The Protective Effect of Exclusive Breastfeeding on Overweight/Obesity in Children with High Birth Weight.

BACKGROUND: A positive association between birth weight (BW) and body mass index (BMI) has been shown among children in many populations. The aim of this study was to investigate BMI trajectory according to BW status and the protective effect of breastfeeding on the prevalence of overweight/obesity in children 6 years of age. METHODS: A retrospective cohort study was conducted between January 1, 2008 and December 31, 2016 utilizing data from the National Health Information Database of Korea. The 38,049 subjects were followed until the end of 2016, providing that subjects were completely eligible for all health check-ups from birth to 6 years of age. At each check-up period, multiple logistic regressions were used to investigate the association between BW status (low birth weight [LBW], normal birth weight [NBW], high birth weight [HBW]) and growth development. RESULTS: HBW infants were highly likely to be overweight/obese compared to NBW infants (odds ratio [OR], 1.70-2.35) and LBW infants were highly likely to be underweight (OR, 1.69-2.20) through 6 years of age. The risk of overweight/obesity decreased significantly if HBW infants were breast-fed for 6 months (OR, 0.54-0.76). CONCLUSION: HBW status is associated with overweight/obesity during early childhood. Exclusive breastfeeding is a significant protective factor against overweight/obesity in children with HBW.

Greater Breastfeeding in Early Infancy Is Associated with Slower Weight Gain among High Birth Weight Infants.

OBJECTIVE: To examine whether feeding patterns from birth to age 6 months modify the association between birth weight and weight at 7-12 months of age. STUDY DESIGN: Longitudinal mixed models were used to examine feeding trajectories across categories of birth weight and weight at 7-12 months of age in 1799 mother-infant dyads enrolled in the Infant Feeding Practices Study II. The percentage of breast milk received and the average daily formula consumption were calculated from birth to 6 months of age. Birth weights were classified as high (≥4000 g) and normal (≥2500 g and <4000 g). Weights at 7-12 months of age were categorized as high (z score >1) or normal (z score ≤1). A secondary analysis was performed using categories defined by birth weight adjusted for gestational age percentiles (>90% and 10th-90th percentile). RESULTS: High birth weight (HBW) infants with high weights at 7-12 months of age demonstrated a rapid decline in the percentage of breast milk feedings compared with HBW infants with normal weights at 7-12 months of age. Normal birth weight infants with high weights at 7-12 months of age received a lower percentage of breast milk and had greater absolute intakes of formula than those with normal weights at 7-12 months of age; these associations did not vary over time. Results were similar when infants were categorized by birth weight percentiles. CONCLUSIONS: A lower proportion of breast milk feedings was associated with excess weight at 7-12 months of age in HBW infants. These findings suggest an initial target for obesity prevention programs focusing on the first 6 months after birth.

Associations between high birth weight, being large for gestational age, and high blood pressure among adolescents: a cross-sectional study.

PURPOSE: Low birth weight and being small for gestational age are associated with increased risk of cardiometabolic diseases. However, the results from the studies examining the associations between high birth weight (HBW), being large for gestational age (LGA), and high blood pressure (HBP) are inconsistent. The aim of this study was to evaluate the associations between HBW and being LGA alone and in combinations with body mass index (BMI) categories in adolescence and HBP among Lithuanian adolescents aged 12-15 years. METHODS: The participants with HBP (≥90th percentile) were screened on two separate occasions. Data on the BMI, birth weight (BW), gestational age, and BP were analyzed in 4598 adolescents. Adjusted odds ratios (aORs) with 95% confidence intervals (CI) for the associations were estimated using multivariate logistic regression models. RESULTS: The overall prevalence of HBW (>4000 g), being LGA, adolescent overweight/obesity, and HBP were 13.9, 10.4, 14.5, and 25.6%, respectively. After adjustment for age, sex, and BMI, significant positive associations were found between HBW and being LGA and HBP (HBW: aOR 1.34; 95% CI, 1.11-1.63; LGA: aOR 1.44; 95% CI, 1.16-1.79). After adjustment for age and sex and compared to BW 2500-4000 g and being AGA (appropriate for gestational age) with normal weight in adolescence, the combinations that included both risk factors-HBW with overweight/obesity and being LGA with overweight/obesity-showed higher aORs (aOR 4.36; 95% CI, 3.04-6.26; and aOR 5.03; 95% CI, 3.33-7.60, respectively) than those with either of these risk factors alone did. CONCLUSIONS: HBW and being LGA were positively associated with HBP in Lithuanian adolescents aged 12-15 years. The highest odds of having HBP were observed for subjects with both risk factors-neonatal HBW or being LGA and overweight/obesity in adolescence.

