INTERGROWTH-21st Standards Research Articles

Predictors of inadequate gestational weight gain according to iom recommendations and intergrowth-21st standards: the araraquara cohort study

BackgroundGestational weight gain (GWG) is a critical factor for maternal and fetal health.ObjectiveTo identify maternal predictors of inadequate GWG according to the 2009 Institute of Medicine (IOM) recommendations and Intergrowth-21st standards.MethodsA prospective epidemiological cohort study conducted from 2017 to 2023 in southeastern Brazil assessed 1,557 women at three different stages of pregnancy (≤ 18, 20–26, and 30–36 weeks of gestation) and at delivery. Sociodemographic, obstetric, lifestyle, nutritional, and maternal morbidity characteristics were collected, along with biochemical parameters.ResultsAmong the participants, 38.7% had GWG above IOM recommendations, while 67.5% had GWG above the Intergrowth-21st standards. Multinomial logistic regression analysis showed that women with pre-pregnancy obesity and women with the highest body fat percentage had, respectively, a 95% (OR = 1.95; 95% CI: 1.08–3.51) and 1% (OR = 1.01; 95% CI: 1.01–1.05) higher chance of GWG above IOM recommendations. Pregnant women in the lowest tertile of height, smokers, number of previous pregnancies, and women living in crowded homes had, respectively, a 57% (OR = 0.57; 95% CI: 0.41–0.80), 36% (OR = 0.64; 95% CI: 0.37–0.86), 35% (OR = 0.65; 95% CI: 0.43–0.97), and 14% (OR = 0.86; 95% CI: 0.59–0.86) lower chance of GWG above IOM recommendations. Women with diabetes were 2.53 times more likely (OR = 2.53; 95% CI: 1.32–4.83) to have GWG below IOM recommendations. Using the Intergrowth-21st standards, women with the highest body fat percentage had a 12% (OR = 1.12; 95% CI: 1.02–1.24) higher chance of GWG above the 90th percentile. Pregnant women in the lowest tertile of height were 2.82 times more likely (OR = 2.82; 95% CI: 1.08–8.13) and women with the lowest hemoglobin concentrations had a 41% lower chance (OR = 0.59; 95% CI: 0.39–0.88) of having GWG below the 10th percentile. While both guidelines identified body fat percentage and pre-pregnancy obesity as significant predictors of excessive GWG, the Intergrowth-21st standards captured a higher percentage of women exceeding GWG limits.ConclusionThe findings underscore the importance of comparing two instruments for assessing the adequacy of GWG. The IOM and Intergrowth-21st standards provide complementary insights, which can help implement targeted interventions for specific groups of women based on their nutritional and socioeconomic status, lifestyle, and obstetric factors to prevent pregnancy-related complications.

Longitudinal study of birthweight, blood pressure, and markers of arterial stiffness in children age six among the TIDES cohort.

Although some studies have observed an association between birthweight and cardiovascular disease in adulthood, fewer have investigated whether birthweight is linked to cardiovascular health in early childhood. This study assesses the association between birthweight and cardiovascular outcomes in children 6 years of age. Birthweight, blood pressure (BP), and markers of arterial stiffness in children, including brachial artery distensibility and carotid-femoral pulse wave velocity (cfPWV), were obtained from 324 participants in The Infant Development and the Environment Study, a prospective multisite pregnancy cohort. Birthweight was converted into sex-specific birthweight-for-gestational-age (bw/ga) z -scores based on the INTERGROWTH-21st standard. Following 2017 American Academy of Pediatrics guidelines, SBP and DBP were transformed into sex, age, and height-specific z -scores. Associations between birthweight and cardiovascular outcomes were assessed using nested multivariable linear regression models among the overall and sex-stratified samples. Among the overall sample, bw/ga z -score was positively associated with cfPWV [b = 0.11 m/s, 95% confidence interval (CI): 0.01 m/s, 0.21 m/s] in crude and adjusted models. No associations between birthweight and cardiovascular outcomes were detected among the sex-stratified analyses. Overall, birthweight was not related to cardiovascular outcomes in children 6 years old. However, infants born with a higher birthweight may be at risk for higher cfPWV in childhood. Early intervention in pregnant people at risk of delivering high birthweight infants may be warranted if results are replicated.

Stillbirth risk by fetal size among 126.5 million births in 15 countries from 2000 to 2020: A fetuses-at-risk approach.

