Inadequate weight gain in obese women and the risk of small for gestational age (SGA): a systematic review and meta-analysis

Association between maternal gestation weight gain and preterm birth according to pre-pregnancy body mass index and HbA1c

BACKGROUND

To investigate the association between gestational weight gain (GWG) and preterm birth (PTB) according to pre-pregnancy body mass index (pp-BMI) and glycated haemoglobin (HbA1c) within the normal range.

METHODS

We conducted a population-based retrospective cohort study between July 2017 and January 2020 at Women's Hospital, Zhejiang University School of Medicine. Women were classified into three groups (inadequate GWG, appropriate GWG, and excessive GWG). In addition, women were divided into different subgroups according to pp-BMI and HbA1c. We estimated the odds ratios (OR) with 95% confidence intervals (CI) to assess the associations between GWG and the risk of PTB. Meanwhile, we adjusted for possible confounding factors, including maternal age, infant sex, family history of diabetes, education, pregnancy mode, delivery mode, parity, and gravidity.

RESULTS

The study involved 23,699 pregnant women, of which 1124 (4.70%) were PTB. Women who had inadequate GWG were found to have a significantly higher risk of PTB compared to women with appropriate GWG. In contrast, women with excessive GWG had a reduced risk of PTB. Similarly, GWG and PTB had similar risk associations in the HbA1c and pp-BMI subgroups. Among women with pp-BMI <18.5 kg/m2, women with inadequate GWG had a significantly increased risk of PTB compared with women in the control group (HbA1c 4.6-5.0%, appropriate GWG), and the risk increased with increasing HbA1c levels. Similar results were observed in women with normal pp-BMI.

CONCLUSIONS

There was a significant association between GWG and the risk of PTB, but the risk varied by pp-BMI and HbA1c levels. Reasonable weight gain during pregnancy is essential to prevent PTB. Furthermore, while HbA1c is within the normal range, the higher levels should be noticed.

Safety of low weight gain or weight loss in pregnancies with class 1, 2, and 3 obesity: a population-based cohort study

BACKGROUND

There are concerns that current gestational weight gain recommendations for women with obesity are too high and that guidelines should differ on the basis of severity of obesity. In this study we investigated the safety of gestational weight gain below current recommendations or weight loss in pregnancies with obesity, and evaluated whether separate guidelines are needed for different obesity classes.

METHODS

In this population-based cohort study, we used electronic medical records from the Stockholm-Gotland Perinatal Cohort study to identify pregnancies with obesity (early pregnancy BMI before 14 weeks' gestation ≥30 kg/m2) among singleton pregnancies that delivered between Jan 1, 2008, and Dec 31, 2015. The pregnancy records were linked with Swedish national health-care register data up to Dec 31, 2019. Gestational weight gain was calculated as the last measured weight before or at delivery minus early pregnancy weight (at <14 weeks' gestation), and standardised for gestational age into z-scores. We used Poisson regression to assess the association of gestational weight gain z-score with a composite outcome of: stillbirth, infant death, large for gestational age and small for gestational age at birth, preterm birth, unplanned caesarean delivery, gestational diabetes, pre-eclampsia, excess postpartum weight retention, and new-onset longer-term maternal cardiometabolic disease after pregnancy, weighted to account for event severity. We calculated rate ratios (RRs) for our composite adverse outcome along the weight gain z-score continuum, compared with a reference of the current lower limit for gestational weight gain recommended by the US Institute of Medicine (IOM; 5 kg at term). RRs were adjusted for confounding factors (maternal age, height, parity, early pregnancy BMI, early pregnancy smoking status, prepregnancy cardiovascular disease or diabetes, education, cohabitation status, and Nordic country of birth).

FINDINGS

Our cohort comprised 15 760 pregnancies with obesity, followed up for a median of 7·9 years (IQR 5·8-9·4). 11 667 (74·0%) pregnancies had class 1 obesity, 3160 (20·1%) had class 2 obesity, and 933 (5·9%) had class 3 obesity. Among these pregnancies, 1623 (13·9%), 786 (24·9%), and 310 (33·2%), respectively, had weight gain during pregnancy below the lower limit of the IOM recommendation (5 kg). In pregnancies with class 1 or 2 obesity, gestational weight gain values below the lower limit of the IOM recommendation or weight loss did not increase risk of the adverse composite outcome (eg, at weight gain z-score -2·4, corresponding to 0 kg at 40 weeks: adjusted RR 0·97 [95% CI 0·89-1·06] in obesity class 1 and 0·96 [0·86-1·08] in obesity class 2). In pregnancies with class 3 obesity, weight gain values below the IOM limit or weight loss were associated with reduced risk of the adverse composite outcome (eg, adjusted RR 0·81 [0·71-0·89] at weight gain z-score -2·4, or 0 kg).

INTERPRETATION

Our findings support calls to lower or remove the lower limit of current IOM recommendations for pregnant women with obesity, and suggest that separate guidelines for class 3 obesity might be warranted.

FUNDING

Karolinska Institutet and the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

Role of Nutritional Habits during Pregnancy in the Developing of Gestational Diabetes: A Single-Center Observational Clinical Study

(1) Background and Objective: Excessive gestational weight gain is associated with serious complications such as pre-eclampsia, fetal macrosomia and a more frequent need for cesarean section. The aim of this study is to develop a simple screening model that includes maternal age, BMI and nutritive habits in the second trimester in order to predict the risk of GDM in the population of pregnant women in the territory of the Republic of Serbia. (2) Materials and Methods: This single-center, prospective and case-control study was performed in the University Clinical Center "Dr. Dragisa Misovic Dedinje", Belgrade, Serbia and included 54 women with singleton pregnancies during the second trimester from July 2023 to November 2023. We used basic demographic and socio-epidemiological data, as well as data of the present comorbidities and previous pregnancies/births. The Serbian version of the Nutritive Status Questionnaire (NSQ) was used to estimate the nutritive habits in GDM (n = 22) and non-GDM groups (n = 32). (3) Results: We observed less frequent vegetable and fruit consumption in the GDM group in comparison with the non-GDM group; meat and chicken intake was 2-3 times per week in both groups; meat products were consumed 2-3 times per week in the GDM group and 2-3 times per month in the non-GDM group; milk products were consumed once a day in 31.8% of GDM patients and twice per day in 24.1% of non-GDM patients. Sweets (cakes, ice creams, biscuits) were consumed very often (2-3 times per week) in the GDM group (36.4%), while in the non-GDM group this habit was less frequent (26.7%). Cronbach alpha and internal consistency for this instrument were very good (Cronbach alpha = 0.87). (4) Conclusions: We have found that a non-adequate intake of fruits/vegetables, dairy and whole grain, as well as an excessive intake of sugar/artificially sweetened beverages and dairy, was associated with a higher risk of gestational diabetes mellitus (OR = 0.04; 95% CI).