High birth weight was associated with increased radial artery intima thickness but not with other investigated cardiovascular risk factors in adulthood.

AIM: This study investigated whether a high birth weight was associated with increased risk factors for cardiovascular disease when Swedish adults reached 34-40. METHODS: We studied 27 subjects born at Uppsala University Hospital in 1975-1979, weighing at least 4500 g, and compared them with 27 controls selected by the Swedish National Board of Welfare with birth weights within ±1 standard deviations scores and similar ages and gender. The study included body mass index (BMI), blood pressure, lipid profile, haemoglobin A1c (HbA1c), C-reactive protein (CRP) and high-frequency ultrasound measurements of intima-media thickness, intima thickness (IT) and intima:media ratio of the carotid and radial arteries. RESULTS: Subjects with a high birth weight did not differ from controls with regard to BMI, blood pressure, lipid profile, high-sensitivity CRP, HbA1c or carotid artery wall dimensions. However, their radial artery intima thickness was 37% greater than the control group and their intima:media ratio was 44% higher. CONCLUSION: Our findings indicate that a high birth weight was associated with increased radial artery intima thickness, but not with other investigated cardiovascular risk factors, at 34-40 years of age. The clinical implications of these findings should be investigated further, especially in subjects born with a very high birth weight.

Comparison of High and Normal Birth Weight Infants on Eating, Feeding Practices, and Subsequent Weight.

Objectives High birth weight (HBW ≥ 4000 g) infants are at increased risk for obesity, but research has yet to identify the mechanism for this increased risk and whether certain subsets of HBW infants are at greater risk. Methods This exploratory study examined child eating behaviors and maternal feeding practices and beliefs across 21 HBW and 20 normal birth weight (NBW, 2500-3999 g) infants at 7-8 months of age using maternal-report measures (n = 41) and a bottle feeding task (n = 16). Results HBW infants were at increased risk for high weight-for-length at 7-8 months (F (2, 38) = 6.03, p = .02) compared to NBW infants, but no statistically significance differences on weight gained per day since birth, child eating behaviors, or most maternal feeding practices and beliefs were found between HBW and NBW infants. However, HBW infants who maintained a high weight-for-length (≥ 85th percentile) at 7-8 months had a higher birth weight, gained more weight per day, and had lower maternal-reported satiety responsiveness and maternal social interactions during feedings than their HBW counterparts who were currently below the 85th percentile. Conclusions for Practice HBW infants did not differ from NBW infants on eating behaviors and feeding practices, but children born at HBW who maintain excess weight during infancy do differ from those infants who fall below the 85th percentile for weight-for-length. Future research should identify risk factors that longitudinally differentiate HBW infants at greatest risk for maintaining excess weight and develop early screening and intervention efforts for this subset of at-risk infants.

General Movements Assessment in Infants with High Birth Weight.

BACKGROUND: High birth weight (HBW) describes fetal birth weight of more than 4000 g. Infants with HBW have a high risk of developing neurological and developmental problems. Until recently, there were no studies in the literature that investigated the quality of spontaneous movements and the integrity of the developing nervous system in infants with HBW. The aims of this study were (1) to describe age-specific detailed early spontaneous movements in infants with HBW and (2) to compare the detailed early spontaneous movements of infants with HBW and normal birth weight (NBW). METHODS: Twenty-two infants with HBW (median birth weight = 4190 g) and 22 infants with NBW (median birth weight = 3255 g) were included at 10 to 19 weeks post-term age (median = 13 weeks). All infants were assessed according to General Movement Assessment using three- to five-minute video recordings. Video recordings of each infant were evaluated using Motor Optimality Score for three- to five-month-old infants-Revised score sheet. RESULTS: Motor Optimality Score-Revised (MOS-R) (P < 0.001), observed postural patterns (P < 0.001), and age-adequate movement repertoire (P = 0.005) were significantly lower in the infants with HBW. Infants with HBW had more aberrant (abnormal or absent) fidgety movements (18%) than those with NBW (0%). CONCLUSIONS: The results of this study demonstrated that the motor repertoire of infants with HBW tended to decrease more than that of those with NBW. To enable the follow-up of progression as a result of these assessments infants in need should be referred to age-adequate early intervention programs.

