Early Pregnancy Lifestyle and Glucose Patterns: A Substudy of TOFFFY

NCT07534670 | Not Yet Recruiting

• 1 other identifier: 2024/2120
• Study Type: interventional
• Target: 140
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this clinical trial is to examine how daily behavioral patterns in early pregnancy, including sleep, physical activity, and meal timing, influence continuous glucose dynamics and subsequent risk of gestational diabetes mellitus (GDM) in pregnant women without pre-existing diabetes. The main questions it aims to answer are:

1. 1.Do early-pregnancy chronobehavioral patterns (e.g., irregular sleep, night eating, and unstable rest-activity rhythms) relate to continuous glucose patterns measured using continuous glucose monitoring (CGM)?
2. 2.Can early behavioral and CGM-derived measures predict glucose regulation and metabolic outcomes later in pregnancy (24-28 weeks)?
3. 3.Does real-time self-monitoring using wearable devices and food logging improve glycemic outcomes compared to usual care?

Conditions

Continuous Glucose Monitoring; Diabetes, Gestational; Diet During Pregnancy; Meal Time; Actigraphy; Pregnancy; Glucose Intolerance During Pregnancy; Gestational Diabetes Mellitus in Pregnancy; Circadian Rhythm; Sleep; Chronobiology; Wearable Electronic Devices; Mobile Applications; Blood Glucose Profile; Metabolic Diseases; Randomized Controlled Trial; Pilot Study

Keywords

Risk factor; Lifestyle; Early pregnancy; Chrono-disruptive behaviours; Maternal health; Lifestyle intervention

Outcome Measures

Primary Outcomes (9)

• 24-hour glucose area under the curve (AUC)

  Continuous glucose monitor (CGM) using minimally invasive interstitial fluid extraction technology (MIET) will be used to assess 24-hour glucose exposure, expressed as area under the curve (AUC) (unit: mmol/L h). Higher AUC values indicate greater overall glucose exposure and poorer glycemic control.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Nocturnal glucose levels

  CGM will be used to assess mean nocturnal glucose levels during the sleep period. The ideal nocturnal glucose range is 3.9-10mmol/L). Higher values indicate poorer nocturnal glycemic control.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Glycemic variability - standard deviation (SD)

  CGM will be used to assess glycemic variability using the standard deviation (SD) of glucose values (unit: mmol/L), reflecting the dispersion from the average blood glucose level. Higher values indicate greater glycemic variability and poorer glycemic control.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Glycemic variability - coefficient of variation (CV)

  CV is an accepted index for evaluating within-day glycemic variability, where CV = (SD) / (mean glucose) × 100%. Higher values indicate greater glycemic variability and poorer glycemic control. A CV of ≥36% is commonly used to define high glycemic variability.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Rest-activity rhythm (RAR) - intra-daily variability (IV)

  Wrist actigraphy will be used to derive RAR by calculating the intra-daily variability (IV). IV reflects the degree of fragmentation in circadian activity patterns by assessing fluctuations in activity frequency and intensity within a given time period, capturing the extent of transitions between periods of rest and activity over time. IV values range from 0 to 1. Higher IV scores indicating poorer outcomes with greater disruption and fragmentation of the RAR.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Rest-activity rhythm (RAR) - inter-daily stability (IS)

  Wrist actigraphy will be used to derive RAR by calculating the inter-daily variability (IS). IS reflects the stability of 24-hour circadian activity variations and the balance between RAR and the circadian cycle. IV values range from 0 to 1. IS values close to 1 indicating a better RAR outcome with greater rhythm stability.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Chrononutrition behavior - meal timing

  AI-based food logging will be used to assess meal timing, defined as the timing of caloric intake, expressed as clock time of energy consumption. Later or more irregular intake timing indicates less favorable chrononutrition alignment.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Chrononutrition behavior - eating jetlag

  AI-based food logging will be used to assess eating jetlag, defined as the difference in timing of the caloric midpoint between weekdays and weekends (unit: hours). Higher values indicate greater circadian misalignment in eating behavior.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

• Chrononutrition behavior - frequency of night-eating

  AI-based food logging will be used to assess frequency of night-eating episodes, defined as the number of eating events occurring during the biological night or habitual sleep period. Higher night-eating frequency indicates poorer chrononutrition behavior.

