Pre-pregnancy body mass index and weight gain during pregnancy: relations with gestational diabetes and hypertension, and birth outcomes

Gestational Weight Gain, Body Mass Index, and Risk of Hypertensive Disorders of Pregnancy in a Predominantly Puerto Rican Population

Objectives To prospectively evaluate the association between gestational weight gain (GWG), prepregnancy body mass index (BMI), and hypertensive disorders of pregnancy using the revised Institute of Medicine (IOM) Guidelines. Methods We examined these associations among 1359 participants in Proyecto Buena Salud, a prospective cohort study conducted from 2006 to 2011 among women from the Caribbean Islands. Information on prepregnancy BMI, GWG, and incident diagnoses of hypertension in pregnancy were based on medical record abstraction. Results Four percent (n = 54) of women were diagnosed with hypertension in pregnancy, including 2.6 % (n = 36) with preeclampsia. As compared to women who gained within IOM GWG guidelines (22.8 %), those who gained above guidelines (52.5 %) had an odds ratio of 3.82 for hypertensive disorders (95 % CI 1.46-10.00; ptrend = 0.003) and an odds ratio of 2.94 for preeclampsia (95 % CI 1.00-8.71, ptrend = 0.03) after adjusting for important risk factors. Each one standard deviation (0.45 lbs/week) increase in rate of GWG was associated with a 1.74 odds of total hypertensive disorders (95 % CI 1.34-2.27) and 1.86 odds of preeclampsia (95 % CI 1.37-2.52). Conclusions for Practice Findings from this prospective study suggest that excessive GWG is associated with hypertension in pregnancy and could be a potentially modifiable risk factor in this high-risk ethnic group.

Gestational diabetes mellitus its association with obesity: a prospective cohort study

PURPOSE

The aim of this study was to investigate the association between pre-pregnancy body mass index (BMI) and gestational diabetes mellitus (GDM).

METHODS

This prospective study was conducted on 256 pregnant women without diabetes referred for prenatal care in the first trimester of pregnancy to two referral University Hospitals (Shariati and Arash Hospitals) during the years 2012 and 2013. Eligible participants were selected consecutively and were followed until delivery and 6 weeks after that. Body weight and fasting plasma glucose were measured in each trimester, and BMI was calculated. Incidence of GDM was recorded, and BMI in this group was compared with those without GDM.

RESULTS

Mean age of women was 28.70 ± 5.57 years and among them, 78 women (30.5 %) developed GDM of which 21 were obese (52.5 %), 25 overweight (27.8 %), and 32 (25.4 %) were normal weight (p = 0.004). Pre-pregnancy obesity (OR 2.74, 95 % CI 1.28-5.88, p = 0.009), family history of diabetes (OR 2.01, 95 % CI 1.13-3.56, p = 0.016), and maternal age more than 30 years (OR 2.20, 95 % CI 1.25-3.88, p = 0.006) were three independent predictors for GDM, and pre-pregnancy obesity was the most potent predictor of GDM.

CONCLUSION

Women with high BMI and obesity have a significantly higher risk for developing GDM. Pre-pregnancy obesity, family history of diabetes, and age more than 30 years are three independent risk factors for GDM.

Sociodemographic factors and pregnancy outcomes associated with prepregnancy obesity: effect modification of parity in the nationwide Epifane birth-cohort

Background

In light of the adverse outcomes for mothers and offspring related to maternal obesity, identification of subgroups of women at risk of prepregnancy obesity and its related-adverse issues is crucial for optimizing antenatal care. We aimed to identify sociodemographic factors and maternal and neonatal outcomes associated with prepregnancy obesity, and we tested the effect modification of parity on these associations.

Methods

In 2012, 3368 mothers who had delivered in 136 randomly selected maternity wards were included just after birth in the French birth cohort, Epifane. Maternal height and weight before and at the last month of pregnancy were self-reported. Maternal and neonatal outcomes were collected in medical records. Prepregnancy Body Mass Index (pBMI) was classified into underweight (<18.5), normal (18.5-24.9), overweight (25.0-29.9) and obesity (≥30.0). Since we found statistically significant interactions with parity, the multinomial logistic regression model estimating associations of pBMI class with sociodemographic characteristics and pregnancy outcomes was stratified on parity (1335 primiparous and 1814 multiparous).

Results

Before pregnancy, 7.6% of women were underweight, 64.2% were of normal weight, 18.0% were overweight and 10.2% were obese. Among the primiparous, maternal age of 25-29 years (OR = 2.09 [1.13-3.87]; vs. 30-34 years), high school level (OR = 2.22 [1.33-3.73]; vs. university level), gestational diabetes (OR = 2.80 [1.56-5.01]) and hypertensive complications (OR = 3.80 [1.83-7.89]) were independently associated with prepregnancy obesity. Among the multiparous, primary (OR = 6.30 [2.40-16.57]), junior high (OR = 2.89 [1.81-4.64]) and high school (OR = 1.86 [1.18-2.93]) education levels (vs. university level), no attendance at antenatal classes (OR = 1.77 [1.16-2.72]), excess gestational weight gain (OR = 1.82 [1.20-2.76]), gestational diabetes (OR =5.16 [3.15-8.46]), hypertensive complications (OR = 8.13 [3.97-16.64]), caesarean delivery (OR = 1.80 [1.18-2.77]) and infant birth weight ≥ 4 kg (OR = 1.70 [1.03-2.80]; vs. birth weight between 2.5 kg and 4 kg) were independently associated with prepregnancy obesity.

Conclusion

Obesity before pregnancy is associated with a set of sociodemographic characteristics and adverse pregnancy outcomes that differ across parity groups. Such findings are useful for targeted health policies aimed at attaining healthy prepregnancy weight and organizing perinatal care.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-017-1456-8) contains supplementary material, which is available to authorized users.

Determining optimal gestational weight gain in the Korean population: a retrospective cohort study

BACKGROUND

The World Health Organization (WHO) international body mass index (BMI) cut-off points defining pre-pregnancy BMI categories in the Institute of Medicine (IOM) guidelines are not directly applicable to Asians. We aimed to define the optimal gestational weight gain (GWG) for the Korean population based on Asia-specific BMI categories.

METHODS

Data from 2702 live singleton deliveries in three tertiary centers between 2010 and 2011 were analyzed retrospectively. A multivariable logistic regression analysis was conducted to determine the lowest aggregated risk of composite perinatal outcomes based on Asia-specific BMI categories. The perinatal outcomes included gestational hypertensive disorder, emergency cesarean section, and fetal size for gestational age. In each BMI category, the GWG value corresponding to the lowest aggregated risk was defined as the optimal GWG.

RESULTS

Among the study population, 440 (16.3%) were underweight (BMI < 18.5), 1459 (54.0%) were normal weight (18.5 ≤ BMI < 23), 392 (14.5%) were overweight (23 ≤ BMI < 25) and 411 (15.2%) were obese (BMI ≥ 25). The optimal GWG by Asia-specific BMI category was 20.8 kg (range, 16.7 to 24.7) for underweight, 16.6 kg (11.5 to 21.5) for normal weight, 13.1 kg (8.0 to 17.7) for overweight, and 14.4 kg (7.5 to 21.9) for obese.