Maternal risk factors for low birthweight and macrosomia: a cross-sectional study in Northern Region, Ghana

BACKGROUND

Abnormal birthweights are critical public health challenges accountable for most non-communicable diseases and perinatal mortalities. Regardless of the myriad of mixed evidence on maternal factors responsible for abnormal birthweight globally, most of these findings are attained from urban and rural settings. This study serves as one of the key pieces of evidence in view of the increasing prevalence of abnormal birthweight particularly in some parts of semi-rural Ghana. The study, therefore, aims to estimate the prevalence of abnormal birthweight and identify some possible maternal risk factors for abnormal birthweight in Northern Ghana.

METHODS

A retrospective cross-sectional study was conducted in Savelugu municipality from February-March 2022. A total of 356 mothers aged 16-46 years, having a neonate and attending postnatal care service, were recruited as study participants. Data were collected from maternal and child health record books and through structured interviews. To identify the maternal risk factors for abnormal birthweight, chi-square/Fischer's exact test and multinomial logistic regression were employed as bivariate and multivariate analyses, respectively, at 95% confidence level.

RESULTS

Prevalence rates of low birthweight and macrosomia were 22.2% and 8.7%, respectively. Maternal anaemia in first trimester (AOR 3.226; 95% CI 1.372-7.784) and third trimester (AOR 23.94; 95% CI 7.442-70.01) of gestation was strong predictors for low birthweight. Mothers belonging to minority ethnic groups (AOR 0.104; 95% CI 0.011-0.995); mothers who had ≥ 8 antenatal care visits (AOR 0.249; 95% CI 0.103-0.602); and mothers having neonates whose birth length > 47.5 cm (AOR 0.271; 95% CI 0.113-0.651) had reduced odds for low birthweight. Alternatively, mothers with gestational weeks ≥ 42 (AOR 23.21; 95% CI 4.603-56.19) and mothers from the richest households (highest socioeconomic homes) (AOR 14.25; 95% CI 1.638-23.91) were more likely to birth to macrosomic infants.

CONCLUSION

The prevalence rates of low birthweight and macrosomia were relatively high. Anaemia in the first and third trimesters was strong determinants of low birthweight. Being minority ethnic group, frequency of antenatal visits, and childbirth length reduced the risk of low-weight births. Advanced gestational age and socioeconomic status of mothers were also predictors of macrosomia. Hence, nutrition counselling, community health education, and promotion of lifestyle improvement coupled with strengthening of health service delivery are recommended interventions.

Low gestational weight gain (+2.0 to 4.9 kg) for singleton-term gestations associated with favorable perinatal outcomes for all prepregnancy obesity classes

BACKGROUND

Previous studies that evaluated low gestational weight gain or weight loss among prepregnancy obesity classes have not determined the amount of gestational weight gain associated with the lowest risk of adverse perinatal outcomes and neonatal morbidity among singleton term births.

OBJECTIVE

This study aimed to evaluate the relationship of specific gestational weight gain categories of weight loss, stable weight, and low gain considered below the 2009 Institute of Medicine guidelines to perinatal outcomes and neonatal morbidity for singleton, term live births among prepregnancy obesity classes.

STUDY DESIGN

This was a retrospective cohort study of 18,476 women among 3 classes of prepregnancy obesity, based on measured prepregnancy weight, and delivering a live singleton pregnancy at ≥37 weeks of gestation at a Kaiser Permanente Northern California hospital (2009-2012). Variables from electronic medical records included perinatal outcomes, sociodemographics, and measured prepregnancy and delivery weights to calculate total gestational weight gain, used to define 5 gestational weight gain categories: weight loss (<-2.0 kg), stable weight (-2.0 to +1.9 kg), low gain (+2.0 to 4.9 kg), gain within guidelines (+5.0 to 9.1 kg; referent), and gain above guidelines (>9.1 kg). Logistic regression models estimated adjusted odds ratios and 95% confidence intervals of maternal and newborn perinatal outcomes (hypertensive disorders, cesarean delivery, size for gestational age, length of stay, neonatal intensive care unit admission) associated with gestational weight gain categories stratified by prepregnancy obesity classes 1, 2, and 3.

RESULTS

Low gain occurred in 8%, 12%, and 13% of women in obesity class 1 (body mass index, 30.0-34.9), class 2 (body mass index, 35.0-39.9), and class 3 (body mass index, ≥40), respectively. Compared with gestational weight gain within Institute of Medicine guidelines, low gain was associated with similar or improved maternal and newborn perinatal outcomes for all obesity classes without increased odds of neonatal intensive care unit admission, neonatal length of stay ≥3 days, or small for gestational age. The percentages of small for gestational age for the low gain category were 4.4%, 3.0%, and 4.3% among prepregnancy obesity classes 1, 2, and 3, respectively, and comparable with the gestational weight gain within the guideline category (P>.05). The adjusted odds ratios of small-for-gestational age were not statistically significant for all obesity classes; class 1 (1.16; 95% confidence interval, 0.79-1.71) , class 2 (1.05; 95% confidence interval 0.58-1.93), and class 3 (2.03; 95% confidence interval 0.97-4.27).

CONCLUSION

Lower gestational weight gain of +2.0 to 4.9 kg showed the most favorable perinatal outcomes, without higher small for gestational age or neonatal morbidity for all obesity classes.

Prevalence and related factors of inappropriate gestational weight gain among pregnant women with overweight/ obesity in Thailand

BACKGROUND

An inappropriate gestational weight gain (GWG) among pregnant women with overweight/obesity is a crucial health problem. Its prevalence remains high worldwide, particularly in urban areas. The prevalence and predicting factors in Thailand are lack of evidence. This study aimed to investigate prevalence rates, antenatal care (ANC) service arrangement, predictive factors, and impacts of inappropriate GWG among pregnant women with overweight/obesity in Bangkok and its surrounding metropolitan area.

METHODS

This cross-sectional, retrospective study used four sets of questionnaires investigating 685 pregnant women with overweight/obesity and 51 nurse-midwives (NMs) from July to December 2019 in ten tertiary hospitals. Multinomial logistic regression identified predictive factors with a 95% confidence interval (CI).

RESULT

The prevalence rates of excessive and inadequate GWG were 62.34% and 12.99%. Weight management for pregnant women with overweight/obesity are unavailable in tertiary cares. Over three-fourths of NMs have never received weight management training for this particular group. ANC service factors, i.e., GWG counseling by ANC providers, quality of general ANC service at an excellent and good level, NMs' positive attitudes toward GWG control, significantly decreased the adjusted odds ratio (AOR) of inadequate GWG by 0.03, 0.01, 0.02, 0.20, times, respectively. While maternal factors, sufficient income, and easy access to low-fat foods reduce AOR of inadequate GWG by 0.49, and 0.31 times. In contrast, adequate maternal GWG knowledge statistically increased the AOR of inadequate GWG 1.81 times. Meanwhile, easy access to low-fat foods and internal weight locus of control (WLOC) decreased the AOR of excessive GWG by 0.29 and 0.57 times. Finally, excessive GWG significantly increased the risk of primary C/S, fetal LGA, and macrosomia 1.65, 1.60, and 5.84 times, respectively, while inadequate GWG was not associated with adverse outcomes.