To compare stillbirth rates and risks for small for gestational age (SGA), large for gestational age (LGA) and appropriate for gestational age (AGA) pregnancies at 24-44 completed weeks of gestation using a birth-based and fetuses-at-risk approachs. Population-based, multi-country study. National data systems in 15 high- and middle-income countries. Live births and stillbirths. A total of 151 country-years of data, including 126 543 070 births across 15 countries from 2000 to 2020, were compiled. Births were categorised into SGA, AGA and LGA using INTERGROWTH-21st standards. Gestation-specific stillbirth rates, with total births as the denominator, and gestation-specific stillbirth risks, with fetuses still in utero as the denominator, were calculated from 24 to 44 weeks of gestation. Gestation-specific stillbirth rates and risks according to size at birth. The overall stillbirth rate was 4.22 per 1000 total births (95% CI 4.22-4.23) across all gestations. Applying the birth-based approach, the stillbirth rates were highest at 24 weeks of gestation, with 621.6 per 1000 total births (95% CI 620.9-622.2) for SGA pregnancies, 298.4 per 1000 total births (95% CI 298.1-298.7) for AGA pregnancies and 338.5 per 1000 total births (95% CI 337.9-339.0) for LGA pregnancies. Applying the fetuses-at-risk approach, the gestation-specific stillbirth risk was highest for SGA pregnancies (1.3-1.4 per 1000 fetuses at risk) prior to 29 weeks of gestation. The risk remained stable between 30 and 34 weeks of gestation, and then increased gradually from 35 weeks of gestation to the highest rate of 8.4 per 1000 fetuses at risk (95% CI 8.3-8.4) at ≥42 weeks of gestation. The stillbirth risk ratio (RR) was consistently high for SGA compared with AGA pregnancies, with the highest RR observed at ≥42 weeks of gestation (RR 9.2, 95% CI 15.2-13.2), and with the lowest RR observed at 24 weeks of gestation (RR 3.1, 95% CI 1.9-4.3). The stillbirth RR was also consistently high for SGA compared with AGA pregnancies across all countries, with national variability ranging from RR 0.70 (95% CI 0.43-0.97) in Mexico to RR 8.6 (95% CI 8.1-9.1) in Uruguay. No increased risk for LGA pregnancies was observed. Small for gestational age (SGA) was strongly associated with stillbirth risk in this study based on high-quality data from high- and middle-income countries. The highest RRs were seen in preterm gestations, with two-thirds of the stillbirths born as preterm births. To advance our understanding of stillbirth, further analyses should be conducted using high-quality data sets from low-income settings, particularly those with relatively high rates of SGA.

Intergrowth 21 Versus Fenton 2013 Growth Charts: Congruence in Assessing the Birth Size and the Proportion of Extra-uterine Growth Restriction in Preterm Babies

Background: Intergrowth-21st and Fenton 2013 growth charts are used for postnatal growth monitoring in preterms. There is no international consensus on which graph to refer to and why. This study is a local validation, of which graph would be plausible for the Indian population to detect small-for-gestational-age (SGA) and extra-uterine growth restriction (EUGR) babies, abetting in the settlement of this ambiguity. Objectives: The primary objective was to compare the Intergrowth-21st with Fenton 2013 growth charts for birth size classification and to detect the proportion of EUGR in preterms. The secondary objective was to assess the proportion of comorbidities in SGA babies by both these graphs. Methods: The design of the study was a prospective comparative observational study. All preterm newborns (24–<37 weeks of gestation) admitted to the neonatal intensive care unit of Noble Hospital and Research Center, Maharashtra, were the participants. Weight, length, and head circumference were plotted on Intergrowth 21 and Fenton growth charts at birth and at 4 weeks of age or at 36 weeks of postmenstrual age whichever is later. Corresponding Z-scores and percentiles were calculated electronically from their respective online software. Outcome: the reliability of Intergrowth-21st when compared to Fenton 2013 growth charts in assessing the birth size was better, and detection of the proportion of EUGR in preterm babies was better with Fenton charts. Results: A total of 429 preterm babies with a mean gestational age of 33.3 ± 2.4 weeks were included in the study. Fenton (67.1%) overestimated the proportion of EUGR when compared to Intergrowth-21st (18.6%) which was statistically significant (P < 0.001). On the contrary, although the proportion of SGA babies detected was higher with Intergrowth-21st (29.8%) when compared to Fenton (19.6%), there was moderate-to-high statistically significant agreement observed between the two growth charts in detecting SGA babies (Kappa = 0.716, P < 0.001). The proportion of comorbidities did not vary significantly among the SGA babies between the growth charts (P > 0.05). Conclusion: Fenton overestimates EUGR when compared to Intergrowth-21st, whereas both the growth charts are equally good in identifying SGA babies with no differences in the comorbidities detected. Intergrowth-21st standards look more pertinent for growth monitoring in the current study setting for Indian preterm babies.