  From enrollment in first trimester (≤13 weeks gestation), over 14 days

Secondary Outcomes (8)

• Glucose tolerance status during pregnancy

  From 24 weeks till 28 weeks of gestation

• Total glycemic exposure during pregnancy

  From 24 weeks till 28 weeks of gestation

• Glycemic marker - fasting insulin

  From 24 weeks till 28 weeks of gestation

• Glycemic marker - C-peptide

  From 24 weeks till 28 weeks of gestation

• Maternal glycemic control index - Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)

  From 24 weeks till 28 weeks of gestation

Study Arms (2)

Pilot arm

EXPERIMENTAL

Participants in this arm (n=70) will undergo a 14-day monitoring period in early pregnancy (≤13 weeks gestation). Participants will have real-time access to their glucose data and food logging feedback, enabling self-monitoring and potential behavioural adjustments. Participants will also continue to receive routine antenatal care and standard clinical assessments.

Device: Continuous glucose monitor (CGM); Device: Wrist actigraphy device; Behavioral: AI-based dietary and meal timing logging mobile application

Control Arm

NO INTERVENTION

Participants (n=70) receive routine antenatal care only, with no additional devices, monitoring, or feedback introduced by the study.

Interventions

Continuous glucose monitor (CGM) DEVICE

Participants will wear a continuous glucose monitor for 14 days in early pregnancy.

Pilot arm

Wrist actigraphy device DEVICE

A wrist actigraphy device will be used to assess sleep-wake patterns and physical activity over 14 days.

Pilot arm

AI-based dietary and meal timing logging mobile application BEHAVIORAL

Participants will record their dietary intake, meal timing logging, and feedback-based self-monitoring using an AI-based food logging mobile application.

Pilot arm

Eligibility Criteria

• Age: 21 Years - 39 Years
• Gender Eligibility Details: Eligibility is restricted to pregnant individuals in early gestation, which requires female biological reproductive capacity.
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Enrolled in the Towards Optimal Fertility, Fathering and Fatherhood studY (TOFFFY) (NCT06293235)
• Females who are currently pregnant and with viable intrauterine pregnancy at ≤13 weeks gestation at enrolment

You may not qualify if:

• Females with pre-existing diabetes mellitus (Type 1 or Type 2) and/or chronic medical conditions affecting glucose metabolism
• Females who are taking medications known to significantly affect glucose metabolism
• Females with multiple pregnancy (e.g., twins or higher-order gestation)
• Females who are unable to comply with study procedures, including: Inability to use smartphone-based applications and inability to wear wrist actigraphy device

Sponsors & Collaborators

• KK Women's and Children's Hospital: lead

Study Sites (1)

KK Women's and Children's Hospital

Singapore, Singapore, 229899, Singapore

Location

MeSH Terms

Conditions

Diabetes, Gestational; Metabolic Diseases

Condition Hierarchy (Ancestors)

Pregnancy Complications; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Diabetes Mellitus; Glucose Metabolism Disorders; Nutritional and Metabolic Diseases; Endocrine System Diseases

Study Officials

• See Ling Loy

  KK Women's and Children's Hospital

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Benjarat Oh

CONTACT

+6563948105; benjarat.oh@kkh.com.sg

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER GOV
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Junior Principal Investigator

Study Record Dates

• First Submitted: April 6, 2026
• First Posted: April 16, 2026
• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): April 30, 2027
• Study Completion (Estimated): June 30, 2027
• Last Updated: April 16, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

SG (1)