Lifestyle intervention to limit gestational weight gain: the Norwegian Fit for Delivery randomised controlled trial

Effectiveness of exercise interventions in the prevention of excessive gestational weight gain and postpartum weight retention: a systematic review and meta-analysis

Objective

Gestational weight gain (GWG) has been identified as a critical modifier of maternal and fetal health. This systematic review and meta-analysis aimed to examine the relationship between prenatal exercise, GWG and postpartum weight retention (PPWR).

Design

Systematic review with random effects meta-analysis and meta-regression. Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs in English, Spanish or French were eligible (except case studies and reviews) if they contained information on the population (pregnant women without contraindication to exercise), intervention (frequency, intensity, duration, volume or type of exercise, alone [“exercise-only”] or in combination with other intervention components [eg, dietary; “exercise + co-intervention”]), comparator (no exercise or different frequency, intensity, duration, volume or type of exercise) and outcomes (GWG, excessive GWG (EGWG), inadequate GWG (IGWG) or PPWR).

Results

Eighty-four unique studies (n=21 530) were included. ‘Low’ to ‘moderate’ quality evidence from randomised controlled trials (RCTs) showed that exercise-only interventions decreased total GWG (n=5819; −0.9 kg, 95% CI −1.23 to –0.57 kg, I2=52%) and PPWR (n=420; −0.92 kg, 95% CI −1.84 to 0.00 kg, I2=0%) and reduced the odds of EGWG (n=3519; OR 0.68, 95% CI 0.57 to 0.80, I2=12%) compared with no exercise. ‘High’ quality evidence indicated higher odds of IGWG with prenatal exercise-only (n=1628; OR 1.32, 95% CI 1.04 to 1.67, I2=0%) compared with no exercise.

Conclusions

Prenatal exercise reduced the odds of EGWG and PPWR but increased the risk of IGWG. However, the latter result should be interpreted with caution because it was based on a limited number of studies (five RCTs).

Glucose responses to acute and chronic exercise during pregnancy: a systematic review and meta-analysis

Objective

To perform a systematic review and meta-analysis to explore the relationship between prenatal exercise and glycaemic control.

Design

Systematic review with random-effects meta-analysis and meta-regression.

Data sources

Online databases were searched up to 6 January 2017.

Study eligibility criteria

Studies of all designs were included (except case studies and reviews) if they were published in English, Spanish or French, and contained information on the population (pregnant women without contraindication to exercise), intervention (subjective or objective measures of frequency, intensity, duration, volume or type of acute or chronic exercise, alone (‘exercise-only’) or in combination with other intervention components (eg, dietary; ‘exercise+cointervention’) at any stage of pregnancy), comparator (no exercise or different frequency, intensity, duration, volume and type of exercise) and outcome (glycaemic control).

Results

A total of 58 studies (n=8699) were included. There was ‘very low’ quality evidence showing that an acute bout of exercise was associated with a decrease in maternal blood glucose from before to during exercise (6 studies, n=123; mean difference (MD) −0.94 mmol/L, 95% CI −1.18 to −0.70, I2=41%) and following exercise (n=333; MD −0.57 mmol/L, 95% CI −0.72 to −0.41, I2=72%). Subgroup analysis showed that there were larger decreases in blood glucose following acute exercise in women with diabetes (n=26; MD −1.42, 95% CI −1.69 to −1.16, I2=8%) compared with those without diabetes (n=285; MD −0.46, 95% CI −0.60 to −0.32, I2=62%). Finally, chronic exercise-only interventions reduced fasting blood glucose compared with no exercise postintervention in women with diabetes (2 studies, n=70; MD −2.76, 95% CI −3.18 to −2.34, I2=52%; ‘low’ quality of evidence), but not in those without diabetes (9 studies, n=2174; MD −0.05, 95% CI −0.16 to 0.05, I2=79%).

Conclusion

Acute and chronic prenatal exercise reduced maternal circulating blood glucose concentrations, with a larger effect in women with diabetes.

Gestational Weight Gain Intervention Impacts Determinants of Healthy Eating and Exercise in Overweight/Obese Pregnant Women

