Kristina Renault

The Treatment of Obese Pregnant Women (TOP) study: a randomized controlled trial of the effect of physical activity intervention assessed by pedometer with or without dietary intervention in obese pregnant women

OBJECTIVE The objective of the study was to assess physical activity intervention assessed by a pedometer with or without dietary intervention on gestational weight gain (GWG) in obese pregnant women by comparing with a control group. STUDY DESIGN This study was a randomized controlled trial of 425 obese pregnant women comparing 3 groups: (1) PA plus D, physical activity and dietary intervention (n = 142); (2) PA, physical activity intervention (n = 142); and (3) C, a control group receiving standard care (n = 141). All participants routinely in gestational weeks 11-14 had an initial dietary counseling session and were advised to limit GWG to less than 5 kg. Physical activity intervention included encouragement to increase physical activity, aiming at a daily step count of 11,000, monitored by pedometer assessment on 7 consecutive days every 4 weeks. Dietary intervention included follow-up on a hypocaloric Mediterranean-style diet. Instruction was given by a dietician every 2 weeks. The primary outcome measure was GWG, and the secondary outcome measures were complications of pregnancy and delivery and neonatal outcome. RESULTS The study was completed by 389 patients (92%). Median values of GWG (ranges) were lower in each of the intervention groups (PA plus D, 8.6 [-9.6 to 34.1] kg, and group PA, 9.4 [-3.4 to 28.2] kg) compared with the control group (10.9 [-4.4 to 28.7] kg [PA+D vs C]; P = .01; PA vs C; P = .042). No significant difference was found between the 2 intervention groups. In a multivariate analysis, physical activity intervention decreased GWG by a mean of 1.38 kg (P = .040). The Institute of Medicines recommendations for GWG were more frequently followed in the intervention groups. CONCLUSION Physical activity intervention assessed by pedometer with or without dietary follow-up reduced GWG compared with controls in obese pregnant women.

Physical activity during pregnancy in obese and normal-weight women as assessed by pedometer

Objective. To compare physical activity as assessed by a pedometer in obese and normal‐weight pregnant women at different gestational ages. To evaluate the use of a pedometer in pregnancy. Design. Cross‐sectional study. Setting. Department of obstetrics and gynecology in a university hospital in Copenhagen. Population. 338 pregnant women, 175 normal‐weight women with body mass index (BMI) 20–25 kg/m2 and 163 obese women with BMI ≥ 30 kg/m2. Methods. Physical activity was assessed by a pedometer (Yamax Digiwalker SW‐700/701) on seven consecutive days in six different groups: normal‐weight or obese at gestational ages 11–13, 18–22, and 36–38, and expressed as median number of daily steps during a whole week, working days, and weekends. Main outcome measures. Relation between BMI and physical activity during pregnancy and compliance with wearing the pedometer. Results. Noncompliance was more frequent in obese than in normal‐weight women (19 vs. 10%, p < 0.001). Physical activity was lower in obese women at all gestational ages (6,482, 7,446, 4,626 steps/day in obese vs. 7,558, 8,865, 6,289 steps/day in normal‐weight, p < 0.05–0.11). The greatest difference between obese and normal‐weight women was seen during weekends. The level of physical activity was higher in both groups at mid‐gestation than during earlier and later gestational ages. Conclusion. Physical activity in pregnant women can be assessed by the pedometer and the method was well accepted by the women; however, the compliance was lower in the obese. The level of physical activity differs between different gestational groups and is lower in obese than in normal‐weight women, especially during leisure time.

Effects of antenatal diet and physical activity on maternal and fetal outcomes: Individual patient data meta-analysis and health economic evaluation