Stillbirth Risk and Smallness for Gestational Age According to Hadlock, INTERGROWTH-21st, WHO, and GROW Fetal Weight Standards: Analysis by Maternal Ethnicity and Body Mass Index

(Abstracted from Am J Obstet Gynecol 2023;229:547.e1–13 Fetal growth during pregnancy is an important marker of fetal health, and fetal growth restriction (FGR) is highly correlated with stillbirth. To mitigate this risk, fetal growth must be assessed accurately and appropriately to recognize risk factors that point to FGR versus a normally developing fetus.

Selecting a birth weight standard for an indigenous population in a LMIC: A prospective comparative study.

The aim of the present study was to compare birth weight (BW) distribution and proportion of BWs below or above specified percentiles in low-risk singleton pregnancies in healthy South African (SA) women of mixed ancestry with expected values according to four BW references and to determine the physiological factors affecting BW. This was an ancillary study of a prospective multinational cohort study, involving 7060 women recruited between August 2007 and January 2015 in two townships of Cape Town, characterized by low socioeconomic status, and high levels of drinking and smoking. Detailed information about maternal and pregnancy characteristics, including harmful exposures, was gathered prospectively, allowing us to select healthy women with uncomplicated pregnancies without any known harmful exposures. In this cohort we compared the median BW and the proportion of BWs <P3, 5 and 10 or >P90, 95 and 97 according to four reference standards (INTERGROWTH-21st, customized according to the method described by Mickolajczyk, Fetal Medicine Foundation and revised Fenton reference) with expected values. Appropriate parametric and nonparametric tests were used, and sensitivity analysis was performed for infant sex, first trimester bookings and women of normal body mass index (BMI). Multiple regression was used to explore effects of confounders. Written consent and ethics approval was obtained. The cohort included 739 infants. The INTERGROWTH-21st standard was closest for the actual BW-distribution and categories. Below-expected BW was associated with boys, younger, shorter, leaner women, lower parity and gravidity. Actual BW was significantly influenced by maternal weight, BMI, parity and gestational age. Of the four references assessed in this study, the INTERGROWTH-21st standard was closest for the actual BW distribution. Maternal variables significantly influence BW.

Young Infant Mortality Associated with Preterm and Small-for-Gestational-Age Births in Rural Bangladesh: A Prospective Cohort Study

ObjectiveTo assess the relative risk of mortality in preterm and small-for-gestational-age (SGA) infants during the first and second months of life in rural Bangladesh. Study designWe analyzed data from a cohort of pregnant women and their babies in Sylhet, Bangladesh, assembled between 2011 and 2014. Community health workers visited enrolled babies up to 10 times from birth to age 59 days. Survival status was recorded at each visit. Gestational age was estimated from mother’s reported last menstrual period. Birth weights were measured within 72 hours of delivery. SGA was defined using the INTERGROWTH-21st standard. We estimated unadjusted and adjusted hazard ratios and corresponding 95% confidence intervals for preterm and SGA babies separately for the first and second month of life using bivariate and multivariable weighted Cox regression models. ResultsThe analysis included 17,643 singleton live birth babies. Compared with term-AGA infants, in both unadjusted and adjusted analyses, preterm-SGA infants had the highest risk of death in the first (HR 13.25, 95% CI 8.65 - 20.31; AHR 12.05, 95% CI 7.82 - 18.57) and second month of life (HR 4.65; 95% CI 1.93 - 11.23; AHR 4.1, 95% CI 1.66 - 10.15), followed by preterm-AGA infants, and term-SGA. ConclusionsThe risk of mortality in preterm and/or SGA is increased for newborns and extends through the second month of life. Appropriate interventions to prevent and manage complications due to prematurity and SGA could improve survival during and beyond the neonatal period.

Intrauterine Transmission of Zika and Vertical Transfer of Neutralizing Antibodies Detected Immediately at Birth in Oaxaca, Mexico: An Analysis in the Context of Microcephaly.

Zika virus (ZIKV) can cause neurological issues in infants. To provide protection, neutralizing antibodies should be transferred from the mother to the infant. We conducted a study at the Hospital General de Pochutla, Oaxaca, Mexico. Samples were collected from mothers (blood and breast milk) and infants (saliva and dried blood spots) within the first 12 postnatal hours (December 2017 to February 2018) and tested for ZIKV total and neutralizing antibodies as well as ZIKV-PCR. Microcephaly was evaluated according to INTERGROWTH-21st standards. Maternal IgG seroprevalence was 28.4% with 10.4% active infection, while infant IgG seroprevalence was 5.5% with 2.4% active infection. There were two cases of virolactia, and 6.3% of the infant saliva samples tested positive for ZIKV. Additionally, 18.3% of the infants were in a cephalic perimeter percentile lower than 10 and had an association between microcephaly and serology or a PCR between 8.6 and 60.9%. The infant blood samples had neutralizing antibodies, indicating intrauterine protection. Microcephaly was correlated with serology or PCR, but in our study population, non-ZIKV factors may be involved as well. Low ZIKV infection values in breast milk mean that breastfeeding is safe in most of the mothers and infants of the endemic area studied.