High gestational weight gain (GWG) in overweight/obese pregnant women increases maternal-fetal complications. We conducted a 6-week GWG intervention based on an energy balance model that includes theories of planned behavior (TPB) and self-regulation constructs to promote exercise and healthy eating motivation and behaviors. The purposes of this proof-of-concept feasibility study were to examine: (1) the energy balance model constructs over the intervention, and (2) pre-post intervention, weekly, and dose-response changes in study constructs. Methods. Overweight/obese pregnant women (N=17) were randomized to 1 of 6 conditions, increasing in intensity, and included varied combinations of components (exercise sessions, healthy eating demonstrations, etc.). Exercise and healthy eating TPB (attitude, subjective norm, perceived behavioral control, intention), and self-regulation (prospective, retrospective) constructs were collected weekly. Exercise behavior, energy intake, and GWG were collected daily. Results. We observed: (a) significant increases in exercise TPB constructs, healthy eating attitude (limit unhealthy foods), exercise/healthy eating retrospective self-regulation; (b) significant decrease in healthy eating subjective norm (limit unhealthy foods); (c) trending increases for healthy eating perceived behavioral control (limit unhealthy foods), healthy eating prospective self-regulation, and energy intake; (d) significantly higher active time, steps, and energy expenditure at W3 relative to other weeks; (e) no significant increase in GWG; and, (f) a dose response effect such that women in more intensive dosages had greater gains in exercise and healthy eating perceived behavioral control (eat healthy/limit unhealthy foods). Conclusion. Brief exposure to a theoretically-driven, GWG intervention resulted in changes to exercise and healthy eating TPB and self-regulation motivational determinants, no significant increase in GWG, and suggests intervention intensity can strengthen perceived ability to engage in exercise/healthy eating behaviors; offering initial proof-of-concept for the intervention to regulate GWG in overweight/obese pregnant women. Future research will test this intervention over the course of pregnancy to understand long-term impact on maternal-fetal health outcomes.

Pre-pregnancy and early pregnancy dietary behavior in relation to maternal and newborn health in the Norwegian Fit for Delivery study - a post hoc observational analysis

Background

Randomized controlled trials targeting maternal dietary and physical activity behaviors during pregnancy have generally failed to accomplish reductions in the prevalence of adverse maternal and neonatal outcomes. Interventions carried out during pregnancy could thus be missing the mark in maximizing intervention health benefit.

Objective

To investigate whether pre-pregnancy and early pregnancy dietary behavior as reported at inclusion into the Norwegian Fit for Delivery (NFFD) trial was associated with maternal and neonatal outcomes irrespective of subsequent randomization assignment.

Design

The study is a post-hoc observational analysis of data from a randomized controlled lifestyle intervention. We constructed two diet scores from participant responses to a 43-item questionnaire that addressed dietary behavior in retrospect (pre-pregnancy diet score) and dietary behavior at inclusion (early pregnancy diet score), respectively. The diet scores ranged from 0 to 10, with higher score reflecting healthier dietary behavior. Associations between diet scores and maternal and neonatal health outcomes were estimated in multivariate logistic regression models.

Results

A total of 591 women were eligible for analysis. A one-point increase in pre-pregnancy diet score was associated with lower odds of excessive gestational weight gain (GWG) (odds ratio [OR]_adj: 0.92; 95% confidence interval [CI]: 0.84-1.00, p = 0.050), preterm delivery (OR_adj: 0.81; 95% CI: 0.68-0.97, p = 0.019), and birthweight ≥ 4,000 g (OR_adj: 0.88; 95% CI: 0.78-0.99, p = 0.038). A one-point increase in early pregnancy diet score was associated with lower odds of excessive GWG (OR_adj: 0.88; 95% CI: 0.79-0.97, p = 0.009), preterm delivery (OR_adj: 0.82; 95% CI: 0.67-0.99, p = 0.038), and preeclampsia (OR_adj: 0.78; 95% CI: 0.62-0.99, p = 0.038).

Discussion

Higher diet score either pre-pregnancy or in early pregnancy was protectively associated with excessive GWG and preterm delivery, whereas the protective association with high birthweight was confined to pre-pregnancy diet and with preeclampsia to early pregnancy diet.

Conclusions

Both pre-pregnancy and early pregnancy dietary behavior was associated with important maternal and neonatal health outcomes in the NFFD dataset.

Ethnic Disparities in Gestational Diabetes

PURPOSE OF REVIEW

Ethnicity has long been described as a major risk factor for the development of gestational diabetes mellitus (GDM), and it is widely recognised that women from ethnicities other than Europids are at higher risk of developing GDM. There are also described differences between ethnicities in key GDM pregnancy outcomes. This review describes some of the factors that relate to the ethnic disparities in GDM.

RECENT FINDINGS

The global prevalence of GDM has been steadily increasing and estimated to be 16.2% from the International Diabetes Federation extrapolation. Reported prevalence rates may understate the true prevalence, due to factors of access and attitudes to GDM diagnosis and screening in low resource settings for foreign-born women and indigenous populations. Other factors may relate to genes associated with specific ethnicities, obesity, body composition and gestational weight gain. Various factors such as access to screening, body composition, genetics and gestational weight gain may result in ethnic disparities in the prevalence and outcomes of GDM.

