Obesity-fertility Cohort Study: Protocol for the Assessment of Children Aged 6-12 Years and Their Mothers

Follow-up of Children Born From a Randomized Controlled Trial Assessing a Preconception Lifestyle Intervention in Women With Obesity and Infertility

Maternal preconception obesity and adverse gestational metabolic health increase the risk of childhood obesity in offspring. A group of investigators from Université de Sherbrooke therefore developed a lifestyle intervention starting during preconception in women with obesity and infertility, which was evaluated with the Obesity-Fertility randomized controlled trial (RCT). The present study will assess children who were born in the Obesity-Fertility RCT and are now aged 6-10 years old. The objective of this study is to evaluate the effect of a lifestyle intervention during preconception and pregnancy on adiposity and cardiometabolic parameters in offspring compared to those born to mothers who did not have access to the lifestyle intervention. The hypothesis being that, at the age of 6-10 years old, children born to mothers who were in the intervention group have more favorable measurements of body composition and certain metabolic and/or inflammatory blood markers than those born to control mothers.

Participants in the Obesity-Fertility RCT were women with obesity and infertility recruited at the Centre hospitalier universitaire de Sherbrooke (CHUS) fertility clinic. They were randomly allocated to the control group, which followed standard care, or to the intervention group, which received a lifestyle intervention alone for 6 months, and then in combination with fertility treatments. Those who have given birth to a single child will be invited to participate in this follow-up study with their child. During the research visit, medical history, anthropometry, body composition, lifestyle, physical fitness level, and blood or saliva markers of cardiometabolic health will be assessed for both mothers and children.

This study will provide new evidence on the impact of targeting lifestyle habits during preconception on the health of children and their mothers 6-10 years later; and the potential of such interventions to counteract the intergenerational transmission of obesity.

Study Overview

• Status: Completed
• Conditions: Obesity, Childhood; Lifestyle Intervention; Preconception Care
• Intervention / Treatment: Behavioral: Fit-for-Fertility program

Detailed Description

INTRODUCTION: Maternal preconception obesity and adverse gestational metabolic health increase the risk of childhood obesity in offspring. A group of investigators from Université de Sherbrooke therefore developed a lifestyle intervention starting during preconception in women with obesity and infertility, which was evaluated with the Obesity-Fertility randomized controlled trial (RCT) registered at ClinicalTrials.gov (NCT01483612). The present study will assess children who were born in the Obesity-Fertility RCT and are now aged 6-10 years old. The objective of this study is to evaluate the effect of a lifestyle intervention during preconception and pregnancy on adiposity and cardiometabolic parameters in offspring compared to those born to mothers who did not have access to the lifestyle intervention.

METHODS AND ANALYSIS: Participants in the Obesity-Fertility RCT were women with obesity and infertility recruited at the CHUS fertility clinic between January 2012 and August 2018. They were randomly allocated to the control group, which followed standard care, or to the intervention group, which received a lifestyle intervention alone for 6 months, and then in combination with fertility treatments. Those who have given birth to a single child will be invited to participate in this follow-up study with their child. This study will take place from October 2023 to September 2024, when the child will be 6-10 years old. During the research visit, medical history, anthropometry, body composition, lifestyle, physical fitness level, and blood or saliva markers of cardiometabolic health will be assessed for both mothers and children. Of the 130 women who participated in the Obesity-Fertility RCT, 53 mother-child dyads are potentially eligible for this follow-up study. Comparisons between groups will be performed using appropriate unpaired tests and adjusted for potential confounders using multiple regression models.

ETHICS AND DISSEMINATION: The study has been approved by the Institutional Research Ethics Review Boards of the CHUS. The results will be widely disseminated to the scientific community as well as to relevant health professionals and the general public.

IMPACT: This study will provide new evidence on the impact of targeting lifestyle habits during preconception on the health of children and their mothers 6-10 years later; and the potential of such interventions to counteract the intergenerational transmission of obesity.

• Study Type: Observational
• Enrollment (Actual): 35

Contacts and Locations

Study Locations

• Canada
  • Quebec
    • Sherbrooke, Quebec, Canada, J1H 5N4
      • Centre Hospitalier Universitaire de Sherbrooke

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Children born from mothers who participated in the Obesity-Fertility study. Those mother were recruited between 2012 and 2018 at the fertility clinic of the Centre hospitalier universitaire de Sherbrooke. To be included in the study, they had to be aged between 18 and 40 years and living with infertility and obesity, or overweight if they had polycystic ovary syndrome (PCOS). Women were excluded if they had undergone or were planning bariatric surgery, or if natural conception was impossible or unlikely (such as both fallopian tubes blocked or severe male factor).

Description

Inclusion Criteria:

• Offsprings of women who were randomized in the Obesity-Fertility study known to have been conceived within 18 months following randomization of their mothers from a singleton pregnancy.

Exclusion Criteria:

• Children having a disease or taking a medication that has a major impact on weight, anthropometry, lifestyle habits or functional capacity (e.g., congenital heart disease, functional disability, severe asthma, regular use of glucocorticoids, etc.).