BACKGROUND Diet- and physical activity-based interventions in pregnancy have the potential to alter maternal and child outcomes. OBJECTIVES To assess whether or not the effects of diet and lifestyle interventions vary in subgroups of women, based on maternal body mass index (BMI), age, parity, Caucasian ethnicity and underlying medical condition(s), by undertaking an individual patient data (IPD) meta-analysis. We also evaluated the association of gestational weight gain (GWG) with adverse pregnancy outcomes and assessed the cost-effectiveness of the interventions. DATA SOURCES MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects and Health Technology Assessment database were searched from October 2013 to March 2015 (to update a previous search). REVIEW METHODS Researchers from the International Weight Management in Pregnancy Collaborative Network shared the primary data. For each intervention type and outcome, we performed a two-step IPD random-effects meta-analysis, for all women (except underweight) combined and for each subgroup of interest, to obtain summary estimates of effects and 95% confidence intervals (CIs), and synthesised the differences in effects between subgroups. In the first stage, we fitted a linear regression adjusted for baseline (for continuous outcomes) or a logistic regression model (for binary outcomes) in each study separately; estimates were combined across studies using random-effects meta-analysis models. We quantified the relationship between weight gain and complications, and undertook a decision-analytic model-based economic evaluation to assess the cost-effectiveness of the interventions. RESULTS Diet and lifestyle interventions reduced GWG by an average of 0.70 kg (95% CI -0.92 to -0.48 kg; 33 studies, 9320 women). The effects on composite maternal outcome [summary odds ratio (OR) 0.90, 95% CI 0.79 to 1.03; 24 studies, 8852 women] and composite fetal/neonatal outcome (summary OR 0.94, 95% CI 0.83 to 1.08; 18 studies, 7981 women) were not significant. The effect did not vary with baseline BMI, age, ethnicity, parity or underlying medical conditions for GWG, and composite maternal and fetal outcomes. Lifestyle interventions reduce Caesarean sections (OR 0.91, 95% CI 0.83 to 0.99), but not other individual maternal outcomes such as gestational diabetes mellitus (OR 0.89, 95% CI 0.72 to 1.10), pre-eclampsia or pregnancy-induced hypertension (OR 0.95, 95% CI 0.78 to 1.16) and preterm birth (OR 0.94, 95% CI 0.78 to 1.13). There was no significant effect on fetal outcomes. The interventions were not cost-effective. GWG, including adherence to the Institute of Medicine-recommended targets, was not associated with a reduction in complications. Predictors of GWG were maternal age (summary estimate -0.10 kg, 95% CI -0.14 to -0.06 kg) and multiparity (summary estimate -0.73 kg, 95% CI -1.24 to -0.23 kg). LIMITATIONS The findings were limited by the lack of standardisation in the components of intervention, residual heterogeneity in effects across studies for most analyses and the unavailability of IPD in some studies. CONCLUSION Diet and lifestyle interventions in pregnancy are clinically effective in reducing GWG irrespective of risk factors, with no effects on composite maternal and fetal outcomes. FUTURE WORK The differential effects of lifestyle interventions on individual pregnancy outcomes need evaluation. STUDY REGISTRATION This study is registered as PROSPERO CRD42013003804. FUNDING The National Institute for Health Research Health Technology Assessment programme.

Dietary interventions in overweight and obese pregnant women: a systematic review of the content, delivery, and outcomes of randomized controlled trials.

CONTEXT Interventions targeting maternal obesity are a healthcare and public health priority. OBJECTIVE The objective of this review was to evaluate the adequacy and effectiveness of the methodological designs implemented in dietary intervention trials for obesity in pregnancy. DATA SOURCES A systematic review of the literature, consistent with PRISMA guidelines, was performed as part of the International Weight Management in Pregnancy collaboration. STUDY SELECTION Thirteen randomized controlled trials, which aimed to modify diet and physical activity in overweight and obese pregnant women, were identified. DATA SYNTHESIS There was significant variability in the content, delivery, and dietary assessment methods of the dietary interventions examined. A number of studies demonstrated improved dietary behavior in response to diet and/or lifestyle interventions. Nine studies reduced gestational weight gain. CONCLUSION This review reveals large methodological variability in dietary interventions to control gestational weight gain and improve clinical outcomes in overweight and obese pregnant women. This lack of consensus limits the ability to develop clinical guidelines and apply the evidence in clinical practice.

Telephone-based support prolongs breastfeeding duration in obese women: a randomized trial

BACKGROUND Obese women often have difficulties breastfeeding. OBJECTIVE We evaluated whether telephone-based support could increase the duration of breastfeeding in obese women and, thereby, reduce offspring growth. DESIGN We recruited 226 dyads of obese mothers and their singleton, healthy, term infants. The women were randomly assigned to 6 mo of breastfeeding support or standard care controls. At 6 mo, there were 207 dyads in the study; 105 dyads received support, and 102 dyads were control subjects. One International Board Certified Lactation Consultant carried out the intervention, which was based on structured interviews and consisted of encouraging telephone calls. RESULTS The support group breastfed exclusively for a median of 120 d (25th-75th percentiles: 14-142 d) compared with 41 d (3-133 d) for control subjects (P = 0.003). Any breastfeeding was maintained for a median of 184 d (92-185 d) for the support group compared with 108 d (16-185 d) for control subjects (P = 0.002). Support increased the adjusted ORs for exclusive breastfeeding at 3 mo and the ratios for partial breastfeeding at 6 mo to 2.45 (95% CI: 1.36, 4.41; P = 0.003) and 2.25 (95% CI: 1.24, 4.08; P = 0.008, respectively). Although the duration of exclusive breastfeeding was inversely associated with infant weight (β = -4.39 g/d; 95% CI: -0.66, -8.11 g/d; P = 0.021) and infant length at 6 mo (β = -0. 012 cm/d; 95% CI: -0.004, -0.02 cm/d; P = 0.004), the breastfeeding support did not achieve a significant effect on infant growth at 6 mo (n = 192). CONCLUSIONS Telephone-based advisory support was very effective in prolonging breastfeeding in obese mothers who often terminate the breastfeeding of their infants prematurely. A longer duration of breastfeeding may decrease risk of noncommunicable diseases in these infants. This trial was registered at clinicaltrials.gov as NCT01235663.

