***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: INTRODUCTION Walking may be a strategy for increasing moderate-intensity physical activity ( MPA )  during pregnancy . PURPOSE This study aim ed to promote MPA among overweight and obese pregnant women , via walking , and to evaluate the effect of the intervention on maternal and birth outcomes . METHODS Thirty-seven overweight or obese pregnant women were r and omly assigned to a walking intervention or control group . Anthropometric and objective PA ( StepWatch ™ Activity Monitor ) data were collected for four 1-wk periods : weeks 10 - 14 ( V1 ) , weeks 17 - 19 ( V2 ) , weeks 27 - 29 ( V3 ) , and weeks 34 - 36 ( V4 ) of gestation . Participants provided information about maternal and birth outcomes . A cadence of ≥ 80 steps per minute was defined as MPA , and " meaningful walking " was defined as moderate walking in ≥ 8-min bouts . ANOVA was used to determine the differences in walking amount and meaningful walks , the Kolmogorov-Smirnov test was used for walking intensity distribution analysis , and Fisher 's exact test was used for maternal and infant outcomes analyses . Pearson correlation was used to examine the association between prepregnancy body mass index and gestational weight gain ( GWG ) . RESULTS There was significantly more MPA among women in the intervention group compared with those in the control group at V2 ( overweight , P < 0.0001 ; obese , P < 0.025 ) , V3 ( overweight , P < 0.0001 ) , and V4 ( overweight , P < 0.0001 ; obese , P < 0.025 ) . Women in the intervention group significantly increased their meaningful walks at V2 ( P = 0.054 ) , V3 ( P = 0.01 ) , and V4 ( P = 0.014 ) . There were trends for intervention group women to have more favorable maternal and birth outcomes compared with the control group . Rates of GWG at measurement points during pregnancy were significantly associated with preceding rates of GWG . CONCLUSION The pilot , unsupervised walking intervention increased the MPA of overweight and obese women during pregnancy Objective To determine the effect of antenatal dietary and lifestyle interventions on health outcomes in overweight and obese pregnant women . Design Multicentre r and omised trial . We utilised a central telephone r and omisation server , with computer generated schedule , balanced variable blocks , and stratification for parity , body mass index ( BMI ) category , and hospital . Setting Three public maternity hospitals across South Australia . Participants 2212 women with a singleton pregnancy , between 10 + 0 and 20 + 0 weeks ’ gestation , and BMI ≥25 . Interventions 1108 women were r and omised to a comprehensive dietary and lifestyle intervention delivered by research staff ; 1104 were r and omised to st and ard care and received pregnancy care according to local guidelines , which did not include such information . Main outcome measures Incidence of infants born large for gestational age ( birth weight ≥90th centile for gestation and sex ) . Prespecified secondary outcomes included birth weight > 4000 g , hypertension , pre-eclampsia , and gestational diabetes . Analyses used intention to treat principles . Results 2152 women and 2142 liveborn infants were included in the analyses . The risk of the infant being large for gestational age was not significantly different in the two groups ( lifestyle advice 203/1075 ( 19 % ) v st and ard care 224/1067 ( 21 % ) ; adjusted relative risk 0.90 , 95 % confidence interval 0.77 to 1.07 ; P=0.24 ) . Infants born to women after lifestyle advice were significantly less likely to have birth weight above 4000 g ( lifestyle advice 164/1075 ( 15 % ) v st and ard care 201/1067 ( 19 % ) ; 0.82 , 0.68 to 0.99 ; number needed to treat ( NNT ) 28 , 15 to 263 ; P=0.04 ) . There were no differences in maternal pregnancy and birth outcomes between the two treatment groups . Conclusions For women who were overweight or obese , the antenatal lifestyle advice used in this study did not reduce the risk delivering a baby weighing above the 90th centile for gestational age and sex or improve maternal pregnancy