Vulnerable newborn phenotypes in Peru: a population-based study of 3,841,531 births at national and subnational levels from 2012 to 2021

We aimed to examine the national and subnational prevalence of vulnerable newborn phenotypes in Peru, 2012-2021. Newborn phenotypes were defined using gestational age (preterm [PT], term [T]), birthweight for gestational age using INTERGROWTH-21st standards (small for gestational age [SGA], appropriate for gestational age [AGA] or large for gestational age [LGA]), and birthweight (low birthweight [LBW], non-LBW) using the Peruvian National Birth Registry as six (by excluding birthweight) and ten newborn phenotypes (using all three outcomes). Small phenotypes (with at least one classification of PT, SGA, or LBW) were further considered. Using individual-level data, we stratified the phenotypes by maternal educational level, maternal age, healthcare insurance, altitude of residence, and geographic region (Coast, Andes, and Amazon). The prevalence of the five vulnerable newborn phenotypes for the study period was LGA+T (15.2%), AGA+PT (5.2%), SGA+T (4.6%), LGA+PT (0.8%), and SGA+PT (0.7%). The Coast had a higher prevalence of newborns with large phenotypes (19.4%) and the Highlands a higher prevalence of newborns with small phenotypes (12.5%). Mothers with poor socioeconomic status, extreme ages and living at high altitude had a higher prevalence of newborns with small phenotypes, and mothers who were wealthier, more educated, and older had a higher prevalence of infants with large phenotypes. Our findings cautiously suggest that socioeconomic and geographic disparities may play a crucial role in shaping vulnerable newborn phenotypes at national and subnational level in Peru. Further studies using longitudinal data are needed to corroborate our findings and to identify individual-level risk factors. Ter Meulen Grant from the KNAW Medical Sciences Fund of the Royal Netherlands Academy of Arts and Sciences (KNAWWF/1085/TMB406, KNAWWF/1327/TMB202116), Fogarty Program (D43TW011502).

Growth Status of Full-Term Infants with Different Sizes for Gestational Age During the First Year of Life.

This study aimed to assess the growth of full-term infants with different sizes at birth and examine catch-up and catch-down growth in their first year. This retrospective population-based cohort study was based on the Guangdong Provincial Women and Children Health Information System. 194797 full-term singleton live births were extracted. Measurements for weight and length were taken at birth, 6 months, and 12 months. The size-for-gestational age was categorized as small (SGA, <10th centile), appropriate (AGA, 10th-90th centiles), or large (LGA, >90th centile) based on the international newborn size for gestational age and sex INTERGROWTH-21st standards. Catch-up and catch- down growth were defined as a change in standard deviation in z-score greater than 0.67 in the growth curves. Of the 194797 full-term singletons, the average gestational age was 39.28 ± 1.03 weeks, and the average weight of the newborns was 3205 ± 383 grams. 15632 infants were identified as SGA (8.0%) and 12756 were LGA (6.5%). At 1 year of age, catch-up growth in weight was observed in 63.0% of SGA infants, 29.5% of AGA infants, and 5.4% of LGA infants. Conversely, catch-down growth occurred in 3.3% of SGA infants, 17.8% of AGA infants, and 54.7% of LGA infants. The proportions of catch-up growth in length for SGA, AGA, and LGA infants within the first year were 31.4%, 22.5%, and 17.1%, respectively. Catch-up or catch-down growth predominantly occurred before 6 months of age. However, from 6 to 12 months, there was no significant variation in WAZ among children with different birth sizes. In their first year of life, full-term singleton live births tend towards regression to the mean in their postnatal weight and length. The average delay in the growth of LGA is compensated by an increase in it of the SGA. Early monitoring and intervention are crucial for optimizing growth in infants with different birth sizes.

Comparison of Intergrowth-21st and Fenton growth standards to evaluate and predict the postnatal growth in eastern Chinese preterm infants