CONCLUSION

Prevalence rates of inappropriate GWG, especially excessive GWG remained high and affected adverse outcomes. The quality of ANC service provision and appropriate GWG counseling from ANC providers are significant health service factors. Thus, NMs should receive gestational weight counseling and management training to improve women's knowledge and practice for gestational weight (GW) control.

Nausea and Vomiting during Early Pregnancy among Chinese Women and Its Association with Nutritional Intakes

Nausea and vomiting in pregnancy (NVP) is one of the most common uncomfortable symptoms of women in early pregnancy. A total of 303 Chinese pregnant women from 10 urban cities in their first trimester were recruited in this study to collect their sociodemographic characteristics and their NVP occurrence. Their dietary nutrient and food intakes were also collected by a 24 h dietary recall and a semi-quantitative food frequency questionnaire (SFFQ). Using the univariate analysis and multiple linear regression analysis to estimate the correlation between NVP and dietary intake, we found that 255 (84.1%) pregnant women experienced NVP during their first trimester. The intake of energy, protein, fat, vitamin A, thiamin, riboflavin, vitamin E, phosphorus, potassium, iron and zinc was lower in women with NVP than in those with no NVP. Additionally, women with NVP were more likely to have insufficient intake of protein, riboflavin, calcium, phosphorus and selenium. In terms of specific food groups, the average daily intake of mushrooms, algae, nuts and seeds, meat, eggs and dairy products in the NVP group was lower. Women in the severe NVP group even had insufficient gestational weight gain. We should pay more attention to women who experience nausea and vomiting during pregnancy and provide them with targeted nutritional support.

Gestational weight gain and neonatal outcomes in different zygosity twins: a cohort study in Wuhan, China

OBJECTIVE

To evaluate whether twin zygosity influences the association between neonatal outcomes and gestational weight gain (GWG) based on the Chinese guidelines in twin-pregnancy women.

DESIGN

A retrospective cohort study. And it is not a clinical trial.

SETTING

Women with twin pregnancies living in Wuhan, China.

PARTICIPANTS

A total of 5140 women who delivered live and non-malformed twins from 1 January 2011 to 31 August 2017 were included in this study.

MAIN OUTCOME MEASURE

The primary neonatal outcomes included paired small for gestational age (SGA, <10 th percentile birth weight for gestational age and sex), low birth weight (LBW, <2500 g) and gestational age (<33 weeks and <37 weeks). The association between GWG and neonatal outcomes was examined by Logistic regression analyses.

RESULTS

A total of 5140 women were included, of whom 22.24%, 54.78% and 22.98% were below, within and above the Chinese guidelines, respectively. Among the including 10 280 infants, 26.28% of them were monozygotic (MZ) twins and 73.72% of them were dizygotic (DZ) twins. Women with low GWG had a significantly higher proportion of LBW/LBW and LBW/NBW infants, a greater likelihood of SGA/SGA and SGA/appropriate for gestational age (AGA) infants and a higher incidence of preterm birth. The associations persisted both in MZ and DZ twins, and twin zygosity influenced the degree of association between GWG and SGA, LBW and preterm birth. High GWG was associated with significant risk reductions in SGA/AGA pairs, LBW/LBW or LBW/NBW pairs, and less than 33 gestational weeks. However, high GWG was only associated with reduced risk of LBW/LBW pairs both in MZ and DZ twins.

CONCLUSIONS

GWG below the Chinese recommendations increased the risk of SGA, LBW and preterm birth in both MZ and DZ twins. The effect was more pronounced in MZ twins than that in DZ twin pairs. A high GWG only reduced the risk of LBW/LBW pairs both in MZ and DZ twins.

Gestational Weight Gain and Small for Gestational Age in Obese Women: A Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review and meta-analysis evaluates the relationship between gestational weight gain and the risk of small for gestational age in obese pregnant women.

METHODS

Studies were identified by searching the Web of Science, Embase, and PubMed databases up to June 30th, 2022. The meta-analysis was carried out to determine the risk of small for gestational age with gestational weight gain (GWG) below the 2009 Institute of Medicine (IOM) guidelines compared with within the guidelines in obese women. The Newcastle-Ottawa Scale was used to assess the methodological quality. The chi-squared test, Q test, and I² test were used to evaluate statistical heterogeneity. Subgroup analyses were conducted, and publication bias was assessed by funnel plots and Egger's test. Sensitivity analyses were performed for three groups of obese people (I: BMI 30-34.9 kg/m², II: BMI 35-39.9 kg/m², and III: BMI ≥ 40 kg/m²) to examine the association of obesity and SGA.

RESULTS

A total of 788 references were screened, and 29 studies (n = 1242420 obese women) were included in the systematic review. Obese women who gained weight below the IOM guideline had a higher risk of SGA than those who gained weight within the guideline (OR = 1.27, 95% CI = 1.16-1.38, Z = 5.36). Both weight loss (<0 kg) and inadequate weight (0-4.9 kg) during pregnancy in obese women are associated with an increased risk of SGA (OR = 1.50, 95% CI = 1.37-1.64, Z = 8.82) (OR = 1.18, 95% CI = 1.14-1.23, Z = 8.06). The same conclusions were also confirmed for the three obesity classes (I: OR = 1.38, 95% CI = 1.29-1.47; II: OR = 1.39, 95% CI = 1.30-1.49; and III: OR = 1.26, 95% CI = 1.16-1.37). Subgroup analysis by country showed that GWG below guidelines in obese women of the USA and Europe was associated with risk for SGA (USA (OR = 1.30, 95% CI = 1.15-1.46), Europe (OR = 1.24, 95% CI = 1.11-1.40)) and not in Asia (OR = 1.17, 95% CI = 0.91-1.50).

CONCLUSION

Our findings indicated that obese pregnant women who had weight loss or inadequate weight (0-4.9 kg) according to the IOM guideline had increased risks for SGA. Moreover, we also evaluated that gestational weight loss (<0 kg) in these pregnancies was associated with an increased risk for SGA compared with inadequate weight (0-4.9 kg) in these pregnancies. Therefore, the clinical focus should assist obese women to achieve GWG within the IOM guidelines to decrease the risk for SGA.