Attenuating Pregnancy Weight Gain-What Works and Why: A Systematic Review and Meta-Analysis

Excessive maternal gestational weight gain (GWG) contributes to generational obesity. Our aim was to explore efficacy and intervention characteristics (trimester, duration, frequency, intensity, and delivery method) of interventions to prevent excessive GWG. CINAHL, Cochrane, EMBASE, LILACS, MEDLINE, PsycINFO, and Scopus were searched up to May 2018 (no date or language restrictions). Keywords and MeSH terms for diet, GWG, intervention, lifestyle, maternal, physical activity, and pregnancy were used to locate randomized-controlled trials (RCTs). The Cochrane Collaboration tool for assessing risk of bias was applied. Eighty-nine RCTs were included. Meta-analysis (60 trials) estimated that women in diet only (WMD: -3.27; 95% CI: -4.96, -1.58, p < 0.01), physical activity (PA) (WMD: -1.02; 95% CI: -1.56, -0.49, p < 0.01), and lifestyle interventions (combining diet and PA) (WMD: -0.84; 95% CI: -1.29, -0.39, p < 0.01) gained significantly less weight than controls. The three eHealth interventions favored neither intervention nor control (WMD: -1.06; 95% CI: -4.13, 2.00, p = 0.50). Meta-regression demonstrated no optimal duration, frequency, intensity, setting, or diet type. Traditional face to face delivery of weight management interventions during pregnancy can be successful. Delivery via eHealth has potential to extend its reach to younger women but needs further evaluation of its success.

Interventions designed to reduce excessive gestational weight gain can reduce the incidence of gestational diabetes mellitus: A systematic review and meta-analysis of randomised controlled trials

AIMS

To (i) evaluate the global impact of interventions designed to prevent excessive gestational weight gain (eGWG) on the incidence of gestational diabetes (GDM), and (ii) examine whether the effects differ by pre-conception body mass index (BMI) or ethnicity.

METHODS

A systematic search of randomised controlled trials (RCTs) with a primary or secondary aim to reduce eGWG was conducted in seven international and three Chinese databases without date limits. Meta-analysis data are reported as relative risk (RR) for GDM incidence for interventions including: diet, physical activity (PA), and lifestyle (diet and PA).

RESULTS

Forty-five studies were included, 37 in the meta-analyses. Diet and PA interventions reduced GDM risk by 44% (RR: 0.56, 95% CI: 0.36-0.87) and 38% (RR: 0.62, 95% CI: 0.50-0.78), respectively. Lifestyle interventions and BMI didn't significantly alter GDM risk. PA interventions from Southern-Europe reduced GDM risk by 37% (RR: 0.63, 95% CI: 0.50-0.80). Whereas, diet and lifestyle interventions conducted in Asia reduced GDM risk by 62% (RR: 0.38, 95% CI: 0.24-0.59) and 32% (RR: 0.68, 95% CI: 0.54-0.86), respectively.

CONCLUSION

Diet and PA interventions designed to reduce GWG are more effective than standard care in reducing the incidence of GDM, although the effect varies by region and BMI. The 'one size fits all' approach is not supported.

Gestational Weight Gain and Pregnancy Complications in a High-Risk, Racially and Ethnically Diverse Population

BACKGROUND

Evidence used to guide the current Institute of Medicine (IOM) gestational weight gain (GWG) recommendations is largely derived from studies of European descent, and as such the guidelines are the same for all races and ethnicities. The guidelines are also the same for prepregnancy obesity classes I through III.

OBJECTIVE

Considering these literature gaps, we aim to (1) determine the association between the IOM GWG guidelines and three common pregnancy complications: preeclampsia, gestational diabetes mellitus, and cesarean delivery in a racially and ethnically diverse population; and (2) assess whether the association between GWG and pregnancy complications differs by race/ethnicity or prepregnancy body mass index (BMI) categories, particularly obesity classes I through III.

METHODS

To address these aims, we analyzed data from the Boston Birth Cohort. We calculated GWG using data from electronic medical records or, when missing, from a postdelivery questionnaire. We examined GWG continuously and categorically using the IOM formula.

RESULTS

Of the 5,568 women included, 54.5% met the IOM criterion for excessive GWG. Compared to women who had adequate GWG, women who gained excessive weight had 1.65 (95% confidence interval [CI] 1.27-2.14) times greater odds of preeclampsia; 1.68 (95% CI 1.15-2.46) times greater odds of gestational diabetes; and no significant change in odds of cesarean delivery (odds ratio [OR] = 1.14, 95% CI 0.99-1.31). Associations did not differ by race, ethnicity, or prepregnancy BMI categories including comparisons of obesity class I versus II or III (all p-values for interaction >0.05).

CONCLUSIONS

In this racially and ethnically diverse population, excessive GWG was associated with higher odds of preeclampsia, gestational diabetes, and nonsignificantly, with cesarean delivery. Associations did not differ appreciably by race, ethnicity, or prepregnancy BMI categories. Our results support the relevance of the IOM GWG recommendations in racially and ethnically diverse populations, and in women in the higher prepregnancy obesity classes.