CONCLUSION

Considerably higher and wider optimal GWG ranges than recommended by IOM are found in our study in order to avoid adverse perinatal outcomes. Revised IOM recommendations for GWG could be considered for Korean women according to Asian BMI categories. Further prospective studies are needed in order to determine the optimal GWG for the Korean population.

Is parity a risk factor for excessive weight gain during pregnancy and postpartum weight retention? A systematic review and meta-analysis

The aim of this study was to systematically review and meta-analyse the associations between parity, pre-pregnancy body mass index (BMI), gestational weight gain (GWG) and, when included, postpartum weight retention (PPWR). Papers reporting associations between parity and BMI and/or GWG in adult women were eligible: 2,195 papers were identified, and 41 longitudinal studies were included in the narrative synthesis; 17 studies were included in a meta-analysis. Findings indicated that parity was associated positively with pre-pregnancy BMI. In contrast, the role of parity in GWG was less clear; both positive and negative relationships were reported across studies. Parity was not associated directly with PPWR. This pattern of results was supported by our meta-analysis with the only significant association between parity and pre-pregnancy BMI. Overall, parity was associated with higher pre-pregnancy BMI; however, the role of parity in GWG and PPWR remains unclear, and it is likely that its influence is indirect and complex. Further research to better understand the contribution of parity to maternal obesity is warranted.

The effect of pre-pregnancy body mass index and excessive gestational weight gain on the risk of gestational diabetes in advanced maternal age

Background and purpose

With the popularization of a two-child policy in China, the number of pregnant women of advanced maternal age will increase steadily. We aimed to assess the association between pre-pregnancy body mass index (BMI) and weight gain in the first and second trimester and the risk of gestational diabetes (GDM) in the advanced maternal age group and control group defined as maternal age of 20–35 years.

Results

The risk of GDM for obesity before pregnancy was 2.707 (95% CI: 1.042–7.029) folds and 3.612 (95% CI: 1.182–11.039) folds in the control group and advanced maternal age group, respectively. Excessive weight gain in the first trimester was significant related to a higher risk of developing GDM with the odds ratio (OR) of 2.655 (95% CI: 1.265–5.571) and 4.170 (95% CI: 1.437–12.100) in the control group and advanced maternal age group, respectively.

Materials and methods

This prospective cohort study included 565 pregnant women with singleton pregnancy who were recruited in their first prenatal visit from the antenatal clinic in March and December 2016. Maternal weight was recorded before pregnancy, in the first prenatal visit and at the time of screening oral glucose tolerance test (OGTT). All women underwent 2 h 75g-OGTT at 24–28 weeks (24 weeks on average). GDM was diagnosed according to the standards issued by the Ministry of Health of China in 2011.

Conclusions

Elevated pre-pregnancy BMI independently increases the risk of GDM, particularly in advanced maternal age. Excessive weight gain in the first trimester is significantly associated with the incidence of GDM regardless of pre-pregnancy BMI.

Metabolic abnormalities and obesity's impact on the risk for developing preeclampsia

Preeclampsia (PE), a hypertensive disorder of pregnancy, is increasing as a major contributor to perinatal and long-term morbidity of mother and offspring. PE is thought to originate from ischemic insults in the placenta driving the release of prohypertensive anti-angiogenic [soluble fms-like tyrosine kinase-1 (sFlt-1)] and proinflammatory [tumor necrosis factor-α (TNF-α)] factors into the maternal circulation. Whereas the increased incidence of PE is hypothesized to be largely due to the obesity pandemic, the mechanisms whereby obesity increases this risk are unknown. The maternal endothelium is targeted by placental and adipose tissue-derived factors like sFlt-1 and TNF-α that promote hypertension during pregnancy, resulting in vascular dysfunction and hypertension. Interestingly, not all obese pregnant women develop PE. Data suggest that obese pregnant women with the greatest metabolic abnormalities have the highest incidence of PE. Identifying obesity-related mechanisms driving hypertension in some obese pregnant women and pathways that protect normotensive obese pregnant women, may uncover novel protocols to treat PE. Metabolic abnormalities, such as increased circulating leptin, glucose, insulin, and lipids, are likely to increase the risk for PE in obese women. It is not only important to understand whether each of these metabolic factors contribute to the increased risk for PE in obesity, but also their cumulative effects. This is particularly relevant to obese pregnant women with gestational diabetes mellitus (GDM) where all of these factors are increased and the risk for PE is highest. It is speculated that these factors potentiate the anti-angiogenic and proinflammatory mechanisms of placental ischemia-induced vascular dysfunction thereby contributing to the increasing incidence of PE.

Gestational weight gain and fetal growth in underweight women

Background

Despite the current obesity epidemic, maternal underweight remains a common occurrence with potential adverse perinatal outcomes.

Methods

We aimed to investigate the relationship between weight gain during pregnancy, and fetal growth in underweight women with low and late fertility. Women body mass index (BMI), defined according to the World Health Organization’s definition, gestational weight gain (GWG), defined by the Institute of Medicine and National Research Council and neonatal birth weight were prospectively collected at maternity ward of Policlinico Abano Terme (Italy) in 793 consecutive at term, uncomplicated deliveries.

Results

Among those, 96 (12.1 %) were categorized as underweight (BMI < 18.5 kg/m²), 551 (69.5 %) as normal weight, 107 (13.4 %) as overweight, and 39 (4.9 %) as obese, respectively. In all mother groups, GWG was within the range recommended by IOM 2009 guidelines. However, underweight women gained more weight in pregnancy (12.8 ± 3.9 kg) in comparison to normal weight (12.3 ± 6.7 kg) and overweight (11.0 ± 4.7 kg) women and their GWG was significantly higher (p < 0.001) with respect to obese women 5.8 ± 6.1 kg). In addition, offspring of underweight women were comparable in size at birth to offspring of normal weight women, whereas they were significantly lighter to offspring of both overweight and obese women.

Conclusions

Pre-pregnancy underweight does not impact birth weight of healthy, term neonates in presence of normal GWG. Presumably, medical or personal efforts to reach ‘optimal’ GWG could be a leading choice for many women living in industrialized and in low-income countries.

Pre-pregnancy body mass index, height and physical activity are associated with rate of gestational weight gain among Malaysian mothers

AIM

Both inadequate and excessive weight gain during pregnancy can have immediate and long-term health risks for women and infants. This study investigated rate of gestational weight gain (GWG) and its associated factors in Malaysian pregnant women.

METHODS

This cross-sectional study was conducted at maternal and child health clinics in Selangor and Negeri Sembilan between November 2010 and April 2012. A pre-tested questionnaire was used to obtain sociodemographic, obstetric, dietary intake and physical activity information. Current weight and height were measured using standard procedures. GWG rate was calculated as the average weekly weight gain in that particular trimester of pregnancy and further categorized according to the Institute of Medicine (IOM) recommendations.

