial is to evaluate whether melatonin supplementation improves glycemic control in pregnant women diagnosed with gestational diabetes mellitus (GDM).
The main question it aims to answer is:
Does melatonin supplementation help with glycemic control, especially in lowering fasting plasma glucose level?
Researchers will compare melatonin to a placebo (a look-alike substance that contains no melatonin) to see if melatonin works to improve glycemic control.
Participants will:
Exclusion Criteria:
1. Melatonin tablets will be administered orally 0.5 to 1 hour before sleep and at least 2 hours after the last meal. 2. Participants will take 5 mg melatonin every night during the first week of intervention after randomization, followed by 10 mg melatonin every night from the second week until delivery.
Drug: Melatonin
1. Identical placebo tablets in terms of packaging, appearance, smell and taste will be administered orally 0.5 to 1 hour before sleep and at least 2 hours after the last meal. 2. Participants will take identical placebo tablets after randomization until delivery.
Other: Placebo
1. Melatonin tablets will be administered orally 0.5 to 1 hour before sleep and at least 2 hours after the last meal. 2. Participants will take 5 mg melatonin every night during the first week of intervention after randomization, followed by 10 mg melatonin every night from the second week until delivery.
1. Identical placebo tablets in terms of packaging, appearance, smell and taste will be administered orally 0.5 to 1 hour before sleep and at least 2 hours after the last meal. 2. Participants will take identical placebo tablets after randomization until delivery.
Change in fasting plasma glucose (FPG) from baseline to 36 to 38 gestational weeks
The primary outcome is defined as the change in FPG levels from baseline, measured at the time of OGTT performed between 24 and 28 gestational weeks, to follow-up assessment at 36 to 38 gestational weeks. For participants who deliver before 36 gestational weeks, the last available FPG measurement obtained will be used.
Time frame: Baseline (24 to 28 gestational weeks), and 36 to 38 gestational weeks
Change in glycated hemoglobin (HbA1c) from baseline to 36 to 38 gestational weeks
This outcome is defined as change in HbA1c levels from baseline, measured at the time of OGTT performed between 24 and 28 gestational weeks, to follow-up assessment at 36 to 38 gestational weeks.
Time frame: Baseline and 36 to 38 gestational weeks
Initiation of insulin therapy
This outcome is defined as the proportion of participants requiring initiation of insulin therapy.
Time frame: From baseline until delivery
Change in mean glucose levels assessed by continuous glucose monitoring (CGM)
This outcome is defined as the change in mean glucose levels measured by CGM at baseline and before delivery.
Time frame: Baseline and 36 to 38 gestational weeks
Gestational weight gain in late pregnancy
This outcome is defined as total gestational weight gain and the rate of weight gain from baseline to the last assessment prior to delivery.
Time frame: From baseline until delivery
Incidence of intervention-related adverse events
This outcome is defined as the proportion of participants reporting adverse events potentially related to study intervention, including but not limited to dizziness, hypersomnia, nausea, vomiting and hypoglycemia. Adverse events will be collected from participants' medication diaries and systematically assessed through participant self-report at each antenatal clinic visit.
Time frame: From initiation of the intervention until 6 weeks postpartum
Impact of melatonin on fetal growth
The antenatal use of melatonin on estimated fetal growth (grams) will be assessed using ultrasound biometry parameters performed every two to four weeks following trial recruitment until birth.
Time frame: From baseline until delivery
Percentage of time in range, time above range, and time below range measured by CGM
This outcome is defined as percentages of time in range, time above range, and time below range measured by CGM at baseline and before delivery.
Time frame: Baseline and 36 to 38 gestational weeks
Pregnancy complications
This outcome is defined as a series of pregnancy complications including but not limited to gestational hypertensive disorders and intrahepatic cholestasis of pregnancy.
Time frame: From baseline until the end of follow-up at 6 weeks postpartum
Perinatal outcomes
This outcome is defined as a series of perinatal outcomes including but not limited to the percentages of macrosomia, large for gestational age, small for gestational age, neonatal hypoglycemia, birth trauma, cesarean section, postpartum hemorrhage, placenta abruption, and spontaneous premature rupture of membranes.
Time frame: From baseline until the end of follow-up at 6 weeks postpartum
No study locations are listed for this record.
Plan to share: No
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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Obstetrics & Gynecology Hospital of Fudan University