Vitamin D Deficiency, Excessive Gestational Weight Gain, and Oxidative Stress Predict Small for Gestational Age Newborns Using an Artificial Neural Network Model

(1) Background: Size at birth is an important early determinant of health later in life. The prevalence of small for gestational age (SGA) newborns is high worldwide and may be associated with maternal nutritional and metabolic factors. Thus, estimation of fetal growth is warranted. (2) Methods: In this work, we developed an artificial neural network (ANN) model based on first-trimester maternal body fat composition, biochemical and oxidative stress biomarkers, and gestational weight gain (GWG) to predict an SGA newborn in pregnancies with or without obesity. A sensibility analysis to classify maternal features was conducted, and a simulator based on the ANN algorithm was constructed to predict the SGA outcome. Several predictions were performed by varying the most critical maternal features attained by the model to obtain different scenarios leading to SGA. (3) Results: The ANN model showed good performance between the actual and simulated data (R² = 0.938) and an AUROC of 0.8 on an independent dataset. The top-five maternal predictors in the first trimester were protein and lipid oxidation biomarkers (carbonylated proteins and malondialdehyde), GWG, vitamin D, and total antioxidant capacity. Finally, excessive GWG and redox imbalance predicted SGA newborns in the implemented simulator. Significantly, vitamin D deficiency also predicted simulated SGA independently of GWG or redox status. (4) Conclusions: The study provided a computational model for the early prediction of SGA, in addition to a promising simulator that facilitates hypothesis-driven constructions, to be further validated as an application.

Recurrent gestational diabetes : Breaking the transgenerational cycle with lifestyle modification

PURPOSE

This literature review is aimed at examining the benefits of lifestyle modifications in preventing recurrent gestational diabetes (GDM). Worldwide GDM affects approximately 16.2% of all pregnancies with significant maternal, fetal and neonatal complications. Almost two thirds of pregnant women with GDM will develop type 2 diabetes mellitus (T2DM) in the years following pregnancy. The proportion of women affected by GDM is on the rise and reflects increasing trends in T2DM as well as adult and childhood obesity.

METHODS

Using predefined subject headings, we searched for relevant articles from the PubMed, Scopus, and Cochrane databases.

RESULTS

For high-risk women lifestyle modifications, such as dietary and exercise changes, are the mainstay of treatment to reduce negative outcomes for both women and their pregnancies. This includes reducing the incidence of recurrent GDM and future T2DM by intervening during pregnancy and in the postnatal period.

CONCLUSION

This review provides an overview of the literature to date, discusses different targeted approaches and how these interventions can optimise their benefits, and where further research is required.

Investigation of optimal gestational weight gain based on the occurrence of adverse pregnancy outcomes for Chinese women: a prospective cohort study

OBJECTIVE

To investigate recommendations for appropriate gestational weight gain (GWG) of Chinese females.

METHODS

In total of 3,172 eligible women in the first trimester were recruited into the Chinese Pregnant Women Cohort Study (CPWCS) project. Pregnancy complications and outcomes were collated using the hospital medical records system. The method of occurrence of participants with adverse pregnancy outcomes (Occurrence Method) was conducted to calculate the recommended total GWG for each participant's pre-pregnancy BMI. Occurrence Method data were judged against the Institute of Medicine (IOM) and Japanese recommended criteria in terms of the total occurrence of adverse pregnancy outcomes of pregnant women with appropriate weight gain.

RESULTS

The most frequent GWG was ≥ 14 kg and < 16 kg (19.4%), followed by ≥ 10 kg and < 12 kg (15.5%) and ≥ 12 kg and < 14 kg (15.2%). The most frequently occurring adverse pregnancy outcomes were cesarean sections for underweight (30.0%), normal weight (40.4%), overweight (53.6%) and obese (53.7%) women. A large for gestational age (LGA) accounted for 18.0% of the overweight and 20.9% of the obesity group. Gestational diabetes mellitus (GDM) occurred in 16.9% of overweight and 23.1% of obese women. The recommended total GWG in a Chinese women population is ≥ 8 and < 12 kg if underweight, ≥ 12 and < 14 kg for normal weight, ≥ 8.0 and < 10.0 kg if overweight, and < 8 kg for women with obesity.

CONCLUSIONS

Current Chinese recommendations provide the optimal ranges of GWG to minimize the occurrence of undesirable pregnancy outcomes for each group of pre-pregnancy BMIs in a Chinese population.

TRIAL REGISTRATION

Registered with ClinicalTrials ( NCT03403543 ).

Maternal Weight Gain and Infant Birth Weight in Women with Class III Obesity

OBJECTIVE

The aim of this study is to describe the impact of maternal weight gain on infant birth weight among women with Class III obesity.

STUDY DESIGN

Retrospective cohort of women with body mass index (BMI) ≥40 kg/m² at initial prenatal visit, delivered from July 2013 to December 2017. Women presenting 14/0 weeks of gestational age (GA), delivering preterm, or had multiples or major fetal anomalies excluded. Maternal demographics and complications, intrapartum events, and neonatal outcomes abstracted. Primary outcomes were delivery of large for gestational age or small for gestational age (SGA) infant. Bivariate statistics used to compare women gaining less than Institute of Medicine (IOM) recommendations (LTR) and women gaining within recommendations (11-20 pounds/5-9.1 kg) (at recommended [AR]). Regression models used to estimate odds of primary outcomes.

RESULTS

Of included women (n = 230), 129 (56%) gained LTR and 101 (44%) gained AR. In sum, 71 (31%) infants were LGA and 2 (0.8%) were SGA. Women gaining LTR had higher median entry BMI (46 vs. 43, p < 0.01); other demographics did not differ. LTR women were equally likely to deliver an LGA infant (29 vs. 34%, p = 0.5) but not more likely to deliver an SGA infant (0.8 vs. 1%, p > 0.99). After controlling for confounders, the AOR of an LGA baby for LTR women was 0.79 (95% CI: 0.4-1.4).

CONCLUSION

In this cohort of morbidly obese women, gaining less than IOM recommendations did not impact risk of having an LGA infant, without increasing risk of an SGA infant.

Risk factors for pregnancy outcomes in Type 1 and Type 2 diabetes

BACKGROUND

Understanding the risk factors and pregnancy outcomes in women affected by Type 1 and Type 2 diabetes is important for pre-pregnancy counselling.

AIM

To explore differences in pregnancy outcomes between women with Type 1 and Type 2 diabetes, and healthy controls, and to examine the relationships between potential adverse risk factors and pregnancy outcomes in this cohort of women.

METHODS

This is a 10-year retrospective study of women with Type 1 diabetes (n = 92), Type 2 diabetes (n = 106) and healthy women without diabetes (controls) (n = 119) from a tertiary obstetric centre. Clinical and biochemical characteristics of women with Type 1 and Type 2 diabetes were determined and related to major obstetric outcomes using univariate analysis.