Is birth weight the major confounding factor in the study of gestational weight gain?: an observational cohort study

BACKGROUND

Much interest has been focussed on both maternal obesity and gestational weight gain (GWG), particularly on their role in influencing birth weight (BW). Several large reviews have reported that excessive GWG is associated with an increase in BW. However recent large, well-designed, randomized controlled trials studying interventions aimed at reducing GWG have all consistently failed to show a reduction in BW despite achieving a reduction in GWG. The aim of this longitudinal prospective study was to examine the relationship between GWG and birth weight in women where GWG and Body Mass Index (BMI) were measured accurately in a strictly standardized way.

METHODS

Women were enrolled at their convenience before 18 weeks gestation. Height and weight were measured accurately at the first antenatal visit and BMI calculated. Maternal weight was measured again after 37 weeks gestation. The weight of the baby was measured at birth. Relationships were tested using linear regression analysis, chi-squared tests and t-tests as appropriate.

RESULTS

Of the 522 women studied, the mean BMI was 25.3 kg/m2 and 15.7% were obese. The mean BW at term was 3576 g (2160-5120) and 2.7% (n = 14) weighed ≥4500 g. The mean GWG overall was 12.3 kg (4.6 to 28.4) and GWG decreased as BMI increased. The mean GWG was less in obese women, at 8.7 kg (- 4.6 to 23.4), compared to non-obese,13.0 kg (0.6-28.4) (p < 0.001). Mean BW in obese women was 3630 g vs 3565 g in non-obese (p = 0.27). The total GWG correlated positively with BW (p < 0.001). When BW was subtracted from total GWG, GWG no longer correlated with BW (p = 0.12).

CONCLUSIONS

The positive correlation between GWG in pregnancy and BW can be accounted for by the contribution of fetal weight to GWG antenatally without a contribution from increased maternal adiposity. There was a wide range of BW irrespective of the degree of GWG and obese women had a lower GWG than non-obese women. These findings help explain why Randomized Controlled Trials (RCTs) designed to reduce GWG have failed to decrease BW and suggest there is no causative link between excessive GWG and increased BW.

Maternal betaine supplementation affects fetal growth and lipid metabolism of high-fat fed mice in a temporal-specific manner

BACKGROUND/OBJECTIVES

Maternal obesity increases the risk of gestational diabetes mellitus (GDM), which results in fetal overgrowth and long-lasting metabolic dysfunctioning in the offspring. Previous studies show that maternal choline supplementation normalizes fetal growth and adiposity of progeny from obese mice. This study examines whether supplementation of betaine, a choline derivative, has positive effects on fetal metabolic outcomes in mouse progeny exposed to maternal obesity and GDM.

METHODS

C57BL/6J mice were fed either a high-fat (HF) diet or a control (normal-fat, NF) diet and received either 1% betaine (BS) or control untreated (BC) drinking water 4-6 weeks before timed-mating and throughout gestation. Maternal, placental, and fetal samples were collected for metabolite and gene-expression assays.

RESULTS

At E12.5, BS prevented fetal and placental overgrowth and downregulated glucose and fatty acid transporters (Glut1 and Fatp1) and the growth-promoting insulin-like growth factor 2 (Igf2) and its receptor Igf1r in the placenta of HF, glucose-intolerant dams (P < 0.05). However, these effects disappeared at E17.5. At E17.5, BS reduced fetal adiposity and prevented liver triglyceride overaccumulation in HF versus NF fetuses (P < 0.05). BS fetal livers had enhanced mRNA expression of microsomal triglyceride transfer protein (Mttp) (P < 0.01), which promotes VLDL synthesis and secretion. Although we previously reported that maternal choline supplementation downregulated mRNA expression of genes involved in de novo lipogenesis in fetal livers, such alterations were not observed with BS, suggesting differential effects of betaine and choline on fetal gene expression.

CONCLUSION

We propose a temporal-specific mechanism by which maternal BS influences fetal growth and lipid metabolic outcomes of HF mice during prenatal development.

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.

Preeclampsia and gestational weight gain in the Norwegian Fit for Delivery trial

Objective

Excessive gestational weight gain is linked to risk of preeclampsia, but it is not clear whether the association is causal. The purpose of this paper was to examine gestational weight gain in the Norwegian Fit for Delivery study among women who developed preeclampsia compared to those who did not, and to further explore associations between weight gain and preeclampsia by including data on body composition (bioimpedance) assessed in the last trimester of pregnancy.

