NCT06477120 · University of Illinois at Chicago
Time-restricted Eating Among Pregnant Females With Severe Obesity
(TRE-Preg)
What this study is about
In the United States, a body mass index (BMI) of at least 35.0 kg/m2 affects about 15% of women of reproductive age. Severe obesity is a significant predictor of adverse perinatal outcomes including gestational diabetes mellitus, pre-eclampsia, premature birth, and at its most severe, fetal death, birth defects and a three-fold greater risk of maternal mortality.
View original scientific description
In the United States, a body mass index (BMI) of at least 35.0 kg/m2 affects about 15% of women of reproductive age. Severe obesity is a significant predictor of adverse perinatal outcomes including gestational diabetes mellitus, pre-eclampsia, premature birth, and at its most severe, fetal death, birth defects and a three-fold greater risk of maternal mortality. Observational studies suggest weight maintenance and even modest body fat loss and altering the maternal metabolic milieu (availability of glucose and lipids) in the gestational period may be important to reducing perinatal health risks among pregnant females with severe obesity. The proposed research aims to assess time-restricted eating in the 2nd and 3rd trimesters of pregnancy to explore the effects on maternal weight, and perinatal health outcomes compared to standard clinical care.
Interventions
BEHAVIORAL
Time Restricted Eating
The time-restricted eating arm will be instructed to eat ad libitum during an 8-hr window daily (10am - 6pm OR 11am - 7pm) in the 2nd trimester and 10-hr eating window from (9am - 7pm OR 10am - 8pm) in the 3rd trimester and abstain from caloric foods and beverages for the remaining 14-16 hours.
Primary outcome measures
Recruitment Feasibility
Time frame: From 6 months through 32 months (the funding period is 36 months)
≥ 30% of those approached enroll
Trial safety - Maternal Complete Blood Count
Time frame: Baseline (14-20 weeks gestational age) and monthly through labor and delivery, about 6 months
% and n with abnormal results by study arm
Trial safety - Non-stress Test for Fetal Safety
Time frame: 29-31 weeks gestational age and 35-37 weeks gestational age
Measured with a fetal monitor to examine baby's heart rate over time (usually 20 to 30 minutes, but sometimes up to an hour) % and n with abnormal results by study arm
Intervention acceptability
Time frame: 25-27 weeks gestational age and 35-37 weeks gestational age
Semi-structured interviews
Research visit feasibility
Time frame: Baseline, 25-27 weeks gestational age and 35-37 weeks gestational age
Number of data collection visits completed with \>=80% completed at each timepoint and completeness of data
Intervention (TRE) session feasibility
Time frame: Weekly from baseline through labor and delivery, about 6 months
Number and % of intervention sessions completed by TRE participants
TRE adherence
Time frame: Daily from enrollment to labor and delivery (TRE arm only), about 6 months
Response rate to daily text message regarding eating start and stop time to determine adherence to the eating window goal is \>= 80% adherence on days reported
Trial safety - Maternal health checks
Time frame: Weekly from baseline to labor and delivery, about 6 months, % and n for health events reported by study arm
Weekly maternal health checks via videoconference in TRE and control group that is verified with electronic health record
Trial safety - Maternal outcomes
Time frame: Labor and delivery
Data obtained from the participant's electronic health record (gestational age at delivery, gestational diabetes, gestational hypertension, preeclampsia, c-section, spontaneous pre-term birth, iron deficiency anemia) % and n with abnormal results by study arm
Trial safety - Neonatal outcomes
Time frame: Labor and delivery
Data obtained from the participant's electronic health record (small or large for gestational age, neonatal intensive care admission, jaundice, APGAR score) % and n with abnormal results by study arm
Trial Retention
Time frame: 35-37 week gestational age
n and % of women retained through the final in-person data collection with \>= 80% retained
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Female based on sex assigned at birth
- Preconception body mass index (BMI) 35.0 - 60 kg/m2
- Singleton pregnancy
- Age 18-44 years old
- 14 - \< = 20 weeks gestational age
- Fluency in English to provide consent and complete study procedures
- Ability to provide informed consent
- Cleared by study doctor and the obstetrician/mid-wife provider to participate
- Access to a smartphone to complete intervention procedures
Exclusion criteria
- Deemed medically high risk
- Multiple pregnancy (e.g., twins)
- Type 1 or 2 diabetes mellitus
- Early gestational diabetes (diagnosed at \< = to17 weeks gestational age through an oral glucose tolerance test)
- Currently eating ≤ 12 hours daily
- Autoimmune disorder (e.g., rheumatoid arthritis)
- iron deficiency anemia
- Inflammatory bowel disease
- Previous spontaneous preterm birth
- History of bariatric surgery
- Night shift work
- Currently incarcerated
- Eating disorder
Where
- Chicago, Illinois
Collaborators
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jan 23, 2026 · Source of record for eligibility and locations