RESULTS

Women with pre-existing diabetes had higher adverse pregnancy outcomes (preeclampsia, emergency caesarean section, preterm birth <32 and 37 weeks, large for gestational age, neonatal jaundice, Apgar score < 7 at 5 min, neonatal intensive care admission and neonatal hypoglycaemia) compared to controls. A higher birth weight gestational centile (97.4% vs 72.4%, P = 0.001) and large for gestational age rate (63.4% vs 35.8%, P = 0.001) were observed in Type 1 diabetes compared to Type 2 diabetes. There were no differences in other outcomes between women with Type 1 and 2 diabetes.

CONCLUSION

In this exploratory study, risk factors for maternal adverse outcomes differ between Type 1 and Type 2 diabetes. Maternal and foetal adverse outcomes were higher in pregnancies affected by diabetes compared to healthy women but occurred with similar frequency in women with Type 1 and Type 2 diabetes.

Association between maternal gestational weight gain and preterm birth according to body mass index and maternal age in Quzhou, China

The aim of this study is to investigate the association between maternal gestational weight gain (GWG) and preterm birth according to pre-pregnancy body mass index (BMI) and maternal age. We did a cohort, hospital-based study in Quzhou, South China, from 1 Jan 2018 to 30 June 2019. We selected 4274 singleton live births in our analysis, 315 (7.4%) of which were preterm births. In the overall population, excess GWG was significantly associated with a decreased risk of preterm birth compared with adequate GWG (adjusted OR 0.81 [95% CI 0.72-0.91]), and the risk varied by increasing maternal age and pre-pregnancy BMI. Interestingly, underweight women who older than 35 years with excess GWG had significantly increased odds of preterm birth compared with adequate GWG in underweight women aged 20-29 years (2.26 [1.06-4.85]) and normal weight women older than 35 years (2.23 [1.13-4.39]). Additionally, low GWG was positively and significantly associated with preterm birth overall (1.92 [1.47-2.50]). Among normal weight women category, compared with adequate GWG women aged 20-29 years did, those older than 20 years with low GWG, had significantly higher odds of preterm birth, which increased with maternal age (1.80 [1.16-2.79] in 20-29 years, 2.19 [1.23-3.91] in 30-34 years, 3.30 [1.68-6.46] in ≫ 35 years). In conclusion, maternal GWG was significantly associated with the risk of preterm birth, but the risk varied by pre-pregnancy BMI and maternal age.

Exploration of the Vaginal and Gut Microbiome in African American Women by Body Mass Index, Class of Obesity, and Gestational Weight Gain: A Pilot Study

OBJECTIVE

This study determines the differences in the distal gut and vaginal microbiome in African American (AA) women by prepregnancy body mass index and gestational weight gain (GWG) comparing women with and without obesity and by obesity class.

STUDY DESIGN

We prospectively sampled the vaginal and distal gut microbiome in pregnant AA women at two time points during pregnancy. Samples were analyzed using high-throughput sequencing of the V4 region of the 16S ribosomal ribonucleic acid gene.

RESULTS

Distinct differences in vaginal and distal gut α-diversity were observed at time point 1 between women with and without obesity by total GWG. Significant differences in distal gut β-diversity were also found at time point 1 in obese women by GWG. Within the Bacteroides genus, a significant association was observed by total GWG among obese women which was absent in nonobese women. Women with class III obesity who experienced low GWG had the lowest abundance of distal gut Bacteroides and appreciably higher relative abundance of a consortia of vaginal taxa including Atopobium, Gardnerella, Prevotella, and Sneathia.

CONCLUSION

These results contribute new evidence showing that GWG in combination with obesity and obesity class is associated with an altered distal gut and vaginal composition early in pregnancy among AA women.

The impact of excessive gestational weight gain timing on neonatal outcomes in women with class III obesity

OBJECTIVE

This study evaluated the influence of early gestational weight gain (GWG) on neonatal outcomes among women with class III obesity.

STUDY DESIGN

Retrospective cohort of women with class III obesity who gained more than the Institute of Medicine (IOM) guidelines (>20lbs). Women gaining ≥75% of total gestational weight prior to 28 weeks (EWG) were compared to women gaining <75% of their total weight prior to 28 weeks (SWG). The primary outcome was a neonatal composite morbidity and mortality. Secondary outcomes included individual components of composite and LGA.

RESULTS

Of 144 women identified, 42 (29.2%) had EWG and 102 (70.8%) had SWG. Though 11% of the total population had composite neonatal morbidity, this did not differ between groups (p = .4). LGA was nearly twice as common in the SWG group (41% vs 26%, p = .13). EWG was associated with decreased risk of LGA (AOR 0.25 95% CI 0.08, 0.78) and lower median birth weight (AOR -312 g 95% CI -534.7, -90.2).

CONCLUSION

Though adverse neonatal outcomes were common in this population, timing of gestational weight gain was not correlated. Increased rates of LGA and higher median birth weight in the SWG group suggests excessive GWG continuing in the third trimester of pregnancy may be of import for neonatal size.

Association of provider advice and gestational weight gain in twin pregnancies: a cross-sectional electronic survey

BACKGROUND

Little is known about patient-provider communication on gestational weight gain among women pregnant with twins, a growing population at high risk for adverse maternal and neonatal outcomes. We examined if women's report of provider advice on gestational weight gain was consistent with the Institute of Medicine (IOM) weight gain guidelines for twin pregnancies, and the association of provider advice on weight gain with women's weight gain during their twin pregnancy.

METHODS

We conducted a cross-sectional survey of 276 women who delivered twins and received prenatal care in the United States. The 2009 IOM provisional weight gain guidelines for twin pregnancies defined whether provider advice on weight gain and women's weight gain were below, within, or above guidelines. Multinomial logistic regression examined associations between provider advice on weight gain with women's weight gain, after adjustment for maternal age, gestational age at delivery, education, parity, twin type, use of assisted reproductive technologies and pre-pregnancy BMI category.

RESULTS

Approximately 30% of women described provider advice on weight gain below the IOM guidelines, 60% within, and 10% above guidelines. Compared to women who reported weight gain advice within guidelines, women who reported advice below guidelines or who reported no advice were 7.1 (95% CI: 3.2, 16.0) and 2.7 (95% CI: 1.3, 5.6) times more likely to gain less than recommended, respectively. Women who reported provider advice above guidelines were 4.6 (95% CI: 1.5, 14.2) times more likely to exceed guidelines.

CONCLUSIONS

Provider advice on gestational weight gain may be an important predictor of women's weight gain during twin pregnancies, highlighting the critical need for accurate provider counseling to optimize health outcomes.

Effects of pre-pregnancy body mass index and gestational weight gain on maternal and infant complications

Background

The potential effects of pre-pregnancy body mass (BMI) and gestational weight gain (GWG) on pregnancy outcomes remain unclear. Thus, we investigated socio-demographic characteristics that affect pre-pregnancy BMIs and GWG and the effects of pre-pregnancy BMI and GWG on Chinese maternal and infant complications.