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Intervention; Children born from mothers who were allocated to the intervention group in the Obesity-Fertility study.	Behavioral: Fit-for-Fertility program; Women in the intervention group had to delay fertility treatments for 6 months and were offered the interdisciplinary lifestyle intervention, which was provided for a maximum of 18 months or until the end of a pregnancy that occurred. The lifestyle intervention consisted of individual meetings with a dietitian and a kinesiologist trained in motivational interviewing, combined with 12 educational group sessions during the first 6 months. Details of the lifestyle intervention are presented in the previously published protocol (Duval et al., 2015).
Control; Children born from mothers who were allocated to the control group in the Obesity-Fertility study. Participants in the control group received standard care from the fertility clinic without delay.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anthropometrics - BMI z score (child)	BMI Z-score adjusted for age and sex calculated according to World Health Organization reference values (AnthroPlus software, version 1.0, last updated September 17, 2014)	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anthropometrics - Waist circumference	Measured at the highest point of the iliac crests according to the National Institutes of Health (NIH) method to the nearest 0.1 cm with a flexible tape	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Anthropometrics - Waist-to-height ratio (child)	Calculated from the child's waist circumference (cm) and height (cm).	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Body composition measured by dual-energy X-ray absorptiometry	Fat and lean body mass, ratio	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Lifestyle - Self-reported physical activity by GSLTPAQ (child)	Godin-Shephard Leisure-Time Physical Activity Questionnaire (GSLTPAQ) measures frequency and intensity of physical activity practiced by the child during the past seven days	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Lifestyle - Self-reported physical activity level (mother)	Questionnaire adapted from the 2009 Canadian Community Health Survey of Statistics Canada	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Lifestyle - Number of steps per day measured by Fitbit (child)	Fitbit wristband monitor worn for seven consecutive days	Once, over a one-week period, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Lifestyle - Minutes per day of physical activity measured by Fitbit (child)	Fitbit wristband monitor worn for seven consecutive days	Once, over a one-week period, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Lifestyle - Dietary behaviours by CTFEQr17 (child)	French version of the Child Three-Factor Eating Questionnaire (CTFEQr17)	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Lifestyle - Food intake (child)	Online 24-hour dietary recall survey developed by Laval University	Three dietary recall, over a period of four weeks, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Lifestyle - Eating habits (mother)	Questionnaire adapted from the 2009 Canadian Community Health Survey of Statistics Canada	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Physical fitness level - Cardiorespiratory fitness (child)	Maximal exertion test using the McMaster protocol	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Physical fitness level - Grip strength (child)	Hand dynamometer (kg)	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Physical fitness level - Functional capacity (mother)	Six-minute walk test	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - Systolic and diastolic blood pressure	Arm cuff appropriate for the arm size (mmHg)	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - Systolic and diastolic blood pressure Z-scores (child)	Age-, sex- and height-adjusted Z-scores from normative tables from the American Academy of Pediatrics Pediatric Reference Guidelines	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - Heart rate	Arm cuff appropriate for the arm size (bpm)	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - Total cholesterol (TC)	Fasting levels	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - Triglycerides	Fasting levels	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - High-density lipoprotein (HDL) cholesterol	Fasting levels	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - Low-density lipoprotein (LDL) cholesterol	Fasting levels	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.
Cardiometabolic health - Cholesterol ratio	Fasting levels of TC divide by fasting levels of HDL	Once, between October 2023 and September 2024 (11 months), which is 6 to 10 years after the child's birth.

Collaborators and Investigators

• Sponsor: Université de Sherbrooke
• Investigators: Principal Investigator: Jean-Patrice Baillargeon, MD, Université de Sherbrooke

Publications and helpful links

General Publications

• Duval K, Langlois MF, Carranza-Mamane B, Pesant MH, Hivert MF, Poder TG, Lavoie HB, Ainmelk Y, St-Cyr Tribble D, Laredo S, Greenblatt E, Sagle M, Waddell G, Belisle S, Riverin D, Jean-Denis F, Belan M, Baillargeon JP. The Obesity-Fertility Protocol: a randomized controlled trial assessing clinical outcomes and costs of a transferable interdisciplinary lifestyle intervention, before and during pregnancy, in obese infertile women. BMC Obes. 2015 Dec 1;2:47. doi: 10.1186/s40608-015-0077-x. eCollection 2015.
• Thibodeau A, Jean-Denis F, Harnois-Leblanc S, Perron P, Mathieu ME, Dallaire F, Morisset AS, Brochu M, Baillargeon JP. Obesity-fertility cohort study: protocol for the assessment of children aged 6-12 years and their mothers. BMJ Open. 2025 Apr 17;15(4):e091140. doi: 10.1136/bmjopen-2024-091140.

Study record dates

Study Major Dates

• Study Start (Actual): November 13, 2023
• Primary Completion (Actual): February 21, 2025
• Study Completion (Actual): June 23, 2025

Study Registration Dates

• First Submitted: April 23, 2024
• First Submitted That Met QC Criteria: May 2, 2024
• First Posted (Actual): May 7, 2024

Study Record Updates

• Last Update Posted (Actual): May 6, 2026
• Last Update Submitted That Met QC Criteria: April 29, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Obesity; Fetal programming; Healthy lifestyle; Maternal obesity; Preconception care
• Additional Relevant MeSH Terms: Urogenital Diseases; Nutrition Disorders; Female Urogenital Diseases and Pregnancy Complications; Overnutrition; Body Weight; Pregnancy Complications; Overweight; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Obesity; Pediatric Obesity; Pregnancy in Obesity
• Other Study ID Numbers: 2024-5150

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