ObjectivesThe aim of this article was to compare the differences between Intergrowth-21st (IG-21) and Fenton growth standards in the classification of intrauterine and extrauterine growth restriction (EUGR) in eastern Chinese preterm infants, and detect which one can better relate to neonatal diseases and predict the physical growth outcomes at 3–5 years old.MethodsPremature infants admitted to a tertiary pediatric hospital in Shanghai, China, from 2016 to 2018 were enrolled. Prenatal information, neonatal diseases during hospitalization, and anthropometric data (weight, height, and head circumference) at birth and at discharge were collected and analyzed. Physical growth outcomes (short stature, thinness, and overweight) were examined by telephone investigations in 2021 at age 3–5 years.ResultsThe medium gestational age and birth weight of the included 1,065 preterm newborns were 33.6 weeks and 1,900 g, respectively. The IG-21 curves diagnosed more newborns with small for gestational age (SGA) (19% vs. 14.7%) and fewer newborns with longitudinal EUGR on height (25.5% vs. 27.9%) and head circumference (17.9% vs. 24.7%) compared to Fenton curves. Concordances between Fenton and IG-21 standards were substantial or almost perfect in the classification of SGA and longitudinal EUGR, but minor in cross-sectional EUGR. EUGR identified by Fenton curves was better related to neonatal diseases than IG-21 curves. There were no statistical significances in the prediction of short stature, thinness, and overweight at 3–5 years old between the two charts.ConclusionsIG-21 growth standards are not superior to Fenton in assessing preterm growth and development in the eastern Chinese population.

Fetal growth assessed via ultrasound in relation to maternal HIV infection status and antiretroviral regimens.

To evaluate effects of maternal HIV and antiretroviral treatment (ART) on intrauterine fetal growth. Prospective cohort studies of HIV and ZIKA infection among women living with HIV (WLHIV) and women not living with HIV (WNLHIV) conducted in Brazil and the US from 2016 to 2020. We evaluated fetal growth via repeated ultrasounds and calculated z scores for fetal growth measures using Intergrowth-21st standards among women with singleton pregnancies. Adjusted linear mixed models were fit for each fetal growth z score by HIV status. Among WLHIV, we compared fetal growth z scores by the most common maternal ART regimens, stratified by timing of ART initiation. We included 166 WLHIV and 705 WNLHIV; none had Zika infection. The z scores were similar for WLHIV and WNLHIV for femur length (latest third trimester median = 1.08) and estimated fetal weight (median ≈0.60); adjusted mean differences in fetal weight z scores by HIV status were less than 0.1 throughout gestation. Other fetal growth measurements were lower for WLHIV than WNLHIV early in gestation but increased more rapidly over gestation. Among WLHIV not on ART at conception, adjusted mean z scores were generally similar across regimens initiated during pregnancy but somewhat lower for atazanavir-based regimens for biparietal diameter compared with efavirenz-based or raltegravir-based regimens. Among WLHIV on ART at conception, mean z scores were similar across ART regimens. Within our cohorts, fetal growth was lower in WLHIV than WNLHIV early in gestation but similar by the end of gestation, which is reassuring. Among WLHIV, fetal growth measures were generally similar across ART regimens evaluated.

Small for gestational age and early childhood caries: the BRISA cohort study

This study tests the hypothesis that children 12–30 months born small for gestational age (SGA) aged are more susceptible to severe early childhood caries (S-ECC). We used data on 865 children aged 12–30 months from a prospective cohort study conducted in a city in the northeast of Brazil. The study outcome was S-ECC, defined based on the proportion of decayed tooth surfaces (cavitated or not). The main exposure variable was SGA, defined according to the Kramer criterion and the INTERGROWTH-21st standard. Direct (SGA → S-ECC) and indirect effects were estimated using structural equation modeling, calculating standardized factor loadings (SFL) and P-values (alpha = 5%). The final models showed a good fit. SGA influenced S-ECC in the direct and indirect paths. In the group of SGA children with 12 or more erupted teeth defined according to the Kramer criterion, the direct effect was positive (SFL = 0.163; P = 0.019); while among all SGA children defined according to the INTERGROWTH-21st standard, the direct effect was negative (SFL = − 0.711; P < 0.001). Age and number of erupted teeth may influence the occurrence of S-ECC in SGA children, as the number of teeth affects the time of exposure to disease risk factors.

Risk factors for inadequate and excessive gestational weight gain in 25 low- and middle-income countries: An individual-level participant meta-analysis.

