Evidence-based recommendations for energy intake in pregnant women with obesity.

BACKGROUND: In women with obesity, excess gestational weight gain (≥270 g/week) occurs in two out of three pregnancies and contributes to metabolic impairments in both mother and baby. To improve obstetrical care, objectively assessed information on energy balance is urgently needed. The objective of this study was to characterize determinants of gestational weight gain in women with obesity. METHODS: This was a prospective, observational study of pregnant women with obesity. The primary outcome was energy intake calculated by the energy intake-balance method. Energy expenditure was measured by doubly-labeled water and whole-room indirect calorimetry and body composition as 3-compartment model by air displacement plethysmography and isotope dilution in early (13-16 weeks) and late pregnancy (35-37 weeks). RESULTS: In pregnant women with obesity (n=54), recommended weight gain (n=8, 15%) during the second and third trimesters was achieved when energy intake was 125±52 kcal/d less than energy expenditure. In contrast, women with excess weight gain (67%) consumed 186±29 kcal/d more than they expended (P<0.001). Energy balance affected maternal adiposity (recommended: -2.5±0.8 kg fat mass, excess: +2.2±0.5, inadequate: -4.5±0.5, P<0.001), but not fetal growth. Weight gain was not related to demographics, activity, metabolic biomarkers, or diet quality. We estimated that energy intake requirements for recommended weight gain during the second and third trimesters were not increased as compared to energy requirements early in pregnancy (34±53 kcal/d, P=0.83). CONCLUSIONS: We here provide the first evidence-based recommendations for energy intake in pregnant women with obesity. Contrary to current recommendations, energy intake should not exceed energy expenditure. FUNDING: This study was funded by the National Institutes of Health (R01DK099175; Redman, U54GM104940 and P30DK072476; Core support). TRIAL REGISTRATION: clinicaltrials.gov: NCT01954342.

Energy Expenditure in Pregnant Women with Obesity Does Not Support Energy Intake Recommendations.

OBJECTIVE: This study aimed to identify factors that may predispose women to excess gestational weight gain (GWG). METHODS: Seventy-two healthy women with obesity (30 class I, 24 class II, 18 class III) expecting a singleton pregnancy were studied at 13 to 16 weeks gestation. Energy expenditure (EE) was measured during sleep (SleepEE, average EE from 0200-0500 hours) in a whole-room calorimeter, and total daily EE (TDEE) over 7 days using doubly labeled water. Glucose, insulin, thyroid hormones, and catecholamines were measured. RESULTS: Body composition explained 70% variability in SleepEE, and SleepEE accounted for 67% to 73% of TDEE. Though there was no evidence of consistent low metabolism, there was considerable variability. Low SleepEE was associated with insulin resistance and low triiodothyronine concentrations (both P = 0.01). Physical activity level was 1.47 ± 0.02. For women with SleepEE within 100 kcal/d of their predicted EE, TDEE was significantly less than the estimate (2,530 ± 91 vs. 2,939 kcal/d; P < 0.001) provided from the most recent gestational energy requirement model. CONCLUSIONS: Pregnant women with obesity are inactive, possibly predisposing them to excess GWG. Current energy requirement models overestimate activity and may promote excess GWG in women with obesity. Furthermore, the observed large interindividual variability in basal metabolism may be important to consider when assessing the risk for excess GWG.

Food Photography Is Not an Accurate Measure of Energy Intake in Obese, Pregnant Women.

Background: To improve weight management in pregnant women, there is a need to deliver specific, data-based recommendations on energy intake. Objective: This cross-sectional study evaluated the accuracy of an electronic reporting method to measure daily energy intake in pregnant women compared with total daily energy expenditure (TDEE). Methods: Twenty-three obese [mean ± SEM body mass index (kg/m2): 36.9 ± 1.3] pregnant women (aged 28.3 ±1.1 y) used a smartphone application to capture images of their food selection and plate waste in free-living conditions for ≥6 d in early (13-16 wk) and late (35-37 wk) pregnancy. Energy intake was evaluated by the smartphone application SmartIntake and compared with simultaneous assessment of TDEE obtained by doubly labeled water. Accuracy was defined as reported energy intake compared with TDEE (percentage of TDEE). Ecological momentary assessment prompts were used to enhance data reporting. Two-one-sided t tests for the 2 methods were used to assess equivalency, which was considered significant when accuracy was >80%. Results: Energy intake reported by the SmartIntake application was 63.4% ± 2.3% of TDEE measured by doubly labeled water (P = 1.00). Energy intake reported as snacks accounted for 17% ± 2% of reported energy intake. Participants who used their own phones compared with participants who used borrowed phones captured more images (P = 0.04) and had higher accuracy (73% ± 3% compared with 60% ± 3% of TDEE; P = 0.01). Reported energy intake as snacks was significantly associated with the accuracy of SmartIntake (P = 0.03). To improve data quality, excluding erroneous days of likely underreporting (<60% TDEE) improved the accuracy of SmartIntake, yet this was not equivalent to TDEE (-22% ± 1% of TDEE; P = 1.00). Conclusions: Energy intake in obese, pregnant women obtained with the use of an electronic reporting method (SmartIntake) does not accurately estimate energy intake compared with doubly labeled water. However, accuracy improves by applying criteria to eliminate erroneous data. Further evaluation of electronic reporting in this population is needed to improve compliance, specifically for reporting frequent intake of small meals. This trial was registered at www.clinicaltrials.gov as NCT01954342.

Strategies for Successful Recruitment of Pregnant Patients Into Clinical Trials.

Clinical research in the pregnant population allows for delivery of quality, evidence-based care in obstetrics. However, in recent years, the field of obstetrics has faced severe challenges in the recruitment of the pregnant population into clinical trials, a struggle also shared by several other medical disciplines. We candidly describe our failure to recruit a healthy population of overweight and obese pregnant women in their first trimester. We were then able to glean unsuccessful and successful recruitment approaches and improve our recruitment effort by autopsy of failed strategies and with guidance from a survey disseminated to improve our understanding of community feelings about participating in research while pregnant. These "lessons learned" taught us that active recruitment within this population is a necessity; that is, direct (face-to-face discussions at obstetric appointments) compared with indirect (flyers and general emails) modalities and that prenatal care provider support of the proposed research study is vital to a patient's willingness to participate. By implementation of "lessons learned," we describe how we successfully recruited a similar pregnant population 1 year later. The Clinical Trials related to our article are as follows: 1) Expecting Success: NCT01610752, https://clinicaltrials.gov/ct2/show/NCT01610752; 2) MomEE: NCT01954342, https://clinicaltrials.gov/ct2/show/NCT01954342; and 3) Participate While Pregnant Survey: NCT02699632, https://clinicaltrials.gov/ct2/show/NCT02699632.