Methods

3172 women were enrolled in the Chinese Pregnant Women Cohort Study-Peking Union Medical College from July 25, 2017 to July 24, 2018, whose babies were delivered before December 31, 2018. Regression analysis was employed to evaluate the socio-demographic characteristics affecting pre-pregnancy BMI and GWG values and their effects on adverse maternal and infant complications.

Results

Multivariate logistic regression analysis revealed that age groups < 20 years (OR: 1.97), 25–30 years (OR: 1.66), 30–35 years (OR: 2.24), 35–40 years (OR: 3.90) and ≥ 40 years (OR: 3.33) as well as elementary school or education below (OR: 3.53), middle school (OR: 1.53), high school (OR: 1.40), and living in the north (OR: 1.37) were risk factors in maintaining a normal pre-pregnancy BMI. An age range of 30–35 years (OR: 0.76), living in the north (OR: 1.32) and race of ethnic minorities (OR: 1.51) were factors affecting GWG. Overweight (OR: 2.01) and inadequate GWG (OR: 1.60) were risk factors for gestational diabetes mellitus (GDM). Overweight (OR: 2.80) and obesity (OR: 5.42) were risk factors for gestational hypertension (GHp). Overweight (OR: 1.92), obesity (OR: 2.48) and excessive GWG (OR: 1.95) were risk factors for macrosomia. Overweight and excessive GWG were risk factors for a large gestational age (LGA) and inadequate GWG was a risk factor for low birth weights.

Conclusions

Overweight and obesity before pregnancy and an excessive GWG are associated with a greater risk of developing GDM, GHp, macrosomia and LGA. The control of body weight before and during the course of pregnancy is recommended to decrease adverse pregnancy outcomes, especially in pregnant women aged < 20 or > 25 years old educated below university and college levels, for ethnic minorities and those women who live in the north of China.

Trial registration

Registered at Clinical Trials (NCT03403543), September 29, 2017.

A low intensity dietary intervention for reducing excessive gestational weight gain in an overweight and obese pregnant cohort

PURPOSE

Excessive gestational weight gain is associated with detrimental outcomes to both the mother and baby. Currently, the best approach to prevent excessive gestational weight gain in overweight and obese women is undetermined. The present study aimed to evaluate the effectiveness of a group-based outpatient dietary intervention in pregnancy to reduce excessive gestational weight gain.

METHODS

In this retrospective study, overweight and obese pregnant women who attended a single 90-min group education session were compared to women who received standard care alone. Total gestational weight gain, maternal and neonatal outcomes were compared between the intervention and control groups. Data were analysed using Student t, Mann-Whitney and Chi-squared tests as appropriate. A 24-h dietary recall was analysed and compared to the Australian National Nutrition Survey.

RESULTS

A significant reduction in gestational weight gain was observed with this intervention (P = 0.010), as well as in the rate of small for gestational age births (P = 0.043). Those who attended the intervention had saturated fat and sodium intake levels that exceeded recommendations. Intake of pregnancy-specific micronutrients including folate, calcium and iron were poor from diet alone.

CONCLUSIONS

A low-intensity antenatal dietary intervention may be effective in reducing excessive gestational weight gain, although multi-disciplinary interventions yield the best success. Further research is required to identify the optimal modality and frequency to limit excessive gestational weight gain. Dietary interventions tailored to ethnicity should also be explored.

LEVEL OF EVIDENCE

Level II, controlled trial without randomization.

Rate of gestational weight gain and adverse pregnancy outcomes in rural nulliparous women: a prospective cohort analysis from China

Both inadequate and excessive gestational weight gain (GWG) have been shown to increase the risk of adverse pregnancy outcomes, but the risk profiles of GWG rate are unclear. We aimed to examine the associations between GWG rate in the second/third trimester and a spectrum of pregnancy outcomes. This study consisted of 14 219 Chinese rural nulliparous women who participated in a randomised controlled trial of prenatal micronutrient supplementation during 2006–2009. The outcomes included stillbirth, neonatal and infant death, preterm birth, macrosomia, low birth weight (LBW) and large and small for gestational age (LGA and SGA, respectively). GWG rate was divided into quintiles within each BMI category. Compared with women in the middle quintile, those in the lowest quintile had higher risks of neonatal death (adjusted OR 2·27; 95 % CI 1·03, 5·02), infant death (adjusted OR 1·85; 95 % CI 1·02, 3·37) and early preterm birth (adjusted OR 2·33; 95 % CI 1·13, 4·77), while those in the highest quintile had higher risks of overall preterm birth (adjusted OR 1·28; 95 % CI 1·04, 1·59), late preterm birth (adjusted OR 1·25; 95 % CI 1·00, 1·56), LBW (adjusted OR 1·48; 95 % CI 1·02, 2·15), macrosomia (adjusted OR 1·89; 95 % CI 1·46, 2·45) and LGA (adjusted OR 1·56; 95 % CI 1·31, 1·85). In conclusion, very low and very high GWG rates in the second/third trimester appear to be associated with adverse pregnancy outcomes in Chinese nulliparous women, indicating that an appropriate GWG rate during pregnancy is necessary for neonatal health.

Guidelines for Medical Nutrition Therapy in Gestational Diabetes Mellitus: Systematic Review and Critical Appraisal

BACKGROUND

Medical nutrition therapy is the cornerstone of gestational diabetes mellitus treatment. However, guidelines often present contradictory guidance to health care practitioners.

OBJECTIVE

To systematically review and critically appraise medical nutrition therapy guidelines for treating patients with gestational diabetes mellitus.

DESIGN

We searched Medline, the Cochrane Library, Guidelines International Network, and Google Scholar to retrieve clinical practice guidelines (CPGs) for medical nutrition therapy in gestational diabetes mellitus from professional or governmental organizations, published in English, between January 1, 2007, and November 24, 2018. CPGs were reviewed and appraised using the Appraisal of Guidelines, Research, and Evaluation II instrument.

RESULTS

Of 1,286 retrieved articles, 21 CPGs fulfilled the inclusion criteria. CPGs of the Academy of Nutrition and Dietetics, Diabetes Canada, and Malaysia Health Technology Assessment Section received the greatest overall scores and the highest scores concerning rigor of recommendations development. Many CPGs failed to involve multidisciplinary teams in their development, including patients, and often, dietitians. Applicability of the recommendations was low, lacking facilitators and tools to enhance implementation. Many CPGs demonstrated low editorial independence by failing to disclose funding and competing interests. More medical nutrition therapy recommendations were incorporated in the Academy of Nutrition and Dietetics and Malaysia Health Technology Assessment Section CPGs. The Malaysia Health Technology Assessment Section, Diabetes Canada, Academy of Nutrition and Dietetics, and Endocrine Society guidelines were recommended by the review panel herein without modifications. Overall, the CPGs suggested the consumption of adequate protein and the selection of foods with low glycemic index, divided into three main meals and two to four snacks. Weight gain recommendations were mostly based on the Institute of Medicine body mass index thresholds.

