A Weight Maintenance Program Promoting Fat Loss in Pregnancy in Women With Obesity (Healthy Mamas)

The aims of this randomized controlled trial are to determine the effects of a lifestyle program that supports weight maintenance and fat mass loss during pregnancy in women with obesity on changes in 1) maternal weight, fat mass, and cardiometabolic risk factors; 2) safety measures, including fetal and neonatal growth; 3) the mediators and moderators of the fat mass loss intervention and 4) the effects gestational fat mass loss has on reducing incidence of adverse obstetrical outcomes, including non-elective cesarean delivery, gestational diabetes, hypertension, and pre-eclampsia.

Study Overview

• Status: Completed
• Conditions: Obesity; Gestational Weight Gain
• Intervention / Treatment: Behavioral: Weight Maintenance Group

Detailed Description

One hundred pregnant women with obesity who are otherwise healthy will be studied from early pregnancy until approximately 2 weeks postpartum. Major assessments will occur at baseline (13-16 weeks gestation), 27-29 weeks gestation, 35-37 weeks gestation, and approximately 2 weeks postpartum. Safety assessments will be collected every 4 weeks after enrollment. Participants will be randomized within site (approximately 50 individuals at Pennington Biomedical Research Center and approximately 50 individuals at California Polytechnic University) and obesity to either: Provider Directed Group or Weight Maintenance Group.

• Study Type: Interventional
• Enrollment (Actual): 100
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • California
    • San Luis Obispo, California, United States, 93407
      • California Polytechnic State University
  • Louisiana
    • Baton Rouge, Louisiana, United States, 70808
      • Pennington Biomedical Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Are pregnant less than or equal to 15 weeks gestation at screening
• Have a body mass index between 31.0 and 55.0 inclusive
• Have a confirmed viable singleton gestation
• Willing to receive randomization to either group
• Willing and able to eat the study foods
• Willing to enroll infant for study measurements after birth
• Receive clearance from the prenatal care provider for participation

Exclusion Criteria:

• Smoking, drug, or alcohol use
• Have a known fetal anomaly
• Have a non-pregnancy related illness
• Have pre-existing diabetes
• Have pre-existing hypertension
• Have severe anemia
• Have current mental health issue or eating disorder
• Short inter-pregnancy interval (<6 months since last pregnancy)
• Use of assisted reproductive technology
• Use of medications with known effects on body weight including over the counter medications and supplements for weight loss
• History of pre-eclampsia, prior small for gestational age infant, bariatric surgery
• Planning to move out of the area in the next 12 months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Weight Maintenance Group; Individuals in this group will receive all aspects of the Provider Directed Group plus a comprehensive behavioral fat mass loss intervention with food provision. Individuals in this group will be provided foods to eat to support weight maintenance and loss of body fat throughout pregnancy. They will be asked to attend two behavioral counseling sessions at the beginning of the study to help learn the program and set goals. They will return for brief visits with a lifestyle counselor every two weeks until 20 weeks gestation and at least once a month until delivery. Individuals will be provided a scale to help keep track of weight during pregnancy.	Behavioral: Weight Maintenance Group; The behavioral program is rooted in social learning theory and based on our existing prenatal intervention but with full food provision to ensure gestational fat mass loss is steady and closely supervised. Brief counseling sessions are designed to review self-monitoring records, reinforce adherence to the structured food provision program, problem-solve barriers, and provide additional support. Individuals will be provided with a structured meal plan designed to promote 25% calorie restriction during the second trimester followed by eucaloric intake during the 3rd trimester. Participants will be provided three meals and two snacks on 7 days at no cost.
No Intervention: Provider Directed Group; Individuals in this group will receive what is standard practice by their prenatal care providers during pregnancy. In addition, individuals in this group will be asked to attend a brief session at the time of randomization to familiarize with the study and what is expected. They will also be provided with materials describing healthy behaviors in pregnancy.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body weight	Body weight will be measured using a calibrated electrical scale with participants wearing a hospital gown and underwear.	From study entry to approximately 2 weeks postpartum

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fat mass	Fat mass will be assessed via a 3-compartment model in which fat mass is calculated from body weight, body density measured by the BODPOD, and total body water measured by deuterium dilution.	From study entry to approximately 2 weeks postpartum

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total body water	Total body water is assessed by deuterium dilution.	From study entry to approximately 2 weeks postpartum
Fat-free mass	Fat-free mass will be calculated as the subtraction of fat mass from total body weight.	From study entry to approximately 2 weeks postpartum
Fetal weight	Fetal weight is measured by ultrasound and estimated by Hadlock formula.	From 19-22 weeks gestation to 39-42 weeks gestation
Infant body composition	Infant body composition will be assessed via a 3-compartment model which includes body weight, PEAPOD, and dual-energy x-ray absorptiometry.	Approximately 2 weeks old
Dietary intake	Dietary intake is assessed by automated self-administered 24-hour dietary assessment tool (ASA-24).	From study entry to 35-37 weeks gestation
Metabolic syndrome score	Metabolic syndrome score will be determined using measured blood pressure and waist circumference, and triglycerides, high density lipoprotein cholesterol, and glucose.	From study entry to approximately 2 weeks postpartum
Perinatal outcomes	All perinatal outcomes (ie non-elective cesarean delivery, gestational diabetes, hypertension, pre-eclampsia) will be obtained by prenatal and delivery medical chart abstraction.	From study entry to approximately 2 weeks postpartum
Time Spent in Physical activity	Physical activity (amount of time spent in physical activity) is assessed by activPAL activity device over a period of 5-7 days.	From study entry to 35-37 weeks gestation

Collaborators and Investigators

• Sponsor: Pennington Biomedical Research Center
• Collaborators: National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK); Oregon Health and Science University; California Polytechnic State University-San Luis Obispo
• Investigators: Principal Investigator: Leanne M Redman, Ph.D., Pennington Biomedical Research Center

Publications and helpful links

General Publications

• Redman LM, Phelan S, Apolzan JW, Beyl RA, Altazan AD, Dickey MS, Simeon E, Flanagan EW, Cabre HE, Sparks JR, Kebbe M, Caughey AB, Valent AM, Hsia DS, Yin E, Keadle SK. Protocol for a randomised controlled trial of a weight maintenance intervention to promote fat loss in pregnant individuals with obesity. BMJ Open. 2025 Feb 25;15(2):e095804. doi: 10.1136/bmjopen-2024-095804.

Study record dates

Study Major Dates

• Study Start (Actual): March 10, 2021
• Primary Completion (Actual): November 24, 2025
• Study Completion (Actual): November 24, 2025

Study Registration Dates

• First Submitted: January 26, 2021
• First Submitted That Met QC Criteria: January 26, 2021
• First Posted (Actual): February 1, 2021

Study Record Updates

• Last Update Posted (Actual): May 22, 2026
• Last Update Submitted That Met QC Criteria: May 20, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Pregnancy; Body Composition
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Body Weight Changes; Overweight; Weight Gain; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Gestational Weight Gain; Obesity
• Other Study ID Numbers: PBRC 2019-070; 1R01DK124806-01 (U.S. NIH Grant/Contract)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No