RESULTS

Mean GWG rate for all pre-pregnancy BMI categories in the second and third trimesters was higher than the IOM recommendations. Overweight women (adjusted OR, 4.26; 95%CI: 1.92-9.44) and women <153 cm tall (adjusted OR, 1.96; 95%CI: 1.21-3.18) tend to have inadequate GWG rate. Women with high pre-pregnancy body mass index (BMI; ≥25.0 kg/m(2) ; overweight: adjusted OR, 3.88; 95%CI: 2.12-7.09; obese: adjusted OR, 2.34; 95%CI: 1.28-4.29) and low physical activity (adjusted OR, 1.74; 95%CI: 0.77-3.97) were two-threefold more likely to have excessive GWG.

CONCLUSION

Both inadequate and excessive GWG can have detrimental effects on the health of mothers and infants. Pre-pregnancy BMI, height and physical activity should be emphasized in prenatal care to ensure that women have adequate GWG rate.

Association of Pre-Pregnancy Body Mass Index and Gestational Weight Gain with Preterm Births and Fetal Size: an Observational Study from Lebanon

BACKGROUND

Pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are reported to impact the preterm birth (PTB) rate and newborn size. Most studies have been conducted in developed countries, although PTB and adverse pregnancy outcomes are more frequent in the developing world. The aim of this study is to elucidate the association of pre-pregnancy BMI and GWG on the occurrence of PTB and sub-optimal fetal size in Lebanon.

METHODS

This is a retrospective cohort study using a hospital-based register covering 35% of births in Lebanon between 2001 and 2012. Data were collected on 170 428 pregnancies from 32 hospitals using medical records and interviews.

RESULTS

After adjusting for confounders, underweight women had increased odds of having very preterm [odds ratio (OR) 1.58, 95% confidence interval (CI) 1.16, 2.14], preterm (OR 1.42, 95% CI 1.28, 1.58), and small for gestational age (SGA) (OR 1.50, 95% CI 1.37, 1.63) neonates. When BMI was analysed with GWG, only SGA remained significant in underweight women with low GWG. For all BMI groups, low GWG was protective against large for gestational age (LGA) and high GWG increased the odds of LGA. GWG, both low (OR 1.25, 95% CI 1.15, 1.35) and high (OR 1.43, 95% CI 1.32, 1.55) increased the risk of PTB in normal weight women. The same result was obtained for overweight women.

CONCLUSIONS

High GWG increased the risk of LGA for all groups and PTB in normal weight and overweight women, whereas low GWG increased the risk of SGA and PTB. Given that there are not many studies from middle income/developing countries on patterns of weight gain during pregnancy, findings from this study may help with pre-conception counselling with emphasis on the importance of an optimal pre-pregnancy BMI and appropriate weight gain during pregnancy.

A retrospective cohort study of factors relating to the longitudinal change in birth weight

BACKGROUND

Recent reports have shown a decrease in birth weight, a change from prior steady increases. Therefore we sought to describe the demographic and anthropometric changes in singleton term fetal growth.

METHODS

This was a retrospective cohort analysis of term singleton deliveries (37-42 weeks) from January 1, 1995 to January 1, 2010 at a single tertiary obstetric unit. We included all 43,217 neonates from term, singleton, non-anomalous pregnancies. Data were grouped into five 3-year intervals. Mean and median birth weight (BW), birth length (BL), and Ponderal Index (PI) were estimated by year, race and gestational age. Our primary outcome was change in BW over time. The secondary outcomes were changes in BL and PI over time.

RESULTS

Mean and median BW decreased by 72 and 70 g respectively (p < 0.0001) over the 15 year period while BL also significantly decreased by 1.0 cm (P < 0.001). This contributed to an increase in the neonatal PI by 0.11 kg/m(3) (P < 0.001). Mean gestational age at delivery decreased while maternal BMI at delivery, hypertension, diabetes, and African American race increased. Adjusting for gestational age, race, infant sex, maternal BMI, smoking, diabetes, hypertension, and parity, year of birth contributed 0.1 % to the variance (-1.7 g/year; 26 g) of BW, 1.8% (-0.06 cm/year; 0.9 cm) of BL, and 0.7% (+0.008 kg/m(3)/year; 0.12 kg/m(3)) of PI. These findings were independent of the proportional change in race or gestational age.

CONCLUSIONS

We observed a crude decrease in mean BW of 72 g and BL of 1 cm over 15 years. Furthermore, once controlling for gestational age, race, infant sex, maternal BMI, smoking, diabetes, hypertension, and parity, we identified that increasing year of birth was associated with a decrease in BW of 1.7 g/year. The significant increase in PI, despite the decrease in BW emphasizes the limitation of using birth weight alone to define changes in fetal growth.

Obesity and normal birth: A qualitative study of clinician's management of obese pregnant women during labour

BACKGROUND

Currently one-fifth of women in the UK are obese. Obese, pregnant woman are at an increased risk of experiencing complications of labour and serious morbidity. However, they are also more likely to undergo medical interventions such as induction of labour and caesarean section which in themselves confer additional health risks for obese women such as wound infection and deep vein thrombosis. Reducing unnecessary interventions and increasing normal birth rates for obese women would substantially improve their postnatal health and wellbeing and reduce the burden of NHS resources required to care for them post operatively. This research aimed to explore practitioners' experiences of and strategies for providing intrapartum care to obese women.

METHOD

A qualitative methodology was adopted, focus groups and individual interviews were conducted with health professionals. Audio recordings were transcribed verbatim and data analysed using a framework approach.

RESULTS

Twenty-four health professionals participated; Six Consultant Obstetricians two Consultant Anaesthetists and 16 midwives. Three key themes emerged from the data: medicalisation of obese birth; promotion of normal obese birth; and the complexities and contradictions in staff attitudes and behaviours. The overall interpretation is that positive approaches to obese birth offer opportunities to promote normal birth. However, many health professionals find the provision of intrapartum care to obese women challenging, and attitudes and behaviours towards the promotion of normal birth are heterogeneous, complex and contradictory.

CONCLUSION

The care of obese women during labour is generally medicalised and focussed on the associated risks. However, although there are conflicting views on how to care for obese women, some practitioners do strive to promote normality and optimise the potential for normal birth by challenging current practices and utilise some 'interventions' in order to facilitate normality and mobility during childbirth. Obesity is a major and growing health problem and a major cause of morbidity and mortality for pregnant women. It is essential that more positive proactive guidelines are available to maximise normal birth if the postnatal health of obese women is to be improved.

Joint and Independent Associations of Gestational Weight Gain and Pre-Pregnancy Body Mass Index with Outcomes of Pregnancy in Chinese Women: A Retrospective Cohort Study

Objective

To explore the joint and independent effects of gestational weight gain (GWG) and pre-pregnancy body mass index (BMI) on pregnancy outcomes in a population of Chinese Han women and to evaluate pregnant women’s adherence to the 2009 Institute of Medicine (IOM) gestational weight gain guidelines.

Methods

This was a multicenter, retrospective cohort study of 48,867 primiparous women from mainland China who had a full-term singleton birth between January 1, 2011 and December 30, 2011. The independent associations of pre-pregnancy BMI, GWG and categories of combined pre-pregnancy BMI and GWG with outcomes of interest were examined using an adjusted multivariate regression model. In addition, women with pre-pregnancy hypertension were excluded from the analysis of the relationship between GWG and delivery of small-for-gestational-age (SGA) infants, and women with gestational diabetes (GDM) were excluded from the analysis of the relationship between GWG and delivery of large-for-gestational-age (LGA) infants.