Many women experience suboptimal gestational weight gain (GWG) in low- and middle-income countries (LMICs), but our understanding of risk factors associated with GWG in these settings is limited. We investigated the relationships between demographic, anthropometric, lifestyle, and clinical factors and GWG in prospectively collected data from LMICs. We conducted an individual participant-level meta-analysis of risk factors for GWG outcomes among 138,286 pregnant women with singleton pregnancies in 55 studies (27 randomized controlled trials and 28 prospective cohorts from 25 LMICs). Data sources were identified through PubMed, Embase, and Web of Science searches for articles published from January 2000 to March 2019. Titles and abstracts of articles identified in all databases were independently screened by 2 team members according to the following eligibility criteria: following inclusion criteria: (1) GWG data collection took place in an LMIC; (2) the study was a prospective cohort or randomized trial; (3) study participants were pregnant; and (4) the study was not conducted exclusively among human immunodeficiency virus (HIV)-infected women or women with other health conditions that could limit the generalizability of the results. The Institute of Medicine (IOM) body mass index (BMI)-specific guidelines were used to determine the adequacy of GWG, which we calculated as the ratio of the total observed weight gain over the mean recommended weight gain. Study outcomes included severely inadequate GWG (percent adequacy of GWG <70), inadequate GWG (percent adequacy of GWG <90, inclusive of severely inadequate), and excessive GWG (percent adequacy of GWG >125). Multivariable estimates from each study were pooled using fixed-effects meta-analysis. Study-specific regression models for each risk factor included all other demographic risk factors measured in a particular study as potential confounders, as well as BMI, maternal height, pre-pregnancy smoking, and chronic hypertension. Risk factors occurring during pregnancy were further adjusted for receipt of study intervention (if any) and 3-month calendar period. The INTERGROWTH-21st standard was used to define high and low GWG among normal weight women in a sensitivity analysis. The prevalence of inadequate GWG was 54%, while the prevalence of excessive weight gain was 22%. In multivariable models, factors that were associated with a higher risk of inadequate GWG included short maternal stature (<145 cm), tobacco smoking, and HIV infection. A mid-upper arm circumference (MUAC) of ≥28.1 cm was associated with the largest increase in risk for excessive GWG (risk ratio (RR) 3.02, 95% confidence interval (CI) [2.86, 3.19]). The estimated pooled difference in absolute risk between those with MUAC of ≥28.1 cm compared to those with a MUAC of 24 to 28.09 cm was 5.8% (95% CI 3.1% to 8.4%). Higher levels of education and age <20 years were also associated with an increased risk of excessive GWG. Results using the INTERGROWTH-21st standard among normal weight women were similar but attenuated compared to the results using the IOM guidelines among normal weight women. Limitations of the study's methodology include differences in the availability of risk factors and potential confounders measured in each individual dataset; not all risk factors or potential confounders of interest were available across datasets and data on potential confounders collected across studies. Inadequate GWG is a significant public health concern in LMICs. We identified diverse nutritional, behavioral, and clinical risk factors for inadequate GWG, highlighting the need for integrated approaches to optimizing GWG in LMICs. The prevalence of excessive GWG suggests that attention to the emerging burden of excessive GWG in LMICs is also warranted.

Stillbirth risk and smallness for gestational age according to Hadlock, INTERGROWTH-21st, WHO, and GROW fetal weight standards: analysis by maternal ethnicity and body mass index

Appropriate growth charts are essential for fetal surveillance, to confirm that growth is proceeding normally and to identify pregnancies that are at risk. Many stillbirths are avoidable through antenatal detection of the small-for-gestational-age fetus. In the absence of an international consensus on which growth chart to use, it is essential that clinical practice reflects outcome-based evidence. This study investigated the performance of 4 internationally used fetal weight standards and their ability to identify stillbirth risk in different ethnic and maternal size groups of a heterogeneous population. We analyzed routinely collected maternity data from more than 2.2 million pregnancies. Three population-based fetal weight standards (Hadlock, Intergrowth-21st, and World Health Organization) were compared with the customized GROW standard that was adjusted for maternal height, weight, parity, and ethnic origin. Small-for-gestational-age birthweight and stillbirth risk were determined for the 2 largest ethnic groups in our population (British European and South Asian), in 5 body mass index categories, and in 4 maternal size groups with normal body mass index (18.5-25.0 kg/m2). The differences in trend between stillbirth and small-for-gestational-age rates were assessed using the Clogg z test, and differences between stillbirths andbody mass index groups were assessed using the chi-square trend test. Stillbirth rates (per 1000) were higher in South Asian pregnancies (5.51) than British-European pregnancies (3.89) (P<.01) and increased in both groups with increasing body mass index (P<.01). Small-for-gestational-age rates were 2 to 3-fold higher for South Asian babies than British European babies according to the population-average standards (Hadlock: 26.2% vs 12.2%; Intergrowth-21st: 12.1% vs 4.9%; World Health Organization: 32.2% vs 16.0%) but were similar by the customized GROW standard (14.0% vs 13.6%). Despite the wide variation, each standard's small-for-gestation-age cases had increased stillbirth risk compared with non-small-for-gestation-age cases, with the magnitude of risk inversely proportional to the rate of cases defined as small for gestational age. All standards had similar stillbirth risk when the small-for-gestation-age rate was fixed at 10% by varying their respective thresholds for defining small for gestational age. When analyzed across body mass index subgroups, the small-for-gestation-age rate according to the GROW standard increased with increasing stillbirth rate, whereas small-for-gestation-age rates according to Hadlock, Intergrowth-21st, and World Health Organization fetal weight standards declined with increasing body mass index, showing a difference in trend (P<.01) to stillbirth rates across body mass index groups. In the normal body mass index subgroup, stillbirth rates showed little variation across maternal size groups; this trend was followed by GROW-based small-for-gestation-age rates, whereas small-for-gestation-age rates defined by each population-average standard declined with increasing maternal size. Comparisons between population-average and customized fetal growth charts require examination of how well each standard identifies pregnancies at risk of adverse outcomes within subgroups of any heterogeneous population. In both ethnic groups studied, increasing maternal body mass index was accompanied by increasing stillbirth risk, and this trend was reflected in more pregnancies being identified as small for gestational age only by the customized standard. In contrast, small-for-gestation-age rates fell according to each population-average standard, thereby hiding the increased stillbirth risk associated with high maternal body mass index.