Newborn regional body composition is influenced by maternal obesity, gestational weight gain and the birthweight standard score

This study investigated whether newborn body composition is influenced by prepregnancy obesity and gestational weight gain (GWG) and explored any associations between body composition and birthweight standard score (z‐score), categorised by size for gestational age.

Study protocol: differential effects of diet and physical activity based interventions in pregnancy on maternal and fetal outcomes-individual patient data (IPD) meta-analysis and health economic evaluation

BackgroundPregnant women who gain excess weight are at risk of complications during pregnancy and in the long term. Interventions based on diet and physical activity minimise gestational weight gain with varied effect on clinical outcomes. The effect of interventions on varied groups of women based on body mass index, age, ethnicity, socioeconomic status, parity, and underlying medical conditions is not clear. Our individual patient data (IPD) meta-analysis of randomised trials will assess the differential effect of diet- and physical activity-based interventions on maternal weight gain and pregnancy outcomes in clinically relevant subgroups of women.Methods/designRandomised trials on diet and physical activity in pregnancy will be identified by searching the following databases: MEDLINE, EMBASE, BIOSIS, LILACS, Pascal, Science Citation Index, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews of Effects, and Health Technology Assessment Database. Primary researchers of the identified trials are invited to join the International Weight Management in Pregnancy Collaborative Network and share their individual patient data. We will reanalyse each study separately and confirm the findings with the original authors. Then, for each intervention type and outcome, we will perform as appropriate either a one-step or a two-step IPD meta-analysis to obtain summary estimates of effects and 95% confidence intervals, for all women combined and for each subgroup of interest. The primary outcomes are gestational weight gain and composite adverse maternal and fetal outcomes. The difference in effects between subgroups will be estimated and between-study heterogeneity suitably quantified and explored. The potential for publication bias and availability bias in the IPD obtained will be investigated. We will conduct a model-based economic evaluation to assess the cost effectiveness of the interventions to manage weight gain in pregnancy and undertake a value of information analysis to inform future research.Systematic review registrationPROSPERO 2013:CRD42013003804

Effect of diet and physical activity based interventions in pregnancy on gestational weight gain and pregnancy outcomes: meta-analysis of individual participant data from randomised trials

Abstract Objective To synthesise the evidence on the overall and differential effects of interventions based on diet and physical activity during pregnancy, primarily on gestational weight gain and maternal and offspring composite outcomes, according to women’s body mass index, age, parity, ethnicity, and pre-existing medical condition; and secondarily on individual complications. Design Systematic review and meta-analysis of individual participant data (IPD). Data sources Major electronic databases from inception to February 2017 without language restrictions. Eligibility criteria for selecting studies Randomised trials on diet and physical activity based interventions in pregnancy. Data synthesis Statistical models accounted for clustering of participants within trials and heterogeneity across trials leading to summary mean differences or odds ratios with 95% confidence intervals for the effects overall, and in subgroups (interactions). Results IPD were obtained from 36 randomised trials (12 526 women). Less weight gain occurred in the intervention group than control group (mean difference −0.70 kg, 95% confidence interval −0.92 to −0.48 kg, I2=14.1%; 33 studies, 9320 women). Although summary effect estimates favoured the intervention, the reductions in maternal (odds ratio 0.90, 95% confidence interval 0.79 to 1.03, I2=26.7%; 24 studies, 8852 women) and offspring (0.94, 0.83 to 1.08, I2=0%; 18 studies, 7981 women) composite outcomes were not statistically significant. No evidence was found of differential intervention effects across subgroups, for either gestational weight gain or composite outcomes. There was strong evidence that interventions reduced the odds of caesarean section (0.91, 0.83 to 0.99, I2=0%; 32 studies, 11 410 women), but not for other individual complications in IPD meta-analysis. When IPD were supplemented with study level data from studies that did not provide IPD, the overall effect was similar, with stronger evidence of benefit for gestational diabetes (0.76, 0.65 to 0.89, I2=36.8%; 59 studies, 16 885 women). Conclusion Diet and physical activity based interventions during pregnancy reduce gestational weight gain and lower the odds of caesarean section. There is no evidence that effects differ across subgroups of women.