Results

Only 36.8% of the women had a weight gain that was within the recommended range; 25% and 38.2% had weight gains that were below and above the recommended range, respectively. The contribution of GWG to the risk of adverse maternal and fetal outcomes was modest. Women with excessive GWG had an increased likelihood of gestational hypertension (adjusted OR 2.55; 95% CI = 1.92–2.80), postpartum hemorrhage (adjusted OR 1.30; 95% CI = 1.17–1.45), cesarean section (adjusted OR 1.31; 95% CI = 1.18–1.36) and delivery of an LGA infant (adjusted OR 2.1; 95% CI = 1.76–2.26) compared with women with normal weight gain. Conversely, the incidence of GDM (adjusted OR 1.64; 95% CI = 1.20–1.85) and SGA infants (adjusted OR 1.51; 95% CI = 1.32–1.72) was increased in the group of women with inadequate GWG. Moreover, in the obese women, excessive GWG was associated with an apparent increased risk of delivering an LGA infant. In the women who were underweight, poor weight gain was associated with an increased likelihood of delivering an SGA infant. After excluding the mothers with GDM or gestational hypertension, the ORs for delivery of LGA and SGA infants decreased for women with high GWG and increased for women with low GWG.

Conclusions

GWG above the recommended range is common in this population and is associated with multiple unfavorable outcomes independent of pre-pregnancy BMI. Obese women may benefit from avoiding weight gain above the range recommended by the 2009 IOM. Underweight women should avoid low GWG to prevent delivering an SGA infant. Pregnant women should therefore be monitored to comply with the IOM recommendations and should have a balanced weight gain that is within a range based on their pre-pregnancy BMI.

Pre-Pregnancy BMI, Gestational Weight Gain, and the Risk of Hypertensive Disorders of Pregnancy: A Cohort Study in Wuhan, China

Background

Hypertensive disorders of pregnancy (HDP) are major causes of maternal death worldwide and the risk factors are not fully understood. Few studies have investigated the risk factors for HDP among Chinese women. A cohort study involving 84,656 women was conducted to investigate pre-pregnancy BMI, total gestational weight gain (GWG), and GWG during early pregnancy as risk factors for HDP among Chinese women.

Methods

The study was conducted between 2011–2013 in Wuhan, China, utilizing data from the Maternal and Children Healthcare Information Tracking System of Wuhan. A total of 84,656 women with a live singleton pregnancy were included. Multiple unconditional logistic regression was conducted to evaluate associations between putative risk factors and HDP.

Results

Women who were overweight or obese before pregnancy had an elevated risk of developing HDP (overweight: OR = 2.66, 95% CI = 2.32–3.05; obese: OR = 5.53, 95% CI = 4.28–7.13) compared to their normal weight counterparts. Women with total GWG above the Institute of Medicine (IOM) recommendation had an adjusted OR of 1.72 (95% CI = 1.54–1.93) for HDP compared to women who had GWG within the IOM recommendation. Women with gestational BMI gain >10 kg/m² during pregnancy had an adjusted OR of 3.35 (95% CI = 2.89–3.89) for HDP, compared to women with a gestational BMI gain <5 kg/m². The increased risk of HDP was also observed among women with higher early pregnancy (up to 18 weeks of pregnancy) GWG (>600g/wk: adjusted OR = 1.48, 95% CI = 1.19–1.84).

Conclusion

The results from this study show that maternal pre-pregnancy BMI, early GWG, and total GWG are positively associated with the risk of HDP. Weight control efforts before and during pregnancy may help to reduce the risk of HDP.

Identifying Insomnia in Early Pregnancy: Validation of the Insomnia Symptoms Questionnaire (ISQ) in Pregnant Women

STUDY OBJECTIVES

Although a substantial number of pregnant women report symptoms of insomnia, few studies have used a validated instrument to determine the prevalence in early gestation. Identification of insomnia in pregnancy is vital given the strong connection between insomnia and the incidence of depression, cardiovascular disease, or immune dysregulation. The goal of this paper is to provide additional psychometric evaluation and validation of the Insomnia Symptom Questionnaire (ISQ) and to establish prevalence rates of insomnia among a cohort of pregnant women during early gestation.

METHODS

The ISQ was evaluated in 143 pregnant women at 12 weeks gestation. The internal consistency and criterion validity of the dichotomized ISQ were compared to traditional measures of sleep from sleep diaries, actigraphy, and the Pittsburgh Sleep Quality Index using indices of sensitivity, specificity, positive and negative predictive value (PPV, NPV), and likelihood ratio (LR) tests.

RESULTS

The ISQ identified 12.6% of the sample as meeting a case definition of insomnia, consistent with established diagnostic criteria. Good reliability was established with Cronbach α = 0.86. The ISQ had high specificity (most > 85%), but sensitivity, PPV, NPV, and LRs varied according to which sleep measure was used as the validating criterion.

CONCLUSIONS

Insomnia is a health problem for many pregnant women at all stages in pregnancy. These data support the validity and reliability of the ISQ to identify insomnia in pregnant women. The ISQ is a short and cost-effective tool that can be quickly employed in large observational studies or in clinical practice where perinatal women are seen.

COMMENTARY

A commentary on this article appears in this issue on page 593.

Maternal obesity: significance on the preterm neonate

BACKGROUND

What is known of neonatal outcomes associated with maternal obesity is limited. The impact on the preterm neonate, delivery room (DR) course and need for neonatal intensive care unit (NICU) admission has not been well established.

METHODS

A review was done of our 17 county perinatal regions from the New York State Perinatal Data System database over the 3-year period of 1 January 2010-31 December 2012 for mother/baby dyad information for all live births 34-36 6/7 weeks' gestation. The National Institutes of Health body mass index (BMI) classification was used for maternal BMI with the category definitions of underweight, normal, overweight, obese Level I, obese Level II, and obese Level III.

RESULTS

Information was obtained on 2155 women. In this group, 29% had obese BMIs. The incidence of pre-pregnancy diabetes mellitus (DM), DM during gestation and cesarean delivery (CD) in obese mothers was significantly different from normal weight mothers, P<0.001. More infants of Level III mothers required DR resuscitation when compared with infants of normal BMI mothers, 36 vs 16%, P <0.001. The need for assisted ventilation beyond 6 h of age and need for NICU admission was more likely in infants of Level III mothers, P<0.001. Women in all of the obese subgroups had preterm infants with increased birth weights (BWs) compared with preterm infants of normal weight mothers, P<0.001.

DISCUSSION

Late preterm infants born to obese mothers are more likely to be delivered by cesarean section and have larger BWs. We found that infants born to obese Level III mothers are much more likely to require assisted ventilation in the DR and NICU admission.

Relationship between sociodemographics, dietary intake, and physical activity with gestational weight gain among pregnant women in Rafsanjan City, Iran

Gestational weight gain (GWG) is a determinant of health and nutrition of mothers and offspring. However, many factors associated with GWG are not completely understood. The present study assessed the relationship between sociodemographics, dietary intake, and physical activity with GWG in 308 Iranian pregnant women attending government healthcare centres in Rafsanjan city, Iran. Women gained an average of 12.87±3.57 kg during pregnancy while 54% did not gain weight within the Institute of Medicine (IOM)-recommended range. Univariate logistic models showed that gestaional weight gain was related to age, pre-pregnancy body mass index (BMI), energy intake, and sitting time. Cumulative logit model showed positive relationship between age (p=0.0137) and pre-pregnancy BMI (p<0.0001) with GWG. All pregnant women should be counselled on achieving the reccomended GWG to prevent adverse maternal and prenatal outcomes. Pre-pregnancy and gestational nutritional status and physical activity should be emphasized in antenatal care.