Vulnerable newborn types: analysis of subnational, population-based birth cohorts for 541 285 live births in 23countries, 2000-2021.

To examine prevalence of novel newborn types among 541 285 live births in 23 countries from 2000 to 2021. Descriptive multi-country secondary data analysis. Subnational, population-based birth cohort studies (n = 45) in 23 low- and middle-income countries (LMICs) spanning 2000-2021. Liveborn infants. Subnational, population-based studies with high-quality birth outcome data from LMICs were invited to join the Vulnerable Newborn Measurement Collaboration. We defined distinct newborn types using gestational age (preterm [PT], term [T]), birthweight for gestational age using INTERGROWTH-21st standards (small for gestational age [SGA], appropriate for gestational age [AGA] or large for gestational age [LGA]), and birthweight (low birthweight, LBW [<2500 g], nonLBW) as ten types (using all three outcomes), six types (by excluding the birthweight categorisation), and four types (by collapsing the AGA and LGA categories). We defined small types as those with at least one classification of LBW, PT or SGA. We presented study characteristics, participant characteristics, data missingness, and prevalence of newborn types by region and study. Among 541 285 live births, 476 939 (88.1%) had non-missing and plausible values for gestational age, birthweight and sex required to construct the newborn types. The median prevalences of ten types across studies were T+AGA+nonLBW (58.0%), T+LGA+nonLBW (3.3%), T+AGA+LBW (0.5%), T+SGA+nonLBW (14.2%), T+SGA+LBW (7.1%), PT+LGA+nonLBW (1.6%), PT+LGA+LBW (0.2%), PT+AGA+nonLBW (3.7%), PT+AGA+LBW (3.6%) and PT+SGA+LBW (1.0%). The median prevalence of small types (six types, 37.6%) varied across studies and within regions and was higher in Southern Asia (52.4%) than in Sub-Saharan Africa (34.9%). Further investigation is needed to describe the mortality risks associated with newborn types and understand the implications of this framework for local targeting of interventions to prevent adverse pregnancy outcomes in LMICs.

Vulnerable newborn types: Analysis of population-based registries for 165 million births in 23 countries, 2000-2021.

To examine the prevalence of novel newborn types among 165 million live births in 23 countries from 2000 to 2021. Population-based, multi-country analysis. National data systems in 23 middle- and high-income countries. Liveborn infants. Country teams with high-quality data were invited to be part of the Vulnerable Newborn Measurement Collaboration. We classified live births by six newborn types based on gestational age information (preterm <37 weeks versus term ≥37 weeks) and size for gestational age defined as small (SGA, <10th centile), appropriate (10th-90th centiles), or large (LGA, >90th centile) for gestational age, according to INTERGROWTH-21st standards. We considered small newborn types of any combination of preterm or SGA, and term + LGA was considered large. Time trends were analysed using 3-year moving averages for small and large types. Prevalence of six newborn types. We analysed 165 017 419 live births and the median prevalence of small types was 11.7% - highest in Malaysia (26%) and Qatar (15.7%). Overall, 18.1% of newborns were large (term + LGA) and was highest in Estonia 28.8% and Denmark 25.9%. Time trends of small and large infants were relatively stable in most countries. The distribution of newborn types varies across the 23 middle- and high-income countries. Small newborn types were highest in west Asian countries and large types were highest in Europe. To better understand the global patterns of these novel newborn types, more information is needed, especially from low- and middle-income countries.