and birth outcomes . Trial registration Australian and New Zeal and Clinical Trials Registry ( ACTRN12607000161426 ) OBJECTIVE Optimizing gestational weight gain ( GWG ) in early pregnancy is of clinical and public health importance , especially in higher risk pregnancies . DESIGN AND METHODS In a robustly design ed , r and omized controlled trial , 228 pregnant women at risk of developing gestational diabetes mellitus ( GDM ) were allocated to either control ( written health information only ) or intervention ( four-session lifestyle program ) . All women received st and ard maternal care . Measures were completed at 12 - 15 and 26 - 28 weeks gestation . Measures included anthropometrics ( weight and height ) , physical activity ( pedometer and International Physical Activity Question naire ) , question naires ( risk perception ) , and GDM screening . RESULTS The mean ( SD ) age [ 31.7 ( 4.5 ) and 32.4 ( 4.7 ) years ] and body mass index [ BMI ; 30.3 ( 5.9 ) and 30.4 ( 5.6 ) kg/m(2 ) ] were similar between control and intervention groups , respectively . By 28 weeks , GWG was significantly different between control and intervention groups [ 6.9 ( 3.3 ) vs. 6.0 ( 2.8 ) kg , P < 0.05 ] . When stratified according to baseline BMI , overweight women in the control group gained significantly more weight compared to overweight women in the intervention group [ 7.8 ( 3.4 ) vs. 6.0 ( 2.2 ) kg , P < 0.05 ] , yet in obese women , GWG was similar in both groups . Physical activity levels declined by 28 weeks gestation overall ( P < 0.01 ) ; however , the intervention group retained a 20 % higher step count compared to controls [ 5,203 ( 3,368 ) vs. 4,140 ( 2,420 ) steps/day , P < 0.05 ] . Overall , GDM prevalence was 22.8 % [ Corrected ] , with a trend toward less cases in the intervention group ( P = 0.1 ) . CONCLUSIONS Results indicate that a low-intensity lifestyle intervention , integrated with antenatal care , optimizes healthy GWG and attenuates physical activity decline in early pregnancy . Efficacy in limiting weight gain was greatest in overweight women and in high-risk ethnically diverse women BACKGROUND Behavioural interventions might improve clinical outcomes in pregnant women who are obese . We aim ed to investigate whether a complex intervention addressing diet and physical activity could reduce the incidence of gestational diabetes and large-for-gestational-age infants . METHODS The UK Pregnancies Better Eating and Activity Trial ( UPBEAT ) is a r and omised controlled trial done at antenatal clinics in eight hospitals in multi-ethnic , inner-city locations in the UK . We recruited pregnant women ( 15 - 18 weeks plus 6 days of gestation ) older than 16 years who were obese ( BMI ≥30 kg/m(2 ) ) . We r and omly assigned participants to either a behavioural intervention or st and ard antenatal care with an internet-based , computer-generated , r and omisation procedure , minimising by age , ethnic origin , centre , BMI , and parity . The intervention was delivered once a week through eight health trainer-led sessions . Primary outcomes were gestational diabetes ( diagnosed with an oral glucose tolerance test and by criteria from the International Association of Diabetes in Pregnancy Study Groups ) and large-for-gestational-age infants ( ≥90th customised birthweight centile ) . Analysis was by intention to treat . This trial is registered with Current Controlled Trials , ISCRTN89971375 . Recruitment and pregnancy outcomes are complete but childhood follow-up is ongoing . FINDINGS Between March 31 , 2009 , and June 2 , 2014 , we assessed 8820 women for eligibility and recruited 1555 , with a mean BMI of 36·3 kg/m(2 ) ( SD 4·8 ) . 772 were r and omly assigned to st and ard antenatal care and 783 were allocated the behavioural intervention , of which 651 and 629 women , respectively , completed an oral glucose tolerance test . Gestational diabetes was reported in 172 ( 26 % ) women in the st and ard care group compared with 160 ( 25 % ) in the intervention group ( risk ratio 0·96 , 95 % CI 0·79 - 1·16 ; p=0·68 ) . 