Association of trajectories and cumulative exposure of antenatal depression with high birth weight.

BACKGROUND: Inconsistent associations between antenatal depression and fetal birth weight were reported previously, and little is known about the dynamic changes and long-term cumulative effect of antenatal depression during pregnancy. METHODS: Participants were from the Tongji-Huaxi-Shuangliu Birth Cohort. Depressive symptoms were measured using the Edinburgh Postnatal Depression Scale in early, middle, and late pregnancy respectively. Trajectories of antenatal depression were assessed using the latent class mixed model. The percentage of days with depression (PDD) and frequency of antenatal depression were measured to assess the cumulative exposure. Multivariable logistic regression models were used to evaluate the associations of antenatal depression with macrosomia and large for gestational age (LGA). RESULTS: We identified four distinct trajectories, including the low stable group (n = 1,327, 27.99 %), the moderate stable group (n = 2,610, 55.05 %), the peak group (n = 407, 8.58 %), and the valley group (n = 397, 8.37 %). Compared with the low stable group, the valley group showed a higher risk of macrosomia (OR, 1.98; 95 % CI, 1.17, 3.38) and LGA (OR, 1.44; 95 % CI, 1.002, 2.09); the peak group showed a higher risk of LGA (OR, 1.52; 95 % CI, 1.07, 2.16), but the association was not significant for macrosomia (OR, 1.47; 95 % CI, 0.85, 2.55). Consistently, cumulative antenatal depression was also positively associated with the risks of macrosomia and LGA. LIMITATION: The antenatal depression was self-reported using a screening scale and information bias could not be ruled out. CONCLUSION: Certain trajectories and cumulative exposure of antenatal depression were associated with higher risks of high birth weight.

Birth Weight and Subsequent Risk of Total Leukemia and Acute Leukemia: A Systematic Review and Meta-Analysis.

Objective: Birth weight, an important indicator of fetal nutrition and degree of development, may affect the risk of subsequent leukemia. At present, little is known about the effect of birth weight on acute myeloid leukemia (AML) and whether there is a dose-dependent relationship of birth weight with acute lymphoid leukemia (ALL) and AML. To address these questions, the present work aimed to systematically investigate the relationship between birth weight and the risk of subsequent leukemia based on the current epidemiological studies Methods: Relevant studies were systematically retrieved from electronic databases PubMed, Embase, and Cochrane Library, from inception to May 15th, 2021. Finally, 28 studies (including 21 case-control studies and 7 cohort studies) were included for the final meta-analysis. Results in cohort studies were performed by risk ratios (RRs), while those in case-control studies by odds ratios (ORs), and all results were assessed by adopting the random-effect model. Besides, a dose-dependent analysis was conducted based on the cohort studies. Results: Compared with the population with normal birth weight (NBW), the population with high birth weight (HBW) might have an increased risk of leukemia (OR 1.33, 95%CI 1.20-1.49; I 2 0%). Meanwhile, low birth weight (LBW) was associated with a decreased risk of ALL, as evidenced from the pooled analysis of case-control studies (OR 0.83, 95% CI 0.75-0.92; I 2 23.3%). However, relative to NBW population, the HBW population might have an increased risk of ALL (OR 1.28, 95% CI 1.20-1.35; I 2 7%). There was no obvious evidence supporting the relationship between LBW and the risk of AML from the pooled analysis of case-control studies (OR, 1.11 95% CI 0.87-1.42; I 2 31.7%). Conclusions: Overall, in children and young adults, HBW population may be associated with the risks of subsequent leukemia and AML relative to NBW population, but the supporting dose-dependent evidence is lacking. In addition, compared with NBW population, there is stronger evidence supporting a significantly increased risk of subsequent ALL in HBW population, and a decreased risk in LBW population in a dose-dependent manner. More prospective studies with large samples are warranted in the future to validate and complement these findings.

Low and high birth weight in a hospital population in Sudan: An analysis of clinical cut-off values.