Results

A total of 550 women were eligible for the study. Women who developed preeclampsia gained more weight than women who did not (difference 3.7 kg, p = 0.004), with a 3.5 kg difference in total body water observed in week 36 (p = 0.040). Adjusted for age, education, pre-pregnancy body mass index (BMI), randomization, and fat mass, a one kg increase in GWG was associated with 1.3 times higher odds of preeclampsia (OR: 1.31, 95% CI 1.15–1.49, p < 0.001). An independent inverse association between fat mass in week 36 and odds of preeclampsia was observed (OR: 0.79, 95% CI 0.68–0.92, p = 0.002). Given the observed difference in total body water, these findings point to excess fluid as the component driving the association between gestational weight gain and preeclampsia in the present study.

Trial registration The NFFD trial has the Clinical Trials registration: clinicaltrial.gov NCT0100168

How does a lifestyle intervention during pregnancy influence perceived barriers to leisure-time physical activity? The Norwegian fit for delivery study, a randomized controlled trial

BACKGROUND

To develop effective health promotional and preventive prenatal programs, it is important to understand perceived barriers to leisure-time physical activity during pregnancy, including exercise and sport participation. The aims of the present study was 1) to assess the effect of prenatal lifestyle intervention on the perceived barrier to leisure-time physical activity during pregnancy and the first year after delivery and 2) identify the most important perceived barriers to leisure-time physical activity at multiple time points during and after pregnancy.

METHODS

This secondary analysis was part of the Norwegian Fit for Delivery study, a combined lifestyle intervention evaluated in a blinded, randomized controlled trial. Healthy, nulliparous women with singleton pregnancy of ≤20 gestational weeks, age ≥ 18 years and body mass index ≥19 kg/m² were recruited via healthcare clinics in southern Norway, including urban and rural settings. Participants were randomized to either twice-weekly supervised exercise sessions and nutritional counselling (n = 303) or standard prenatal care (n = 303). The principal analysis was based on the participants who completed the standardized questionnaire assessing their perceived barriers to leisure-time physical activity at inclusion (gestational week 16, n = 589) and following intervention (gestational week 36, n = 509), as well as six months (n = 470) and 12 months (n = 424) postpartum.

RESULTS

Following intervention (gestation week 35.4 ± 1.0), a significant between-group difference in perceived barriers to leisure-time physical activity was found with respect to time constraints: "... I do not have the time" (intervention: 22 vs. control: 38, p = 0.030), mother-child safety concerns: "... afraid to harm the baby" (intervention: 8 vs. control: 25, p = 0.002) and self-efficacy: "... I do not believe/think that I can do it" (intervention: 3 vs. control: 10, p = 0.050). No positive effect was seen at postpartum follow-up. Intrapersonal factors (lack of time, energy and interest) were the most frequently perceived barriers, and consistent over time among all participants.

CONCLUSION

The intervention had effect on intrapersonal perceived barriers in pregnancy, but not in the postpartum period. Perceived barriers to leisure-time physical activity were similar from early pregnancy to 12 months postpartum.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01001689 , registered July 2, 2009.

Effect of a prenatal lifestyle intervention on physical activity level in late pregnancy and the first year postpartum

BACKGROUND

Despite documented health benefits for mother and baby, physical activity (PA)-level tends to decline in pregnancy. Overweight/obese and physically inactive women are two selected groups at increased risk of pregnancy complications. Thus, efficient strategies to maintain or increase PA-level in pregnancy and the postpartum period, especially among these women, are warranted. This secondary analysis examined the effect of a prenatal lifestyle-intervention on PA-level in late pregnancy and the first year postpartum, with subanalysis on initially physically active versus inactive and normal-weight versus overweight/obese women.

METHOD

The Norwegian Fit for Delivery (NFFD) randomized controlled trial included healthy primiparous women with singleton pregnancies and body mass index (BMI) ≥19 kg/m2 assigned to an intervention group, n = 303 (twice weekly group-exercises and dietary counseling) or a control group, n = 303 (standard prenatal care). The International Physical Activity Questionnaire short-form was used to assess PA-levels at inclusion (mean gestational week (GW) 16), GW 36, and six and 12 months postpartum.

RESULTS

At GW 36, a positive intervention-effect with a significant between-group difference in total PA-level compared to time of inclusion was found for the total group (530 MET-min/week, p = 0.001) and the subgroups of normal-weight (533 MET-min/week, p = 0.003) and initially active women (717 MET-min/week, p<0.001). Intervention-effect was dependent on exercise-adherence among overweight/obese and inactive women. Compared to time of inclusion, the intervention groups maintained total PA-level at GW 36, while total PA-level decreased in the control groups. The PA-levels increased postpartum, but with no significant differences between the randomization groups.

CONCLUSION

The NFFD prenatal combined lifestyle intervention had a significant effect on TPA-level in late pregnancy among women entering pregnancy normal-weight or physically active, thereby preventing the downward trend typically seen during pregnancy. Intervention-effect among overweight/obese and physically inactive women was, however, dependent on exercise-adherence. Long-term intervention-effect was not observed in the postpartum period.