61 ( 8 % ) of 751 babies in the st and ard care group were large for gestational age compared with 71 ( 9 % ) of 761 in the intervention group ( 1·15 , 0·83 - 1·59 ; p=0·40 ) . Thus , the primary outcomes did not differ between groups , despite improvements in some maternal secondary outcomes in the intervention group , including reduced dietary glycaemic load , gestational weight gain , and maternal sum-of-skinfold thicknesses , and increased physical activity . Adverse events included neonatal death ( two in the st and ard care group and three in the intervention group ) and fetal death in utero ( ten in the st and ard care group and six in the intervention group ) . No maternal deaths were reported . Incidence of miscarriage ( 2 % in the st and ard care group vs 2 % in the intervention group ) , major obstetric haemorrhage ( 1 % vs 3 % ) , and small-for-gestational-age infants ( ≤5th customised birthweight centile ; 6 % vs 5 % ) did not differ between groups . INTERPRETATION A behavioural intervention addressing diet and physical activity in women with obesity during pregnancy is not adequate to prevent gestational diabetes , or to reduce the incidence of large-for-gestational-age infants . FUNDING National Institute for Health Research , Guys and St Thomas ' Charity , Chief Scientist Office Scotl and , Tommy 's Charity BACKGROUND The optimal diet for pregnancy that is complicated by excessive weight is unknown . OBJECTIVE We aim ed to examine the effects of a low-glycemic load ( low-GL ) diet in overweight and obese pregnant women . DESIGN We r and omly assigned 46 overweight or obese pregnant women to receive a low-GL or a low-fat diet .  Participants received carbohydrate-rich foods , fats , and snack foods through home delivery or study visits . The primary outcome was birth weight z score . Other endpoints included infant anthropometric measurements , gestational duration , maternal weight gain , and maternal metabolic parameters . RESULTS There were no significant differences in birth weight z score or other measures of infant adiposity between groups . However , in the low-GL compared with the low-fat group , gestational duration was longer ( mean ± SD : 39.3 ± 1.1 compared with 37.9 ± 3.1 wk ; P = 0.05 ) and fewer deliveries occurred at ≤ 38.0 wk ( 13 % compared with 48 % , P = 0.02 ; with exclusion of planned cesarean deliveries : 5 % compared with 53 % ; P = 0.002 ) . Adjusted head circumference was greater in the low-GL group ( 35.0 ± 0.8 compared with 34.2 ± 1.3 cm , P = 0.01 ) . Women in the low-GL group had smaller increases in triglycerides [ median ( interquartile range ) : 49 ( 19 , 70 ) compared with 93 ( 34 , 129 ) mg/dL ; P = 0.03 ] and total cholesterol [ 13 ( 0 , 36 ) compared with 33 ( 22 , 56 ) mg/dL , P = 0.04 ] and a greater decrease in C-reactive protein [ -2.5 ( -5.5 , -0.7 ) compared with -0.4 ( -1.4 , 1.5 ) mg/dL , P = 0.007 ] . CONCLUSIONS A low-GL diet result ed in longer pregnancy duration , greater infant head circumference , and improved maternal cardiovascular risk factors . Large-scale studies are warranted to evaluate whether dietary intervention during pregnancy aim ed at lowering GL may be useful in the prevention of prematurity and other adverse maternal and infant outcomes . This trial is registered at clinical trials.gov as NCT00364403 Background The effectiveness of exercise training for preventing excessive gestational weight gain ( GWG ) and gestational diabetes mellitus ( GDM ) is still uncertain . As maternal obesity is associated with both GWG and GDM , there is a special need to assess whether prenatal exercise training programs provided to obese women reduce the risk of adverse pregnancy outcomes . Our primary aim was to assess whether regular supervised exercise training in pregnancy could reduce 
    Output:
    
Physical activity did not show a significant pooled effect .
Healthy eating and /or physical activity are effective in gestational weight gain control .
Healthy eating with calorie and macronutrient goals are especially effective in limiting excessive gestational weight gain among pregnant overweight and obese women