OBJECTIVE: To determine the cut-off values for low birth weight (LBW) and high birth weight (HBW) of Sudanese newborns. METHODS: Data (maternal age, parity, birth weight, and gender of the newborn) from women (n = 2818) who delivered at Saad Abualila Hospital in Khartoum were retrieved from the medical files. RESULTS: The cut-off for LBW (the 10th centile) was 2400 g and the 90th centile (HBW) was 3700 g. Out of 2818 newborns, 317 (11.2%) had birth weights below 2400 g. Using the WHO (traditional) cut-off of 2500 g, the prevalence of LBW was 14.3%. The difference between the two prevalences of LBW was statistically significant (P < 0.001). However, the agreement rate between the two was high (κ = 0.86). The cut-off to define HBW was 3700 g. In the study, 292 (10.4%) newborns had birth weights of at least 3700 g. Using the cut-off of 4000 g, the prevalence of HBW was 9.5%. The difference between the two prevalences of HBW was statistically significant (P < 0.001). However, the agreement rate between the two was low (κ = 0.06). CONCLUSION: The cut-off values for low and high birth weight were 2400 and 3700 g, respectively.

Is there a relationship between high birth weight and umbilical vein diameter?

OBJECTIVE: The aim of the study was to evaluate the associations between sonographical measurements of the umbilical cord and birth weight in 20-24 weeks of gestations. METHODS: This cross-sectional study was conducted with the participation of 220 low-risk pregnant women between 20-24 gestational weeks. Biparietal diameter, head and abdominal circumference, and femur length were measured for anthropometric calculations. Umbilical cord including umbilical vein diameters, placental thickness, umbilical artery. Doppler measurements (RI, PI) were recorded. RESULTS: In accordance with the results of statistical computations, an inverse relationship was found between umbilical vein diameter and birth weight of a large gestational age (LGA) newborn in 20-24 gestational weeks (p < .05). There was no significant relationship between other parameters and birth weight of LGA newborns. CONCLUSION: There is an inverse relationship between birth weights of newborns with LGA and umbilical vein diamater at 20-24 weeks of pregnancy. The umbilical vein diameter in the second trimester may be a promising measurement on predicting LGA fetus. The researches have not confirmed the physiopathology of this finding yet, but it is paving the path for future studies.

The Association Between High Birth Weight and Long-Term Outcomes-Implications for Assisted Reproductive Technologies: A Systematic Review and Meta-Analysis.

Background: Studies have shown that the prevalence of children born with high birth weight or large for gestational age (LGA) is increasing. This is true for spontaneous pregnancies; however, children born after frozen embryo transfer (FET) as part of assisted reproductive technology (ART) also have an elevated risk. In recent years, the practice of FET has increased rapidly and while the perinatal and obstetric risks are well-studied, less is known about the long-term health consequences. Objective: The aim of this systematic review was to describe the association between high birth weight and LGA on long-term child outcomes. Data Sources: PubMed, Scopus, and Web of Science were searched up to January 2021. Exposure included high birth weight and LGA. Long-term outcome variables included malignancies, psychiatric disorders, cardiovascular disease, and diabetes. Study Selection: Original studies published in English or Scandinavian languages were included. Studies with a control group were included while studies published as abstracts and case reports were excluded. Data Extraction: The methodological quality, in terms of risk of bias, was assessed by pairs of reviewers. Robins-I (www.methods.cochrane.org) was used for risk of bias assessment in original articles. For systematic reviews, AMSTAR (www.amstar.ca) was used. For certainty of evidence, we used the GRADE system. The systematic review followed PRISMA guidelines. When possible, meta-analyses were performed. Results: The search included 11,767 articles out of which 173 met the inclusion criteria and were included in the qualitative analysis, while 63 were included in quantitative synthesis (meta-analyses). High birth weight and/or LGA was associated with low to moderately elevated risks for certain malignancies in childhood, breast cancer, several psychiatric disorders, hypertension in childhood, and type 1 and 2 diabetes. Conclusions: Although the increased risks for adverse outcome in offspring associated with high birth weight and LGA represent serious health effects in childhood and in adulthood, the size of these effects seems moderate. The identified risk association should, however, be taken into account in decisions concerning fresh and frozen ART cycles and is of general importance in view of the increasing prevalence in high birthweight babies.

High birth weight and its interaction with physical activity influence the risk of obesity in early school-aged children.