Intake of carbohydrates during pregnancy in obese women is associated with fat mass in the newborn offspring

BACKGROUND Transmission of obesity across generations is of concern. Offspring of obese women have short- and long-term increased morbidities. A high intake of carbohydrate during pregnancy combined with impaired glucose tolerance is postulated to result in high birth weight, which is linked to subsequent metabolic disease. OBJECTIVE The objective was to examine the association between carbohydrate intake in obese pregnant women and their offsprings body composition. DESIGN Secondary analyses were performed in an observational setting of 222 pregnant women with a pregestational BMI (in kg/m(2)) ≥30 participating in a randomized controlled trial. Diet was assessed at gestational weeks 11-14 and 36-37 by using a semiquantitative food-frequency questionnaire. Body composition in the offspring was assessed at birth by dual-energy X-ray absorptiometry. Relative fat mass (%) was the primary outcome. Absolute measures (total fat, abdominal fat, and lean body mass) were secondary outcomes. RESULTS Mean ± SD weight and absolute and relative fat mass in the offspring at birth were 3769 ± 542 g, 436 ± 214 g, and 11% ± 4%, respectively. Maternal intake of digestible carbohydrates was associated with the offsprings relative fat mass in late (P-trend = 0.006) but not early (P-trend = 0.15) pregnancy. A comparison of mothers in the highest (median: 238 g/d) compared with the lowest (median: 188 g/d) quartile of digestible carbohydrate intake showed a mean adjusted higher value in the offsprings relative fat mass of 2.1% (95% CI: 0.6%, 3.7%), which corresponded in absolute terms to a 103-g (95% CI: 27, 179-g) higher fat mass. Abdominal fat mass was also higher. In a strata of women with well-controlled glucose (2-h glucose values ≤6.6 mmol/L), no association between carbohydrate intake and offspring fat mass was observed, but the associations became significant and increased in strength with higher intolerance (strata with 2-h glucose values between 6.7-7.7 and ≥7.8 mmol/L). CONCLUSION In obese women, even those without gestational diabetes but with impaired glucose tolerance, a lower carbohydrate intake at moderate levels in late gestation is associated with a lower fat mass in their offspring at birth. The TOP study was registered at clinicaltrials.gov as NCT01345149.

Intake of Sweets, Snacks and Soft Drinks Predicts Weight Gain in Obese Pregnant Women: Detailed Analysis of the Results of a Randomised Controlled Trial

Background Lifestyle interventions targeting obese pregnant women often result in modest reduction in gestational weight gain, pregnancy complications and related risk factors. Examining adherence to the intervention can, however, provide valuable information on the importance of the different factors targeted. Objective To evaluate improvements and relevance of different dietary factors targeted with respect to gestational weight gain in a 3-arm Randomised Controlled Trial (n=342) among obese pregnant women with BMI≥30 kg/m2. Methods Randomisation 1:1:1 to either hypocaloric Mediterranean type of diet and physical activity intervention (D+PA); physical activity intervention alone (PA); or control (C). Diet was assessed at baseline (weeks 11–14) and endpoint (weeks 36–37) using a validated food frequency questionnaire. Results During the intervention women in the D+PA group significantly lowered their intakes of added sugars and saturated fat and increased their protein intake by ~1% of total energy compared to controls. Of these dietary variables only intakes of added sugar appeared to be related to GWG, while no association was observed for saturated fat or protein. Further analyses revealed that foods that contributed to intake of added sugars, including sweets, snacks, cakes, and soft drinks were strongly associated with weight gain, with women consuming sweets ≥2/day having 5.4 kg (95% CI 2.1-8.7) greater weight gain than those with a low (<1wk) intake. The results for soft drinks were more conflicting, as women with high weight gain tended to favour artificially sweetened soft drinks. Conclusion In our sample of obese pregnant women, craving for sweets, snacks, and soft drinks strongly predicts GWG. Emphasis on reducing intakes of these foods may be more relevant for limiting gestational weight gain than encouraging strict compliance to more specific diets. Trial Registration ClinicalTrials.gov NCT01345149