Combined diet and exercise interventions for preventing gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) is associated with a wide range of adverse health consequences for women and their infants in the short and long term. With an increasing prevalence of GDM worldwide, there is an urgent need to assess strategies for GDM prevention, such as combined diet and exercise interventions. This is an update of a Cochrane review that was first published in 2015.

OBJECTIVES

To assess the effects of diet interventions in combination with exercise interventions for pregnant women for preventing GDM, and associated adverse health consequences for the mother and her infant/child.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (27 November 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and cluster-RCTs, comparing combined diet and exercise interventions with no intervention (i.e. standard care), that reported on GDM diagnosis as an outcome. Quasi-RCTs were excluded. Cross-over trials were not eligible for inclusion. We planned to include RCTs comparing two or more different diet/exercise interventions, however none were identified.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data, assessed the risk of bias of the included trials and assessed quality of evidence for selected maternal and infant/child outcomes using the GRADE approach. We checked data for accuracy.

MAIN RESULTS

In this update, we included 23 RCTs (involving 8918 women and 8709 infants) that compared combined diet and exercise interventions with no intervention (standard care). The studies varied in the diet and exercise programs evaluated and health outcomes reported. None reported receiving funding from a drug manufacturer or agency with interests in the results. Overall risk of bias was judged to be unclear due to the lack of methodological detail reported. Most studies were undertaken in high-income countries.For our primary review outcomes, there was a possible reduced risk of GDM in the diet and exercise intervention group compared with the standard care group (average risk ratio (RR) 0.85, 95% confidence interval (CI) 0.71 to 1.01; 6633 women; 19 RCTs; Tau² = 0.05; I² = 42%; P = 0.07; moderate-quality evidence). There was also a possible reduced risk of caesarean section (RR 0.95, 95% CI 0.88 to 1.02; 6089 women; 14 RCTs; moderate-quality evidence). No clear differences were seen between groups for pre-eclampsia (RR 0.98, 95% CI 0.79 to 1.22; 5366 participants; 8 RCTs; low-quality evidence), pregnancy-induced hypertension and/or hypertension (average RR 0.78, 95% CI 0.47 to 1.27; 3073 participants; 6 RCTs; Tau² = 0.19; I² = 62%; very low-quality evidence), perinatal mortality (RR 0.82, 95% CI 0.42 to 1.63; 3757 participants; 2 RCTs; low-quality evidence) or large-for-gestational age (RR 0.93, 95% CI 0.81 to 1.07; 5353 participants; 11 RCTs; low-quality evidence). No data were reported for infant mortality or morbidity composite.Subgroup analyses (based on trial design, maternal body mass index (BMI) and ethnicity) revealed no clear differential treatment effects. We were unable to assess the impact of maternal age, parity and specific features of the diet and exercise interventions. Findings from sensitivity analyses (based on RCT quality) generally supported those observed in the main analyses. We were not able to perform subgroup analyses based on maternal age, parity or nature of the exercise/dietary interventions due to the paucity of information/data on these characteristics and the inability to meaningfully group intervention characteristics.For most of the secondary review outcomes assessed using GRADE, there were no clear differences between groups, including for perineal trauma (RR 1.27, 95% CI 0.78 to 2.05; 2733 participants; 2 RCTs; moderate-quality evidence), neonatal hypoglycaemia (average RR 1.42, 95% CI 0.67 to 2.98; 3653 participants; 2 RCTs; Tau² = 0.23; I² = 77%; low quality evidence); and childhood adiposity (BMI z score) (MD 0.05, 95% CI -0.29 to 0.40; 794 participants; 2 RCTs; Tau² = 0.04; I² = 59%; low-quality evidence). However, there was evidence of less gestational weight gain in the diet and exercise intervention group compared with the control group (mean difference (MD) -0.89 kg, 95% CI -1.39 to -0.40; 5052 women; 16 RCTs; Tau² = 0.37; I² = 43%;moderate-quality evidence). No data were reported for maternal postnatal depression or type 2 diabetes; childhood/adulthood type 2 diabetes, or neurosensory disability.

AUTHORS' CONCLUSIONS

Moderate-quality evidence suggests reduced risks of GDM and caesarean section with combined diet and exercise interventions during pregnancy as well as reductions in gestational weight gain, compared with standard care. There were no clear differences in hypertensive disorders of pregnancy, perinatal mortality, large-for-gestational age, perineal trauma, neonatal hypoglycaemia, and childhood adiposity (moderate- tovery low-quality evidence).Using GRADE methodology, the evidence was assessed as moderate to very low quality. Downgrading decisions were predominantly due to design limitations (risk of bias), and imprecision (uncertain effect estimates, and at times, small sample sizes and low event rates), however two outcomes (pregnancy-induced hypertension/hypertension and neonatal hypoglycaemia), were also downgraded for unexplained inconsistency (statistical heterogeneity).Due to the variability of the diet and exercise components tested in the included studies, the evidence in this review has limited ability to inform practice. Future studies could describe the interventions used in more detail, if and how these influenced behaviour change and ideally be standardised between studies. Studies could also consider using existing core outcome sets to facilitate more standardised reporting.