BACKGROUND: High birth weight (HBW) is associated with childhood obesity, but with inconsistent results. This study investigated the relationship between HBW and childhood obesity, and further explored the interaction of HBW with behavioral and socio-economic determinants of obesity. METHODS: This cross-sectional study enrolled 1906 grade-two children of Guangzhou, China, from June to November, 2016. Overweight/obesity corresponded to a body mass index higher than the sex-age-specific criteria. Abdominal obesity was assessed using the sex-specific waist-height ratio cutoffs. The association of HBW with obesity was evaluated in multivariable logistic regression model. The relative excess risk due to interaction (RERI) and the attributable proportion of interaction (AP) indices were used to measure additive interaction, while applying the interaction of OR index for multiplicative interaction assessment. RESULTS: Children with HBW had an increased risk of overweight/obesity [odds ratio (OR) = 2.42, 95% confidence interval (CI) = 1.56-3.76] compared with those without HBW. Significant additive interaction of HBW with physical activity was found for overweight/obesity [relative excess risk due to interaction (RERI) = 2.69, 95% CI = 0.62-4.75; attributable proportion of interaction (AP) = 0.72, 95% CI = 0.42-1.02]. The HBW children with insufficient activity had higher odds of overweight/obesity compared to the non-HBW children with sufficient activity (OR = 3.75, 95% CI = 2.06-6.83). In addition, we identified a significant interaction of HBW with household income for abdominal obesity (RERI = 1.20, 95% CI = 0.02-2.37; AP = 0.76, 95% CI = 0.16-1.36). CONCLUSIONS: HBW confers an increased risk for childhood overweight/obesity. Physical activity attenuates the effect of HBW on overweight/obesity, and HBW possibly synergistically interacts with high household income to promote abdominal obesity in childhood.

Birth Weight and Incidence of Breast Cancer: Dose-Response Meta-analysis of Prospective Studies.

BACKGROUND: Many studies have shown the association between birth weight and breast cancer (BC), but the evidence remains limited and inconsistent, especially in different menopause status. We sought to clarify the relationship and shape of the dose-response relation between birth weight and BC. METHODS: The Web of Science, PubMed, and Embase databases were searched for prospective studies involving the relationship between birth weight and risk of BC published to November 2019. Random effects of generalized least squares regression models were used to estimate the quantitative dose-response association, and restricted cubic splines were used to model the association. RESULTS: We included reports of 16 prospective studies describing 16,000 incident cases among 553,644 participants. We identified a modest-in-magnitude, but significant, association between birth weight and BC risk: risk increased by 2% (risk ratio, 1.02, 95% confidence interval, 1.01-1.03) and 9% (risk ratio, 1.09, 95% confidence interval, 1.04-1.15) with a per-500 g birth weight increment in all ages and premenopausal women, respectively. Our results showed a linear dose-response relationship between birth weight and BC risk (Pnonlinearity = .311) in premenopausal women, with statistical significance when birth weight was above about 3.5 kg. No significant association was found in postmenopausal women. CONCLUSION: Higher birth weight has a relationship with increased risk of BC in premenopausal women, particularly when birth weight is above 3.5 kg.

Early-life determinants of excess weight in children born heavy.

Infants born heavy are vulnerable to later obesity, but it is unknown whether obesity-related risk factors present between conception and delivery predict their postnatal weight trajectory. We modelled the weight trajectories of infants born high birth weight (HBW, greater than or equal to 4000 g) and/or large for gestational age (LGA, greater than 90th percentile) using data from the Infant Feeding Practices Study II (N = 371). A high percentage of infants were both HBW and LGA, but the trajectories were modelled separately. Weight of infants born heavy begins high, gradually decreases, and then levels off by 12 months. Delivery method was the only predictor of weight. Caesarean-delivered HBW infants were heavier than vaginally-delivered HBW infants although this effect disappeared by 12 months. Findings indicate that early-life influences are not necessarily deterministic of the postnatal weight trajectory of infants born heavy. Future research is needed to examine postnatal behaviours that may be implicated in the relationship between large size at birth and later obesity.

Association of high birth weight with overweight and obesity in Chinese students aged 6-18 years: a national, cross-sectional study in China.