Excess Maternal Weight Gain and Large for Gestational Age Risk among Women with Gestational Diabetes

OBJECTIVE

To determine whether, among women with gestational diabetes (GDM), gestational weight gain above Institute of Medicine (IOM) guidelines increases the risk of large for gestational age (LGA) neonates.

STUDY DESIGN

We conducted a retrospective cohort study of singleton term pregnancies with GDM delivered at University of North Carolina Women's Hospital, Chapel Hill, NC from January 2002 to May 2010. We used Poisson regression modeling to estimate LGA risk (birth weight > 90th percentile for gestational age), by body mass index class and adherence to 2009 IOM weight gain guidelines. Women meeting IOM guidelines were the referent group. Final adjusted models included race/ethnicity, medical management of GDM, and gestational age at delivery.

RESULTS

Among the 466 women studied, mean ± standard deviation birth weight was 3,526 ± 544 g; 18% (82/466) delivered LGA neonates. Birth weight was greatest among women exceeding, compared with meeting or gaining less than, IOM guidelines (3,703 ± 545 vs. 3,490 ± 505 vs. 3,328 ± 503, p = 0.001). Exceeding IOM guideline was associated with LGA among obese women (adjusted risk ratio 2.62, 95% confidence interval 1.25, 5.50) but not among overweight or normal weight women.

CONCLUSION

Targeting gestational weight gain, a modifiable risk factor, independent of GDM treatment, may decrease LGA risk. Women with GDM may benefit from tailored weight gain recommendations.

Prepregnancy body mass index is an independent risk factor for gestational hypertension, gestational diabetes, preterm labor, and small- and large-for-gestational-age infants

OBJECTIVE

We examined if prepregnancy body mass index (BMI) is a risk factor for gestational hypertension, gestational diabetes, preterm labor, and small-for-gestational-age (SGA) and large-for-gestational-age (LGA) infants with consideration of gestational weight gain, to document the importance of preconception versus prenatal stage.

METHODS

We used the data of 219 868 women from 2004 to 2011 Pregnancy Risk Assessment Monitoring System (PRAMS). Multivariate logistic regression analyses were performed to examine the effect of prepregnancy BMI for gestational hypertension, gestational diabetes, preterm labor, and SGA and LGA infants with consideration of gestational weight gain.

RESULTS

Regardless of gestational weight gain, women with obese prepregnancy BMI (≥30 kg/m(2)) had increased odds of gestational hypertension (adjusted odds ratios (AOR) = 2.91; 95% CI = 2.76-3.07), gestational diabetes (2.78; 2.60-2.96), and LGA (1.87; 1.76-1.99) compared to women with normal prepregnancy BMI (18.5-24.9 kg/m(2)). Women with underweight prepregnancy BMI (<18.5 kg/m(2)) had increased odds of preterm labor (1.25; 1.16-1.36) and SGA infants (1.36; 1.25-1.49), but decreased odds of LGA infants (0.72; 0.61-0.85) in reference to women with normal prepregnancy BMI (18.5-24.9 kg/m(2)).

CONCLUSIONS

Regardless of adequacy of gestational weight gain, the risk of gestational hypertension, gestational diabetes, and LGA infants increases with obese prepregnancy BMI, whereas that of preterm labor and SGA infants increases with underweight prepregnancy BMI. Preconception care of reproductive aged women is as important as prenatal care to lower the risk of gestational hypertension, gestational diabetes, preterm labor, and SGA and LGA infants.

Perception of weight status and its impact on gestational weight gain in an urban population

To examine the association between actual and perceived overweight/obese status and excess gestational weight gain (GWG). As part of an infant feeding trial, multi-ethnic lower and moderate income women-completed a checklist of current health conditions, including "overweight/obesity," "asthma," and "hypertension" while pregnant. Odds of excessive GWG per the Institute of Medicine guidelines in 'accurate' versus 'inaccurate' reporters, by overweight status were analyzed with multivariate logistic regression for women with pre-or early pregnancy BMIs of ≥18.5. 775 women met study criteria. Just 21 % (n = 107) of overweight/obese women accurately identified their weight status, compared to >90 % accurate report of documented hypertension or asthma. Compared to normal-weight accurate reporters, the adjusted odds of excessive GWG in overweight/obese women was 2.3 (95 % CI 1.4, 3.7) in accurate reporters, and 2.5 (95 % CI 1.7, 3.4) in inaccurate reporters. Overweight/obesity is associated with excessive GWG, but this risk is not modified by inaccurate reporting/perception of weight-status.

Racial differences in gestational weight gain and pregnancy-related hypertension

PURPOSE

The aim of the study was to examine racial differences in gestational weight gain (GWG) and pregnancy-related hypertension.

METHODS

Logistic regression models tested racial differences in adequacy of GWG and pregnancy-induced hypertension in all singleton live births from the South Carolina 2004-2006 birth certificates.

RESULTS

Compared with white women, black and Hispanic women had 16%-46% lower odds of gaining weight above the recommendations. However, the odds of inadequate GWG was ∼50% higher in black and Hispanic women with a pregnancy body mass index (BMI) less than 25 kg/m(2). Furthermore, compared with women with adequate GWG, women with excessive GWG had higher odds of pregnancy-related hypertension (underweight: 2.35, 95% confidence interval [CI; 1.66, 3.32]; normal: 2.05, 95% CI [1.84, 2.27]; overweight: 1.93, 95% CI [1.64, 2.27]; obese: 1.46, 95% CI [1.30, 1.63]). Among women with a BMI less than 25 kg/m(2), black women had higher odds of pregnancy-related hypertension than white women (underweight: 1.64, 95% CI [1.14, 2.36]; normal weight: 1.28, 95% CI [1.15, 1.42]), whereas among women with a BMI less than 25 kg/m(2), Hispanic women had 40% lower odds.

CONCLUSIONS

Programs are needed to curb excessive GWG in all racial groups and to help some sub-groups ensure adequate GWG. Maternal obesity and GWG are two factors that should be used in combination to reduce racial differences in pregnancy-related hypertension.

Sleep disturbance and cardiometabolic risk factors in early pregnancy: a preliminary study

BACKGROUND

Cardiometabolic (CM) risk factors are linked to increased morbidity. Disturbed sleep is associated with CM risk factors in late pregnancy, but little is known about sleep in early pregnancy and CM risk factors.

METHODS

Diary and actigraphy-assessed sleep information, as well as CM outcomes (blood pressure (BP) and body mass index (BMI)), were collected thrice from pregnant women (N=161) in early pregnancy: T1 (10-12 weeks), T2 (14-16 weeks) and T3 (18-20 weeks). The sleep variables evaluated included sleep onset latency (SOL), wake after sleep onset (WASO) and total sleep time (TST). Sleep variables were dichotomised using established clinical cut-offs.