CONCLUSIONS

With few exceptions, the main developmental limitations of the appraised CPGs involved low rigor of recommendations development, lack of multidisciplinary stakeholder involvement, low applicability, and inadequate editorial independence. This indicates a need for developing more clear, unbiased, practical, and evidence-based CPGs.

Association of trimester-specific gestational weight gain with birth weight and fetal growth in a large community-based population

BACKGROUND

Previous studies showed that the association of gestational weight gain (GWG) with fetal birthweight and offspring developmental growth was unclear. The aim of this study is to investigate the respective effect of 1 kg of GWG during three trimesters on birthweight and offspring growth from birth to 3 years of age.

METHODS

We extracted the decoded information from the Maternal and Child Health Information Management System of Zhoushan Maternal and Child Health Hospital in Zhejiang, China from October 2001 to March 2015, and used multiple linear and logistic regression models.

RESULTS

This study included 20,232 women with a full-term singleton birth and 15,557 newborns who took regular health check-ups. Compared to that in the 2nd and 3rd trimester, 1 kg GWG increasing in the 1st trimester had the strongest positive association with higher birthweight, body weight, and height from 1 to 36 months. Their associations with BMI after birth were similar among the three trimesters. In addition, some positive dose-response effects found between quartiles of GWG in the 1st trimester and offspring body weight, as well as BMI. The 1 kg GWG in 1st trimester played the strongest role in contributing to birth weight and benefiting to body growth among children aged up to 3 years.

CONCLUSION

The 1 kg GWG in 1st trimester contributed more to birth weight and body development from birth to 3 years compared to the 2nd and 3rd trimesters. The possible beneficial effects of GWG in the 1st trimester on birthweight and offspring development in under/normal weight mothers are found.

Improving outcomes in gestational diabetes: does gestational weight gain matter?

AIM

Excessive gestational weight gain increases risk of gestational diabetes mellitus (GDM) but it remains unclear whether weight control after GDM diagnosis improves outcomes. We assessed whether: (1) total gestational weight gain during pregnancy (0-36 weeks); (2) early gestational weight gain (0-28 weeks, before GDM diagnosis); or (3) late gestational weight gain (28-36 weeks, after diagnosis) are associated with maternal-fetal outcomes.

METHODS

Some 546 women with GDM who delivered viable singleton infants at a single UK obstetric centre (October 2014 to March 2017) were included in this retrospective observational study.

RESULTS

Higher total gestational weight gain was associated with Caesarean section [n = 376; odds ratio (OR) 1.05; confidence intervals (CI) 1.02-1.08, P < 0.001] and large for gestational age (OR 1.08; CI 1.03-1.12, P < 0.001). Higher late gestational weight gain (28-36 weeks; n = 144) was associated with large for gestational age (OR 1.17; CI 1.01-1.37, P < 0.05), instrumental deliveries (OR 1.26; CI 1.03-1.55, P < 0.01), higher total daily insulin doses (36 weeks; beta coefficient 4.37; CI 1.92-6.82, P < 0.001), and higher post-partum 2-h oral glucose tolerance test concentrations (beta coefficient 0.12; CI 0.01-0.22, P < 0.05). Women who avoided substantial weight gain after GDM diagnosis had 0.7 mmol/l lower postnatal 2-h glucose and needed half the amount of insulin/day at 36 weeks compared with women with substantial weight gain after diagnosis. There were no significant associations between early gestational weight gain (0-28 weeks) and pregnancy outcomes.

CONCLUSIONS

These findings suggest that controlling gestational weight gain should be a priority following GDM diagnosis to optimize pregnancy outcomes and improve maternal postnatal glucose homeostasis. The period after diagnosis of GDM (often 28 weeks gestation) is not too late to offer lifestyle advice or intervention to improve weight management and pregnancy outcomes.

Reprint of characterizing gestational weight gain in a cohort of indigenous Australian women

OBJECTIVE

to determine the adequacy of gestational weight gain for a cohort of Indigenous Australian women and investigate whether it is associated with pre-pregnancy body mass index.

DESIGN

analysis of observational data collected from a longitudinal cohort study that follows Indigenous Australian women through pregnancy.

SETTING

women recruited through antenatal clinics in regional and remote towns in NSW, Australia to the Gomeroi gaaynggal program.

PARTICIPANTS

110 pregnant women who either identified as being an Indigenous Australian or as carrying an Indigenous child.

MEASUREMENTS AND FINDINGS

measurements included weight and height, self-reported pre-pregnancy weight and smoking status, parity and health conditions that may contribute to gestational weight gain, such as hypertensive or diabetic disorders. Compared to the 2009 Institute of Medicine recommendations for gestational weight gain and based on pre-pregnancy body mass index, the rate of adequate gestational weight gain in this cohort was low (26%). 33% of women had inadequate weight gain and 41% had excessive weight gain. The highest rate of excessive gestational weight gain was found in overweight women (65%), with rates of 39% and 31% found in healthy and obese (all classes) categories, respectively. Parity (coefficient 4.2, p < 0.01) and hypertension (coefficient 4.3, p = 0.049) were found to be significantly associated with gestational weight gain in mixed model linear regression.

CONCLUSIONS

few women gained adequate gestational weight gain in this study. Culturally acceptable ways of addressing this issue are needed for this group of women, as inadequate and excessive rates of gestational weight gain have health implications for women and their offspring.

IMPLICATIONS FOR PRACTICE

a systematic approach to addressing gestational weight gain within antenatal care is required, including asking about diet and exercise, for all women identifying as Indigenous Australian.

Lifestyle Interventions Limit Gestational Weight Gain in Women with Overweight or Obesity: LIFE-Moms Prospective Meta-Analysis

OBJECTIVE

This study aimed to evaluate the effects of varied lifestyle intervention programs designed to ameliorate excess gestational weight gain (GWG) in pregnant women with overweight or obesity compared with standard care, including effects on pregnancy outcomes.

METHODS

Seven clinical centers conducted separate randomized clinical trials to test different lifestyle intervention strategies to modify GWG in diverse populations. Eligibility criteria, specific outcome measures, and assessment procedures were standardized across trials. The results of the separate trials were combined using an individual-participant data meta-analysis.

RESULTS

For the 1,150 women randomized, the percent with excess GWG per week was significantly lower in the intervention group compared with the standard care group (61.8% vs. 75.0%; odds ratio [95% CI]: 0.52 [0.40 to 0.67]). Total GWG from enrollment to 36 weeks' gestation was also lower in the intervention group (8.1 ± 5.2 vs. 9.7 ± 5.4 kg; mean difference: -1.59 kg [95% CI:-2.18 to -0.99 kg]). The results from the individual trials were similar. The intervention and standard care groups did not differ in preeclampsia, gestational diabetes, cesarean delivery, or birth weight.