BACKGROUND: The prevalence of childhood overweight and obesity in China has drastically increased 57 times over the past 30 years, and to control birth weight is an effective way to reduce the risk of overweight and obesity across the life course. OBJECTIVE: This paper aimed to evaluate the association of high birth weight (HBW) with overweight and obesity in Chinese students aged 6-18 years. METHODS: All students with HBW (n=4981) aged 6-18 years were selected from a cross-sectional survey from seven provinces of China, and 4981 other students with normal birth weight (NBW) were randomly sampled with matched gender, age and province. Anthropometric parameters were measured and characteristics were collected by questionnaires. Multiple logistic regression was used to estimate the OR of overweight and obesity with HBW, unadjusted and adjusted for confounding factors. RESULTS: Participants with HBW revealed higher body mass index in childhood. The prevalence of overweight and obesity was significantly higher in the HBW group than in the NBW group (overweight 15.3% vs 13.1%, p<0.05; obesity 16.9% vs 10.6%, p<0.05), and the results were similar for overweight in all age groups except age 6-7, age 14-15 and age 16-18. Additionally, HBW was positively associated with overweight (OR=1.230; 95% CI 1.056 to 1.432) and obesity (OR=1.611; 95% CI 1.368 to 1.897) after adjustment for covariates. CONCLUSIONS: HBW leads to an increased risk of overweight and obesity in childhood; thus, measures to control birth weight, such as controlling gestational weight gain, should be taken from the earliest beginning of life. TRIAL REGISTRATION NUMBER: NCT02343588; Post-results.

The hefty fetal phenotype hypothesis revisited: high birth weight, type 2 diabetes and gestational diabetes in a Saskatchewan cohort of First Nations and non-First Nations women.

Although low birth weight (LBW) increases the risk for type 2 diabetes (T2DM), the relationship between high birth weight (HBW) and T2DM is less definitive and largely confined to North American Indigenous populations. We re-examined the relationship between LBW (4000 g) and both T2DM and gestational diabetes (GDM) among First Nations and non-First Nations women in Saskatchewan. We analyzed new data for female subjects from a 2001 case-control study that led to our hefty fetal phenotype hypothesis. Using survival analysis techniques and a validated algorithm for identifying diabetes in health care administrative data, we followed a 1950-1984 birth cohort of 2003 women until March 31, 2013. Cox regression analysis determined the time to occurrence of first episode of GDM and diagnosis of T2DM by birth weight and ethnicity. First Nations women with HBW demonstrated a greater risk for developing both T2DM [hazard ratios (HR) 1.568; 95% confidence interval (CI) 1.188, 2.069] and GDM (HR 1.468; 95% CI 1.016, 2.121) than those with normal birth weight (NBW). Non-First Nations women with LBW had a greater risk of developing GDM than those with NBW (HR 1.585; 95% CI 1.001, 2.512). HBW is a risk factor for GDM and T2DM among First Nations women. This is likely due to exposure of these women to their own mothers' diabetic pregnancies or gestational impaired glucose tolerance. This inter-generational amplification of T2DM risk mediated through prenatal exposures appears to play a substantial role in the epidemic of T2DM among First Nations peoples.

The relationship between maternal weight gain in pregnancy and newborn weight.

AIM: This study investigated the impacts of different pre-pregnancy body mass indexes and gestational weight gain on the risk of delivering a high birth weight infant in China. METHODS: A retrospective cohort study was conducted from 2013 to 2014 in the Maternal and Child Health Care Hospital of Jinan City, Shandong Province and 2415 women who had a singleton birth were included in the study. A logistic regression model and restricted cubic spline regression were used to analyse the association. FINDINGS: The risk of delivering a high birth weight infant increases when the mother's pre-pregnancy body mass index exceeds 24kg/m2. Compared with women whose pre-pregnancy body mass index was 21kg/m2, the adjusted risk of delivering a high birth weight infant doubled when the mother's pre-pregnancy body mass index was 29kg/m2, and nearly tripled when the mother's pre-pregnancy body mass index was 31kg/m2. Compared with women who had a gestational weight gain of 12.0kg, women having a gestational weight gain of 20.0kg, 22.0kg, and 26.0kg had a 1.7-, 2.2-, and 3.5-fold increased risk of delivering a high birth weight infant. When the mother experiences a gestational weight gain greater than 27kg, the risk of delivering a high birth weight infant is at least 4-fold greater than that for a mother who has a gestational weight gain of 12.0kg. CONCLUSIONS: Proposed strategies to raise public awareness of the risks to infants posed by high maternal pre-pregnancy body mass index and gestational weight gain are required. All clinical recommendations and measures are for all pregnant women, not just overweight and obese pregnant women.

Associations between maternal anthropometric characteristics and infant birth weight in Iranian population.