RESULTS

BMI and BP significantly changed across time. Women with persistent SOL≥20 min had greater BMI than women without persistent SOL≥20 min prior to covariate adjustment at T1 and T2, but at T3 the BMI values converged. Similar results were observed for persistent WASO≥30 min. Persistently long WASO, as measured by actigraphy, was associated with elevated SBP, after controlling for covariates.

CONCLUSIONS

Consistent with anecdotal evidence, it appears as if a subset of women report substantial difficulty initiating and maintaining sleep during early pregnancy and this may augment the risk of higher BP and BMI. Understanding these relationships is important as CM risk factors are linked to maternal and infant morbidity. Assessing sleep in early pregnancy may bestow time necessary for appropriate intervention.

Determining optimal gestational weight gain in a multiethnic Asian population

AIM

To define the optimal gestational weight gain (GWG) for the multiethnic Singaporean population.

METHODS

Data from 1529 live singleton deliveries was analyzed. A multinomial logistic regression analysis, with GWG as the predictor, was conducted to determine the lowest aggregated risk of a composite perinatal outcome, stratified by Asia-specific body mass index (BMI) categories. The composite perinatal outcome, based on a combination of delivery type (cesarean section [CS], vaginal delivery [VD]) and size for gestational age (small [SGA], appropriate [AGA], large [LGA]), had six categories: (i) VD with LGA; (ii) VD with SGA; (iii) CS with AGA; (iv) CS with SGA; (v) CS with LGA; (vi) and VD with AGA. The last was considered as the 'normal' reference category. In each BMI category, the GWG value corresponding to the lowest aggregated risk was defined as the optimal GWG, and the GWG values at which the aggregated risk did not exceed a 5% increase from the lowest aggregated risk were defined as the margins of the optimal GWG range.

RESULTS

The optimal GWG by pre-pregnancy BMI category, was 19.5 kg (range, 12.9 to 23.9) for underweight, 13.7 kg (7.7 to 18.8) for normal weight, 7.9 kg (2.6 to 14.0) for overweight and 1.8 kg (-5.0 to 7.0) for obese.

CONCLUSION

The results of this study, the first to determine optimal GWG in the multiethnic Singaporean population, concur with the Institute of Medicine (IOM) guidelines in that GWG among Asian women who are heavier prior to pregnancy, especially those who are obese, should be lower. However, the optimal GWG for underweight and obese women was outside the IOM recommended range.

The IDF Diabetes Atlas methodology for estimating global prevalence of hyperglycaemia in pregnancy

INTRODUCTION

Hyperglycaemia is one of the most prevalent metabolic disorders occurring during pregnancy. Limited data are available on the global prevalence of hyperglycaemia in pregnancy. The International Diabetes Federation (IDF) has developed a methodology for generating estimates of the prevalence of hyperglycaemia in pregnancy, including hyperglycaemia first detected in pregnancy and live births to women with known diabetes, among women of childbearing age (20-49 years).

METHODS

A systematic review of the literature for studies reporting the prevalence of gestational diabetes was conducted. Studies were evaluated and scored to favour those that were representative of a large population, conducted recently, reported age-specific estimates, and case identification was based on blood test. Age-specific prevalence data from studies were entered to produce estimates for five-year age groups using logistic regression to smooth curves, with age as the independent variable. The derived age-specific prevalence was adjusted for differences in diagnostic criteria in the underlying data. Cases of hyperglycaemia in pregnancy were derived from age-specific estimates of fertility and age-specific population estimates. Country-specific estimates were generated for countries with available data. Regional and global estimates were generated based on aggregation and extrapolation for 219 countries and territories. Available fertility rates and diabetes prevalence estimates were used to estimate the proportion of hyperglycaemia in pregnancy that may be due to total diabetes in pregnancy - pregnancy in women with known diabetes and diabetes first detected in pregnancy.

RESULTS

The literature review identified 199 studies that were eligible for characterisation and selection. After scoring and exclusion requirements, 46 studies were selected representing 34 countries. More than 50% of selected studies came from Europe and North America and Caribbean. The smallest number of identified studies came from sub-Saharan Africa. The majority of studies were for high-income countries, although low- and middle-income countries were also represented.

CONCLUSION

Prevalence estimates of hyperglycaemia in pregnancy are sensitive to the data from which they are derived. The IDF methodology is a transparent, reproducible, and modifiable method for estimating the burden of hyperglycaemia in pregnancy. More data are needed, in particular from developing countries, to strengthen the methodology.

Gestational weight gain as a risk factor for hypertensive disorders of pregnancy

OBJECTIVE

Pregnancy interventions to limit gestational weight gain (GWG) have been proposed as a means of preventing hypertensive disorders of pregnancy (HDP); however, it is currently unclear whether GWG has a causal influence on the development of HDP. Thus, we aimed to determine whether GWG in early pregnancy is a risk factor for preeclampsia and gestational hypertension and whether GWG precedes the increases in blood pressure in normotensive women across pregnancy.

STUDY DESIGN

We examined repeat antenatal clinic measurements of weight and blood pressure (median of 12 and 14 per woman, respectively) of 12,522 women in the Avon Longitudinal Study of Parents and Children.

RESULTS

Greater prepregnancy weight was associated with an increased risk of gestational hypertension and preeclampsia per 10 kg of prepregnancy weight: odds ratio (OR), 1.80; 95% confidence interval (CI), 1.70-1.91 and OR, 1.71; 95% CI, 1.49-1.95, respectively, for women weighing 90 kg or less before pregnancy; OR, 1.24; 95% CI, 1.03-1.49 and OR, 1.61; 95% CI, 1.18-2.19 for women weighing more than 90 kg. Fully adjusted odds ratios for gestational hypertension and preeclampsia per 200 g per week GWG up to 18 weeks were OR, 1.26; 95% CI, 1.16-1.38 and OR, 1.31; 95% CI, 1.07-1.62. In normotensive women, GWG in early pregnancy was associated positively with blood pressure change in midpregnancy and negatively with blood pressure change in late pregnancy. In all gestational periods, GWG was positively associated with concurrent blood pressure change. However, there was no evidence that blood pressure changes in any period were associated with subsequent GWG.

CONCLUSION

These findings suggest that GWG in early pregnancy may be a potential target for interventions aimed at reducing the risk of HDP.

Maternal pre-gravid obesity and early childhood respiratory hospitalization: a population-based case-control study

Inflammation in utero is linked to childhood respiratory and infectious complications. Obesity is an increasingly common chronic inflammatory state, yet little is known about its role in childhood respiratory illness. We sought to examine the association between maternal pre-gravid BMI and early childhood respiratory hospitalization. We conducted a population-based case-control study using the Washington State Comprehensive Hospital Abstract Reporting System and linked birth certificate data. Cases were children age 0-5 years, born in Washington state, with a respiratory hospitalization between 2003 and 2008. We identified 15,318 cases, frequency matching each case to two controls by birth year (total 31,060 controls). We used logistic regression to estimate the risk (approximated by odds ratios) of early childhood respiratory hospitalization according to maternal pre-gravid body mass index (BMI) category (underweight, normal, overweight, obese), after adjustment for maternal and infant characteristics. An elevated maternal pre-gravid BMI was associated with increased risk of childhood respiratory hospitalization, with an adjusted odds ratio OR [95 % CI] = 1.08 [1.03-1.14] for overweight mothers (BMI 25-29.9 kg/m(2)), and OR = 1.29 [1.22-1.36] for obese mothers (BMI ≥ 30 kg/m(2)). An elevated maternal pre-gravid BMI was associated with higher risk of early childhood respiratory hospitalization. Childhood respiratory illness may be an important complication of excess maternal weight that should be shared with expectant mothers.