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

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.

Interpregnancy weight changes and impact on pregnancy outcome in a cohort of women with a macrosomic first delivery: a prospective longitudinal study

OBJECTIVE

To determine the median interpregnancy maternal weight change between first and second pregnancies, and second and third pregnancies and to assess the impact of this weight change on pregnancy outcome in a cohort of women with a macrosomic first delivery.

STUDY DESIGN

Prospective longitudinal study conducted over three pregnancies from 2007 to 2015.

SETTING

Tertiary referral maternity hospital, Dublin, Ireland.

PARTICIPANTS

Women were recruited if their first baby weighed >4.0 kg.

METHODS

The pregnancy outcomes in the second and third pregnancies were analysed separately. Data were also analysed for both interpregnancy intervals comparing outcomes for those who gained any weight, or more weight than the median, with those who did not.

MAIN OUTCOME MEASURES

Recurrent fetal macrosomia ≥4.0 kg and gestational diabetes mellitus.

RESULTS

There were 280 women who delivered a third baby between 2011 and 2015. There were no differences in pregnancy outcomes for the second pregnancy in women who gained interpregnancy weight compared with those who did not and those who gained more interpregnancy weight than the median compared with those who did not. There was a statistically significant increase in birth weight ≥4.0 kg (54.0% vs 39.6% p=0.03) in those women who gained any weight between the second and third pregnancies. In those women who gained more interpregnancy weight than the median (1.70 kg) between a second and third pregnancy, there was a significant increase in the rate of gestational diabetes (6.5% vs 1.4%, p=0.03).

CONCLUSIONS

This longitudinal study demonstrates that within this cohort maternal interpregnancy weight change between a second and third pregnancy is associated with an increase in birth weight ≥4.0 kg. Additionally, a gain of more weight than the median (1.70 kg) is associated with a higher rate of gestational diabetes.

The effect of a prenatal lifestyle intervention on glucose metabolism: results of the Norwegian Fit for Delivery randomized controlled trial

Background

The effectiveness of prenatal lifestyle intervention to prevent gestational diabetes and improve maternal glucose metabolism remains to be established. The Norwegian Fit for Delivery (NFFD) randomized, controlled trial studied the effect of a combined lifestyle intervention provided to a general population, and found significantly lower gestational weight gain among intervention participants but no improvement in obstetrical outcomes or the proportion of large infants. The aim of the present study is to examine the effect of the NFFD intervention on glucose metabolism, including an assessment of the subgroups of normal-weight and overweight/obese participants.

Methods

Healthy, non-diabetic women expecting their first child, with pre-pregnancy body mass index (BMI) ≥19 kg/m², age ≥ 18 years and a singleton pregnancy of ≤20 gestational-weeks were enrolled from healthcare clinics in southern Norway. Gestational weight gain was the primary endpoint. Participants (n = 606) were individually randomized to intervention (two dietary consultations and access to twice-weekly exercise groups) or control group (routine prenatal care). The effect of intervention on glucose metabolism was a secondary endpoint, measuring glucose (fasting and 2-h following 75-g glucose load), insulin, homeostatic assessment of insulin resistance (HOMA-IR) and leptin levels at gestational-week 30.

Results

Blood samples from 557 (91.9%) women were analyzed. For the total group, intervention resulted in reduced insulin (adj. Mean diff −0.91 mU/l, p = 0.045) and leptin levels (adj. Mean diff -207 pmol/l, p = 0.021) compared to routine care, while glucose levels were unchanged. However, the effect of intervention on both fasting and 2-h glucose was modified by pre-pregnancy BMI (interaction p = 0.030 and p = 0.039, respectively). For overweight/obese women (n = 158), intervention was associated with increased risk of at least one glucose measurement exceeding International Association of Pregnancy and Diabetes Study Group thresholds (33.7% vs. 13.9%, adj. OR 3.89, p = 0.004).

Conclusions

The Norwegian Fit for Delivery intervention lowered neither glucose levels nor GDM incidence, despite reductions in insulin and leptin. Prenatal combined lifestyle interventions designed for a general population may be unsuited to reduce GDM risk, particularly among overweight/obese women, who may require earlier and more targeted interventions.

Trial registration

ClinicalTrials.gov ID NCT01001689, registered July 2, 2009, confirmed completed October 26, 2009 (retrospectively registered).

