Dietary and Lifestyle Interventions in Obese Pregnant Women

Study Overview
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Brief Summary
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Background: Maternal obesity is associated with higher risks of adverse maternal and fetal complications, but the effects of dietary and lifestyle interventions on gestational weight gain(GWG) and pregnancy outcomes in obese pregnant women are unclear. Objective: This study examined whether intensive dietary and lifestyle interventions initiated in the early pregnancy could decrease GWG, and prevent relevant adverse pregnancy outcomes in Chinese obese pregnant women. Design:A randomized controlled trial in obese pregnant women was performed at 6-12 weeks of gestation.The sample size was estimated using GWG reduction as the primary outcome variable. The investigators pilot study (data not published) showed the gestational weight gain was 12.73±5.97 for obese women. Assuming intervention may result in 25% (3.1825g) reduction in GWG, the estimated sample size with 90% power and type I error of 0.05 was 114 women in intervention group and 57 in control group. Adjusting for 15% refusal or loss to follow up during pregnancy, the total sample size required was 136 women in intervention group and 68 in control group(standard care group). Participants were randomly assigned to the control or the intervention group. The intervention focused on restricting energy intake combined with behavioral lifestyle modification through participation in group sessions and individual counseling. The primary outcomes were gestational weight gain (GWG) and secondary outcomes were the incidence of gestational diabetes mellitus (GDM), hypertensive disorders during pregnancy, large-for-gestational-age (LGA) infants, macrosomia and the rate of caesarian section. Hypothesis:The intensive dietary and lifestyle intervention performed from the first trimester in obese women could decrease total GWG,and perhaps improve relevant pregnancy outcomes.

Official Title
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Effects of Dietary and Lifestyle Interventions in Obese Pregnant Women From the First Trimester on Gestational Weight Gain and Pregnancy Outcomes

Conditions
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Obesity, Weight Gain, Lifestyle, Pregnancy Related

Intervention / Treatment
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* Behavioral: Dietary and lifestyle intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: gestational age between 6 and 12 weeks of gestation, pre-pregnancy≥28 (kg/m2) age ≥18 years, and a singleton pregnancy. Exclusion Criteria: patients with prediabetes and diabetes, hypertension, chronic renal disease, thyroid disorder gestational weeks ≥ 13 age <18 years multiple pregnancy uterine malformation or physical restriction that prevents exercise.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dietary and lifestyle intervention<br>Intervention group:Based on standard care,intensive dietary and lifestyle intervention was provided. Initiated from the first trimester to delivery,every 2-4 weeks follow-up | Behavioral: Dietary and lifestyle intervention<br>* participants in the intervention group were provided with an individualized dietary intake protocol. Patients received a diet of not fewer than 1500 calories per day in the first trimester and not fewer than 1800 calories per day after 13wks of gestation.<br>|
| No Intervention: Standard care group<br>Standard care group:Participants received one group session in which prenatal general dietary, nutrition guideline, physical activity and recommendation for gestational weight gain introduced by a registered dietitian in 1.5hours.Participants received their regularly scheduled visits without additional dietary and lifestyle follow-up and guidance. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gestational weight gain |  | From enrollment to delivery (28-34 weeks of gestation) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of gestational diabetes mellitus |  | From enrollment to delivery (28-34 weeks of gestation) | 
| The incidence of hypertensive disorders during pregnancy |  | From enrollment to delivery (28-34 weeks of gestation) | 
| The incidence of large-for-gestational-age infants |  | From enrollment to delivery(28-34 weeks of gestation) | 
| The incidence of macrosomia infants |  | From enrollment to delivery (28-34 weeks of gestation) | 
| The rate of caesarian section |  | From enrollment to delivery(28-34 weeks of gestation) |