Risk factors and outcomes of maternal obesity and excessive weight gain during pregnancy

OBJECTIVE

The prevalence of overweight and obesity among women of reproductive age is increasing. We aimed to determine risk factors and maternal, fetal and childhood consequences of maternal obesity and excessive gestational weight gain.

DESIGN AND METHODS

The study was embedded in a population-based prospective cohort study among 6959 mothers and their children. The study was based in Rotterdam, The Netherlands (2001-2005).

RESULTS

Maternal lower educational level, lower household income, multiparity, and FTO risk allel were associated with an increased risk of maternal obesity, whereas maternal European ethnicity, nulliparity, higher total energy intake, and smoking during pregnancy were associated with an increased risk of excessive gestational weight gain (all p-values <0.05). As compared to normal weight, maternal obesity was associated with increased risks of gestational hypertension (OR 6.31 (95% CI 4.30, 9.26)), preeclampsia (OR (3.61, (95% CI 2.04, 6.39)), gestational diabetes (OR 6.28 (95%CI 3.01, 13.06)), caesarean delivery (OR 1.91 (95% CI 1.46, 2.50)), delivering large size for gestational age infants (OR 2.97 (95% CI 2.16, 4.08)), and childhood obesity (OR 5.02 (95% CI:2.97, 8.45)). Weaker associations of excessive gestational weight gain with maternal, fetal and childhood outcomes were observed, with the strongest effects for first trimester weight gain.

CONCLUSIONS

Our study shows that maternal obesity and excessive weight gain during pregnancy are associated with socio-demographic, lifestyle, and genetic factors and with increased risks of adverse maternal, fetal and childhood outcomes. As compared to prepregnancy overweight and obesity, excessive gestational weight gain has a limited influence on adverse pregnancy outcomes.

Pre-pregnancy body mass index in relation to infant birth weight and offspring overweight/obesity: a systematic review and meta-analysis

BACKGROUND

Overweight/obesity in women of childbearing age is a serious public-health problem. In China, the incidence of maternal overweight/obesity has been increasing. However, there is not a meta-analysis to determine if pre-pregnancy body mass index (BMI) is related to infant birth weight (BW) and offspring overweight/obesity.

METHODS

Three electronic bibliographic databases (MEDLINE, EMBASE and CINAHL) were searched systematically from January 1970 to November 2012. The dichotomous data on pre-pregnancy overweight/obesity and BW or offspring overweight/obesity were extracted. Summary statistics (odds ratios, ORs) were used by Review Manager, version 5.1.7.

RESULTS

After screening 665 citations from three electronic databases, we included 45 studies (most of high or medium quality). Compared with normal-weight mothers, pre-pregnancy underweight increased the risk of small for gestational age (SGA) (odds ratios [OR], 1.81; 95% confidence interval [CI], 1.76-1.87); low BW (OR, 1.47; 95% CI, 1.27-1.71). Pre-pregnancy overweight/obesity increased the risk of being large for gestational age (LGA) (OR, 1.53; 95% CI, 1.44-1.63; and OR, 2.08; 95% CI; 1.95-2.23), high BW (OR, 1.53; 95% CI, 1.44-1.63; and OR, 2.00; 95% CI; 1.84-2.18), macrosomia (OR, 1.67; 95% CI, 1.42-1.97; and OR, 3.23; 95% CI, 2.39-4.37), and subsequent offspring overweight/obesity (OR, 1.95; 95% CI, 1.77-2.13; and OR, 3.06; 95% CI, 2.68-3.49), respectively. Sensitivity analyses revealed that sample size, study method, quality grade of study, source of pre-pregnancy BMI or BW had a strong impact on the association between pre-pregnancy obesity and LGA. No significant evidence of publication bias was observed.

CONCLUSIONS

Pre-pregnancy underweight increases the risk of SGA and LBW; pre-pregnancy overweight/obesity increases the risk of LGA, HBW, macrosomia, and subsequent offspring overweight/obesity. A potential effect modification by maternal age, ethnicity, gestational weight gain, as well as the role of gestational diseases should be addressed in future studies.

Pre-pregnancy body mass index moderates the effect of maternal depressive symptoms on small-for-gestational-age infants

PURPOSE

We aimed to investigate whether the negative effects of maternal depressive symptoms on Small for gestational age (SGA) was moderated by pre-pregnancy body mass index.

METHODS

A total of 9,851 women provided self-reported height and pre-pregnancy weight at their first prenatal visit. Pre-pregnancy BMI was categorized according to the BMI cut point ranges for Chinese adults. Depression during pregnancy was assessed by using standardized questionnaires. Demographic characteristics and birth outcomes, including gestational age at birth and birth weight, were collected through the interviews and case history. Multiple regression analysis was used to estimate the relationship between depressive symptoms and SGA among various pre-pregnancy BMI groups.

RESULTS

The relationship between depressive symptoms and SGA was inconsistent among three pre-pregnancy BMI groups. The incidence of SGA was positively related with depressive symptoms only among women with pre-pregnancy underweight [odds ratio (OR) 1.89, 95 % confidence interval (CI) 1.12-3.21].

CONCLUSIONS

The negative effect of depressive symptoms during pregnancy on SGA depends on pre-pregnancy BMI.

High-fat diet alters the dopamine and opioid systems: effects across development

Consumption of a high-fat diet has been linked to obesity, dyslipidemia and cardiovascular disease. Less well appreciated are adverse effects on the brain and behavior. Recent research has shown that consumption of a high-fat diet can alter gene expression within the brain, and the dopamine and opioid neurotransmitter systems appear to be vulnerable to dysregulation. This review will focus on recent reports in both humans and animal models that describe adverse effects of high-fat diet consumption on the central reward circuitry. In addition, the importance of different development windows will be discussed, with effects observed in both the prenatal/perinatal time period and with chronic high-fat diet consumption in adulthood.