Changes in fruit and vegetable consumption habits from pre-pregnancy to early pregnancy among Norwegian women

BACKGROUND

A healthy diet is important for pregnancy outcome and the current and future health of woman and child. The aims of the study were to explore the changes from pre-pregnancy to early pregnancy in consumption of fruits and vegetables (FV), and to describe associations with maternal educational level, body mass index (BMI) and age.

METHODS

Healthy nulliparous women were included in the Norwegian Fit for Delivery (NFFD) trial from September 2009 to February 2013, recruited from eight antenatal clinics in southern Norway. At inclusion, in median gestational week 15 (range 9-20), 575 participants answered a food frequency questionnaire (FFQ) where they reported consumption of FV, both current intake and recollection of pre-pregnancy intake. Data were analysed using a linear mixed model.

RESULTS

The percentage of women consuming FV daily or more frequently in the following categories increased from pre-pregnancy to early pregnancy: vegetables on sandwiches (13 vs. 17%, p <0.01), other vegetables (11 vs. 14%, p = 0.01), fruits (apples, pears, oranges or bananas) (24 vs. 41%, p < 0.01), other fruits and berries (8 vs. 15%, p < 0.01) and fruits and vegetables as snacks (14 vs. 28%, p < 0.01). The percentage of women who reported at least daily consumption of vegetables with dinner (22% at both time points) was stable. A higher proportion of older women increased their consumption of vegetables and fruits as snacks from pre-pregnancy to early pregnancy compared to younger women (p=0.04).

CONCLUSIONS

We found an increase in the proportion of women consuming FV daily or more frequently from pre-pregnancy to early pregnancy.

TRIAL REGISTRATION

ClinicalTrials.gov database, NCT01001689 . https://clinicaltrials.gov/ct2/show/NCT01001689?term=NCT01001689&rank=1 .

Nonpharmacological interventions to prevent type 2 diabetes in women diagnosed with gestational diabetes mellitus: a systematic overview

This systematic overview summarizes the relevant evidence from multiple systematic reviews of the benefits of nonpharmacological interventions for preventing type 2 diabetes mellitus (T2MD) in women diagnosed with gestational diabetes mellitus (GDM). A comprehensive search using the Cochrane Library, CINAHL, EMBASE and MEDLINE via Ovid SP, and PubMed databases was completed on 18 November 2015. Any systematic reviews that evaluated randomized controlled trials (RCTs) with defined nonpharmacological interventions for preventing T2DM in women diagnosed with GDM were eligible for inclusion. The authors independently performed critical appraisals and quality assessments of the included reviews using the AMSTAR tool, and extracted data were converted to coherent values for tabular summarization. Six eligible reviews of diet and/or exercise, breastfeeding, and reminder interventions were identified; however, the methodologies of the reviews varied greatly, and the majority of the evidence suggested unclear bias. We found inconsistent reporting on the rates at which diet and exercise interventions reduced the risk of T2DM progression, but these interventions were found to be effective at reducing glycemic load. Combined diet, exercise, and breastfeeding interventions proved to be effective at returning women to their postpartum weight. Neither diet alone nor exercise alone proved to be effective at lowering the risk of T2DM. Overall, there was no robust evidence to support the hypothesis that nonpharmacological interventions are effective at lowering the risk of T2DM in women diagnosed with GDM, and there was no consistent evidence showing that these interventions improved the predictor outcomes of T2DM, such as glycemic load or anthropometric changes.

Obesity and pregnancy: mechanisms of short term and long term adverse consequences for mother and child

Obesity is the most common medical condition in women of reproductive age. Obesity during pregnancy has short term and long term adverse consequences for both mother and child. Obesity causes problems with infertility, and in early gestation it causes spontaneous pregnancy loss and congenital anomalies. Metabolically, obese women have increased insulin resistance in early pregnancy, which becomes manifest clinically in late gestation as glucose intolerance and fetal overgrowth. At term, the risk of cesarean delivery and wound complications is increased. Postpartum, obese women have an increased risk of venous thromboembolism, depression, and difficulty with breast feeding. Because 50-60% of overweight or obese women gain more than recommended by Institute of Medicine gestational weight guidelines, postpartum weight retention increases future cardiometabolic risks and prepregnancy obesity in subsequent pregnancies. Neonates of obese women have increased body fat at birth, which increases the risk of childhood obesity. Although there is no unifying mechanism responsible for the adverse perinatal outcomes associated with maternal obesity, on the basis of the available data, increased prepregnancy maternal insulin resistance and accompanying hyperinsulinemia, inflammation, and oxidative stress seem to contribute to early placental and fetal dysfunction. We will review the pathophysiology underlying these data and try to shed light on the specific underlying mechanisms.