CONCLUSIONS

Behavioral lifestyle interventions focusing primarily on diet and physical activity among women with overweight and obesity resulted in a significantly lower proportion of women with excess GWG. This modest beneficial effect was consistent across diverse intervention modalities in a large, racially and socioeconomically diverse US population of pregnant women.

Gestational Weight Gain per Pre-Pregnancy Body Mass Index and Birth Weight in Twin Pregnancies: A Cohort Study in Wuhan, China

To assess the relationship between gestational weight gain (GWG) of twin-pregnancy women and twin birth weights, as well as to evaluate whether pre-pregnancy body mass index (BMI) influences this relationship. A cohort study was conducted in Wuhan, China, between 1/01/2011 and 8/31/2017. Women with twin pregnancies who delivered live and non-malformed twins were included (6,925 women and 13,850 infants), based on the Wuhan Maternal and Child Health Management Information System. Logistic regression models were employed to examine the association between GWG and paired small for gestational age (SGA, defined as birth weight <10th percentile for gestational age and sex)/SGA and linear regression models were utilized to explore the relationship between GWG and sum of birth weights. The associations of GWG based on both the IOM and Chinese recommendations and SGA/SGA pairs were obtained, as well as the stratified analyses by pre-pregnancy BMI. Additionally, the sum birth weight of one twin pair increased by 15.88 g when the GWG increased by 1 kg. GWG below the IOM and Chinese recommendations was associated with an increased risk of SGA/SGA pairs in all pre-pregnancy BMI categories. However, in underweight, overweight, and obese women, the association between GWG above the IOM and Chinese recommendations and SGA/SGA pairs changed with adjustment.

Characterizing gestational weight gain in a cohort of Indigenous Australian women

OBJECTIVE

to determine the adequacy of gestational weight gain for a cohort of Indigenous Australian women and investigate whether it is associated with pre-pregnancy body mass index.

DESIGN

analysis of observational data collected from a longitudinal cohort study that follows Indigenous Australian women through pregnancy.

SETTING

women recruited through antenatal clinics in regional and remote towns in NSW, Australia to the Gomeroi gaaynggal program.

PARTICIPANTS

110 pregnant women who either identified as being an Indigenous Australian or as carrying an Indigenous child.

MEASUREMENTS AND FINDINGS

measurements included weight and height, self-reported pre-pregnancy weight and smoking status, parity and health conditions that may contribute to gestational weight gain, such as hypertensive or diabetic disorders. Compared to the 2009 Institute of Medicine recommendations for gestational weight gain and based on prepregnancy body mass index, the rate of adequate gestational weight gain in this cohort was very low (15%). 32% of women had inadequate weight gain and 54% had excessive weight gain. The highest rate of excessive gestational weight gain was found in overweight women (74%), with rates of 48% and 50% found in healthy and obese (all classes) categories, respectively. Parity (coefficient 4.5, p<0.01) and hypertension (coefficient 4.8, p = 0.04) were found to be significantly associated with gestational weight gain in mixed model linear regression.

CONCLUSIONS

few women gained adequate gestational weight gain in this study. Culturally acceptable ways of addressing this issue are needed for this group of women, as inadequate and excessive rates of gestational weight gain have health implications for women and their offspring.

IMPLICATIONS FOR PRACTICE

a systematic approach to addressing gestational weight gain within antenatal care is required, including asking about diet and exercise, for all women identifying as Indigenous Australian.

Association of Gestational Weight Gain With Maternal and Infant Outcomes: A Systematic Review and Meta-analysis

IMPORTANCE

Body mass index (BMI) and gestational weight gain are increasing globally. In 2009, the Institute of Medicine (IOM) provided specific recommendations regarding the ideal gestational weight gain. However, the association between gestational weight gain consistent with theIOM guidelines and pregnancy outcomes is unclear.

OBJECTIVE

To perform a systematic review, meta-analysis, and metaregression to evaluate associations between gestational weight gain above or below the IOM guidelines (gain of 12.5-18 kg for underweight women [BMI <18.5]; 11.5-16 kg for normal-weight women [BMI 18.5-24.9]; 7-11 kg for overweight women [BMI 25-29.9]; and 5-9 kg for obese women [BMI ≥30]) and maternal and infant outcomes.

DATA SOURCES AND STUDY SELECTION

Search of EMBASE, Evidence-Based Medicine Reviews, MEDLINE, and MEDLINE In-Process between January 1, 1999, and February 7, 2017, for observational studies stratified by prepregnancy BMI category and total gestational weight gain.

DATA EXTRACTION AND SYNTHESIS

Data were extracted by 2 independent reviewers. Odds ratios (ORs) and absolute risk differences (ARDs) per live birth were calculated using a random-effects model based on a subset of studies with available data.

MAIN OUTCOMES AND MEASURES

Primary outcomes were small for gestational age (SGA), preterm birth, and large for gestational age (LGA). Secondary outcomes were macrosomia, cesarean delivery, and gestational diabetes mellitus.

RESULTS

Of 5354 identified studies, 23 (n = 1 309 136 women) met inclusion criteria. Gestational weight gain was below or above guidelines in 23% and 47% of pregnancies, respectively. Gestational weight gain below the recommendations was associated with higher risk of SGA (OR, 1.53 [95% CI, 1.44-1.64]; ARD, 5% [95% CI, 4%-6%]) and preterm birth (OR, 1.70 [1.32-2.20]; ARD, 5% [3%-8%]) and lower risk of LGA (OR, 0.59 [0.55-0.64]; ARD, -2% [-10% to -6%]) and macrosomia (OR, 0.60 [0.52-0.68]; ARD, -2% [-3% to -1%]); cesarean delivery showed no significant difference (OR, 0.98 [0.96-1.02]; ARD, 0% [-2% to 1%]). Gestational weight gain above the recommendations was associated with lower risk of SGA (OR, 0.66 [0.63-0.69]; ARD, -3%; [-4% to -2%]) and preterm birth (OR, 0.77 [0.69-0.86]; ARD, -2% [-2% to -1%]) and higher risk of LGA (OR, 1.85 [1.76-1.95]; ARD, 4% [2%-5%]), macrosomia (OR, 1.95 [1.79-2.11]; ARD, 6% [4%-9%]), and cesarean delivery (OR, 1.30 [1.25-1.35]; ARD, 4% [3%-6%]). Gestational diabetes mellitus could not be evaluated because of the nature of available data.

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis of more than 1 million pregnant women, 47% had gestational weight gain greater than IOM recommendations and 23% had gestational weight gain less than IOM recommendations. Gestational weight gain greater than or less than guideline recommendations, compared with weight gain within recommended levels, was associated with higher risk of adverse maternal and infant outcomes.