From infancy to pregnancy: birth weight, body mass index, and the risk of gestational diabetes

Obesity is a risk factor for gestational diabetes, whereas the role of the mother's birth weight is more uncertain. We aimed to investigate the combined effect of mothers' birth-weight-for-gestational-age and early pregnancy Body Mass Index (BMI) in relation to risk of gestational diabetes. Between 1973 and 2006, we identified a cohort of 323,083 women included in the Swedish Medical Birth Register both as infants and as mothers. Main exposures were mothers' birth-weight-for-gestational-age (categorized into five groups according to deviation from national mean birth weight) and early pregnancy BMI (classified according to WHO). Rates of gestational diabetes increased with adult BMI, independently of birth-weight-for-gestational-age. However, compared to women with appropriate birth-weight-for-gestational-age [appropriate-for-gestational age (AGA); -1 to +1 SD] and BMI (<25.0), women with obesity class II-III (BMI ≥ 35.0) had an adjusted odds ratio (OR) of 28.7 (95 % confidence interval, CI 17.0-48.6) for gestational diabetes if they were born small-for-gestational-age [small for gestational age (SGA); <-2SD], OR = 20.3 (95 % CI 11.8-34.7) if born large-for-gestational-age [large-for-gestational-age (LGA); >2SD], and OR = 10.4 (95 % CI 8.4-13.0) if born AGA. Risk of gestational diabetes is not only increased among obese women, but also among women born SGA and LGA. Severely obese women born with a low or a high birth-weight-for-gestational-age seem more vulnerable to the development of gestational diabetes compared to normal weight women. Normal pre-pregnancy BMI diminishes the increased risk birth size may confer in terms of gestational diabetes. Therefore, the importance of keeping a healthy weight cannot be overemphasized.

Specific role of maternal weight change in the first trimester of pregnancy on birth size

The specific role of weight change in the first weeks of gestation in fetal growth has not been fully explored in humans. Our aims were to investigate: (1) the specific association between weight change in the first trimester of pregnancy (WCT1) and size at birth in term pregnancies; and (2) the role of placental weight in this relationship. From 2002 women included in the French EDEN study, 1744 mother-child pairs reached term, had pre-pregnancy weight available and at least five measures of weight in pregnancy. We extrapolated women's weight at each week of gestation with a three-degree polynomial model and estimated weight change during each trimester of gestation. We used a multivariate linear model to investigate the associations between WCT1 and birth size after taking into account potential confounders (age, parity, BMI, tobacco use, educational level, length of gestation, newborn gender, weight change after the first trimester and centre of study). Then, we performed path analysis to investigate whether the relation between WCT1 and birth size could be mediated by placental weight. After taking into account weight gain in later gestation, WCT1 was positively associated with birthweight. Results of path analysis showed that there was no direct association between WCT1 and birth size, but that this association was mediated by placental weight. Weight change during the first weeks of pregnancy may impact on fetal growth independently of weight change later in pregnancy through its effects on placental growth and function.

Excessive early gestational weight gain and risk of gestational diabetes mellitus in nulliparous women

OBJECTIVE

To estimate whether there is an association between excessive early gestational weight gain and the development of gestational diabetes mellitus (GDM) and excessive fetal growth.

METHODS

This is a secondary analysis of a randomized controlled trial of vitamins C and E in nulliparous low-risk women. Maternal weight gain from prepregnancy (self-reported) to 15-18 weeks of gestation was measured, and expected gestational weight gain was determined using the Institute of Medicine 2009 guidelines for each prepregnancy body mass index category. Excessive early gestational weight gain was defined as gestational weight gain greater than the upper range of the Institute of Medicine guidelines. Rates of GDM, birth weight greater than 4,000 g, and large for gestational age (LGA, birth weight 90 percentile or higher) were calculated and compared between women with excessive early gestational weight gain and early nonexcessive gestational weight gain (within or below Institute of Medicine guidelines).

RESULTS

A total of 7,985 women were studied. Excessive early gestational weight gain occurred in 47.5% of women. Ninety-three percent of women with excessive early gestational weight gain had total gestational weight gain greater than Institute of Medicine guidelines. In contrast, only 55% of women with nonexcessive early gestational weight gain had total gestational weight gain greater than Institute of Medicine guidelines (P<.001). Rates of GDM, LGA, and birth weight greater than 4,000 g were higher in women with excessive early gestational weight gain.

CONCLUSION

In our population, excessive early gestational weight gain occurred in 93% of women who had total gestational weight gain greater than the Institute of Medicine guidelines. In low-risk nulliparous women, excessive early gestational weight gain is associated with the development of GDM and excessive fetal growth.

LEVEL OF EVIDENCE

II.

Gestational weight gain: influences on the long-term health of the child

PURPOSE OF REVIEW

To address the recent evidence which suggests that inappropriate gestational weight gain (GWG) may have consequences that extend to the longer term health of the child.

RECENT FINDINGS

Inadequate GWG is associated with low birthweight, and excessive GWG to delivery of large for gestational age infants . Recent studies report relationships between excessive GWG and neonatal adiposity, and with childhood and adult obesity. These appear to be independent of confounders such as socioeconomic status and a shared family environment, or hereditary traits for obesity, supporting the 'developmental origins of disease' hypothesis.

SUMMARY

Because of periods of developmental plasticity, the early life metabolic environment may contribute to the risk of metabolic and cardiovascular disease in later life. The mechanisms which explain the relationships between maternal GWG and later life obesity remain unknown. Large, well conducted, intervention randomized controlled trials in pregnant women are required to address relationships between GWG and offspring risk of disease, including characterization of potential mediators. These should lead to more targeted and effective intervention strategies.

Maternal anthropometric measurements and other factors: relation with birth weight of neonates

The objective of this study was to examine the influence of anthropometric measurements of pregnant women, gestational weight gain, fundal height, and maternal factors, namely age, education, family income, parity along with maternal hemoglobin, on birth weight of neonates. A cross sectional study was performed in Khoy City in north west of Iran. Four hundred and fifty healthy pregnant women in the age between 16-40 years were selected for this study from seven health urban centers and one referral hospital. Findings showed that the mean age, height, fundal height, maternal weight, and gestational weight gain during pregnancy were 26.1 years, 159.1 cm, 32.9 cm, 72.0 kg, 11.8 kg respectively. The mean birth weight of neonates was 3.2 kg and 11% of neonates showed low birth weight. Age, family income, maternal height, weight, gestational weight gain and fundal height were significantly associated with birth weight of neonates. Using binary logistic regression analysis, fundal height, maternal hemoglobin, family income and gestational weight gain of pregnant women could be considered as predictive factors of birth weight of neonates.

Dynamic energy-balance model predicting gestational weight gain

BACKGROUND

Gestational weight gains (GWGs) that exceed the 2009 Institute of Medicine recommended ranges increase risk of long-term postpartum weight retention; conversely, GWGs within the recommended ranges are more likely to result in positive maternal and fetal outcomes. Despite this evidence, recent epidemiologic studies have shown that the majority of pregnant women gain outside the target GWG ranges. A mathematical model that predicts GWG and energy intake could provide a clinical tool for setting precise goals during early pregnancy and continuous objective feedback throughout pregnancy.

OBJECTIVE

The purpose of this study was to develop and validate a differential equation model for energy balance during pregnancy that predicts GWG that results from changes in energy intakes.

DESIGN

A set of prepregnancy BMI-dependent mathematical models that predict GWG were developed by using data from a longitudinal study that measured gestational-changes in fat-free mass, fat mass, total body water, and total energy expenditure in 63 subjects.

RESULTS

Mathematical models developed for women with low, normal, and high prepregnancy BMI were shown to fit the original data. In 2 independent studies used for validation, model predictions of fat-free mass, fat mass, and total body water matched actual measurements within 1 kg.

CONCLUSIONS

Our energy-balance model provides plausible predictions of GWG that results from changes in energy intakes. Because the model was implemented as a Web-based applet, it can be widely used by pregnant women and their health care providers.