OBJECTIVE: To examine the (1) normal ranges of anthropometric and insulin resistance/sensitivity indices (homeostatic model assessment for insulin resistance, homeostatic model assessment for insulin sensitivity, and quantitative insulin sensitivity check index) for Iranian pregnant women and their newborns and (2) associations between maternal anthropometric and metabolic values and infants' birth weights among Iranian women. METHODS: Anthropometric and metabolic values of 163 singleton non-diabetic pregnant women in Tehran, Iran (2014) were collected before and during pregnancy and at delivery. Linear regression, multivariable regression, and Student t tests were used to evaluate correlations between birth weight and maternal variables. RESULTS: Linear regression modeling suggested that maternal serum glucose (p = 0.2777) and age (p = 0.6752) were not associated with birth weight. Meanwhile, maternal weight and body mass index before pregnancy (p = 0.0006 and 0.0204, respectively), weight at delivery (p = 0.0036), maternal height (p = 0.0118), and gestational age (p = 0.0016) were positively associated with birth weight, while serum insulin (p = 0.0300) and homeostatic model assessment for insulin resistance (p = 0.0334) were negatively associated with infant's birth weight. Using multivariate modeling, we identified severalconfounders: parity (multipara mothers delivered heavier babies compared to first-time mothers) explained as much as 24% of variation in birth weight (p = 0.005), maternal height explained 20.7% (p = 0.014), gestational age accounted for 19.7% (p = 0.027), and maternal body mass index explained 19.1% (p = 0.023) of the variation in the infant's birth weight. Maternal serum insulin and infant's sex were not observed to be associated with birth weight (p = 0.342 and 0.669, respectively) in the overall model. CONCLUSION: Overweight/obese women may experience higher incidence of delivering larger babies. Multivariable regression analyses showed that maternal body mass index and height, parity, and gestational age are associated with newborn's birth weight.

Maternal pre-pregnancy BMI, gestational weight gain, and infant birth weight: A within-family analysis in the United States.

In the United States, the high prevalence of unhealthy preconception body weight and inappropriate gestational weight gain among pregnant women is an important public health concern. However, the relationship among pre-pregnancy BMI, gestational weight gain, and newborn birth weight has not been well established. This study uses a very large dataset of sibling births and a within-family design to thoroughly address this issue. The baseline analysis controlling for mother fixed effects indicates maternal preconception overweight, preconception obesity, and excessive gestational weight gain significantly increase the risk of having a high birth weight baby, respectively, by 1.3, 3 and 3.9 percentage points, while underweight before pregnancy and inadequate gestational weight gain increase the low birth weight incidence by 1.4 and 2 percentage points. The benchmark results are robust in a variety of sensitivity checks. Since poor birth outcomes especially high birth weight and low birth weight have lasting adverse impacts on one's health, education, and socio-economic outcomes later in life, the findings of this research suggest promoting healthy weight among women before pregnancy and preventing inappropriate weight gain during pregnancy can generate significant intergenerational benefits.

A high birth weight is associated with increased risk of type 2 diabetes and obesity.

BACKGROUND: The association between low birth weight and adult disease is well known. Less is known on long-term effects of high birth weight. OBJECTIVE: This study aims to investigate whether a high birth weight increases risk for adult metabolic disease. METHODS: Swedish term single births, 1973-1982 (n = 759,999), were studied to age 27.5-37.5 years using Swedish national registers. Hazard ratios (HRs) were calculated in relation to birth weight for type 2 diabetes, obesity, hypertension and dyslipidaemia. RESULTS: Men with birth weights between 2 and 3 standard deviation score (SDS) had a 1.9-fold increased risk (HR 1.91, 95% confidence interval [CI] 1.25-2.90) of type 2 diabetes, whereas those with birth weights above 3 SDS had a 5.4-fold increased risk (HR 5.44, 95% CI 2.70-10.96) compared to men with birth weights between -2 and 2 SDS. The corresponding HRs for women were 0.60 (95% CI 0.40-0.91) and 1.71 (95% CI 0.85-3.43) for birth weights 2-3 SDS and >3 SDS, respectively. Men with birth weights between 2 and 3 SDS had a 1.5-fold increased risk (HR 1.47, 95% CI 1.22-1.77) of obesity. The corresponding risk for women was 1.3-fold increased (HR 1.32, 95% CI 1.19-1.46). For men and women with birth weights above 3 SDS, the risks of adult obesity were higher, HR 2.46 (95% CI 1.63-3.71) and HR 1.85 (95% CI 1.44-2.37), respectively. CONCLUSIONS: A high birth weight, particularly very high, increases the risk of type 2 diabetes in male young adults. The risk of obesity increases with increasing birth weight in both genders.