Influence of Gestational Age Correction and Shape-Based Trajectories in the Identification of Children’s Growth Patterns From Birth to 11 Years

ObjectivesChildhood growth reflects nutritional status such as under- or overnutrition and is a determinant of life health. Thus, early detection of sub-optimal growth patterns can help identify modifiable risk factors. Current approaches rely on the trajectory intercept and struggle to capture differences in trajectory shape, which better reflects change over time. This study implemented a novel approach to identify shape-based growth patterns in children from birth to 11 years of age. MethodsWe used anthropometric measures from 3,945 children at postnatal age 3 months, 1, 2, 4, 6 and 11 years from the 2004 Pelotas Birth Cohort (Brazil). Weight-, height- and BMI-for-age Z-scores were calculated using INTERGROWTH21st and WHO growth standards. The impact of gestational age-correction (CA) in preterm-born children (n = 461) was tested, and trajectories were either baseline anchored at zero or not. This produced 4 analytical pipelines for pattern detection (k-means, Frechet’s distance): 1) no CA–no baseline anchoring; 2) no CA–with baseline anchoring; 3) with CA–no baseline anchoring; 4) with CA–with baseline anchoring. ResultsWe found 3 patterns for each Z-score, with “High” (increasing), “Middle” (stable) and “Low” (declining) trajectories. The use of both CA and baseline anchoring highlighted sub-groups of children with specific patterns related to early growth (first 3 months of life). In the non-anchored approach, CA influenced the mean trajectories detected by increasing the intercept and reducing the slope between birth and 3 months. Baseline anchoring identified mean trajectories with steeper slopes during this period, thus, capturing differential growth patterns in early life. ConclusionsDepending on the question, incorporating CA with or without baseline anchoring when analyzing growth patterns can better highlight aspects of early growth versus overall patterns across childhood and can improve growth analyses standardization in population-based studies. Funding SourcesJoannah and Brian Lawson Centre for Child Nutrition, Lawson Family Chair in Microbiome Nutrition Research, CONACyT scholarship, Wellcome Trust, World Health Organization, National Support Program for Centers of Excellence, Brazilian National Research Council, Brazilian Ministry of Health, and Children’s Pastorate.

A novel shape-based approach to identify gestational age-adjusted growth patterns from birth to 11 years of age

Child growth patterns assessment is critical to design public health interventions. However, current analytical approaches may overlook population heterogeneity. To overcome this limitation, we developed a growth trajectories clustering pipeline that incorporates a shape-respecting distance, baseline centering (i.e., birth-size normalized trajectories) and Gestational Age (GA)-correction to characterize shape-based child growth patterns. We used data from 3945 children (461 preterm) in the 2004 Pelotas Birth Cohort with at least 3 measurements between birth (included) and 11 years of age. Sex-adjusted weight-, length/height- and body mass index-for-age z-scores were derived at birth, 3 months, and at 1, 2, 4, 6 and 11 years of age (INTERGROWTH-21st and WHO growth standards). Growth trajectories clustering was conducted for each anthropometric index using k-means and a shape-respecting distance, accounting or not for birth size and/or GA-correction. We identified 3 trajectory patterns for each anthropometric index: increasing (High), stable (Middle) and decreasing (Low). Baseline centering resulted in pattern classification that considered early life growth traits. GA-correction increased the intercepts of preterm-born children trajectories, impacting their pattern classification. Incorporating shape-based clustering, baseline centering and GA-correction in growth patterns analysis improves the identification of subgroups meaningful for public health interventions.

Assessment of physical development healthy full-term newborns of the Republic of Crimea centile standards INTERGROWTH-21&lt;sup&gt;st&lt;/sup&gt;

Objective: to determine the feasibility of using INTERGROWTH-21st centile tables in assessing the physical development of full-term newborns in the Republic of Crimea. Materials and methods: a retrospective analysis of 1300 birth histories of full-term newborns whose mothers permanently reside on the territory of the Republic of Crimea was carried out. Mass and length, chest and chest circumference were analyzed. The assessment of the obtained anthropometric indicators was carried out by the centile method according to the INTERGROWTH-21st tables. In the study, we conducted a comparative assessment using the accepted INTERGROWTH-21st standards, comparing them with the accepted domestic assessments of the state of the physical development of newborns. Results: the values of anthropometric indicators of boys in the Republic of Crimea are shifted towards higher estimates. Estimates “below average”, “low”, “very low” are found in no more than 3% of cases. “Above average”, “high”, “very high” are much more common: with 10% — for weight/length ratio, 18% — for weight, 34% — for length, and 51% — for head circumference. The values of anthropometric indicators of girls in the Republic of Crimea are also biased towards higher estimates. Ratings of “below average”, “low”, “very low” are very rare: 6% — for the weight/length ratio, 4% — for the weight rating, less than 1% — for the body length rating and 2% — for the head circumference. “Above average”, “high”, “very high” scores are much more common: 8% — for weight/length ratio, 15% — for weight score, 45% — for length score, and 30%— for OH. Conclusions: we consider the use of centile tables INTERGROWTH-21st in assessing the physical development of full-term newborns of the Republic of Kazakhstan to be inappropriate and we see the need to develop regional standards.