Prepare randomized clinical trial: Acceptability, engagement, and lifestyle effects of a weight loss intervention beginning in pre-pregnancy.

Background: Healthier lifestyles in early pregnancy are associated with lower rates of pregnancy complications, childhood adiposity, and maternal and child cardiovascular risks. However, it is not known whether lifestyle coaching initiated prior to pregnancy can affect behavior and attitudes during pregnancy.

Methods: Three hundred and twenty six women planning pregnancy within 2 years with BMI ≥27 kg/m were randomized to a behavioral weight loss intervention or to usual care. Analyses reported here examined the intervention's impact on mid-pregnancy diet quality and activity levels; program acceptability; and effects of pregnancy on intervention engagement.

Results: One hundred and sixty eight participants experienced pregnancy during the study (intervention: 91; usual care: 77). From randomization to mid-pregnancy, participants who received the intervention had larger increases in fruit intake than usual care participants (+0.67 vs. +0.06 cups;  = 0.02) and engaged in more vigorous-intensity activity (3.9 [5.5] vs. 1.2 [3.0] Met-hr/week  = 0.002) and sports/exercise (17.0 [14.1] vs. 11.0 [9.5] Met-hr/week;  = 0.03); the groups also differed in changes in sedentary time (-4.9 [15.0] vs. +0.5 [7.6] Met-hr/week;  = 0.02). Intervention satisfaction was high (>80%), and experiencing pregnancy during the intervention was associated with higher engagement.

Conclusion: A coaching-based intervention beginning in pre-pregnancy successfully helped women attain healthier diet and exercise habits in mid-pregnancy.

Clinical Trials Registration: Registered with ClinicalTrials.gov, NCT02346162, first registered on January 26, 2015, before date of initial participant enrollment (May 2015), https://clinicaltrials.gov/ct2/show/NCT02346162.