The objective of this prospective observational study was to assess the growth and body composition of term small-for-gestational-age (SGA) infants from birth to 6 months and evaluate the effect of catch-up growth (CUG) on body composition. Term SGA newborns were recruited at birth. Anthropometry and body composition were evaluated at 3 days, 6, 10 and 14 weeks, and 6 months. Fat and fat-free mass (FM and FFM) were compared between infants with and without CUG (increase in weight Z-score by > 0·67) by air displacement plethysmography. Factors that could affect body composition and CUG, including parents’ BMI and stature, infants’ birth weight, sex and feeding, were evaluated. A total of 143 SGA newborns (sixty-six boys) with birth weight of 2336 (sd 214) g were enrolled; 109 were followed up till 6 months. Median weight Z-score increased from −2·3 at birth to −1·3 at 6 months, with 51·9 % of infants showing CUG. Infants with CUG had higher FM (1796 (sd 491) g v. 1196 (sd 474) g, P < 0·001) but similar FFM (4969 (sd 508) g v. 4870 (sd 622) g, P = 0·380), and consequently higher FM percentage (FM%) (26·5 (sd 5·8) v. 19·7 (sd 6·9), P < 0·001), compared with those without CUG. Lower birth weight, exclusive breast-feeding and higher parental stature were positively associated with CUG. In conclusion, CUG in term SGA infants in the first 6 months of life was almost entirely attributable to greater gain in FM. Follow-up of this cohort will provide insight into the long-term effect of disproportionate gain in FM in early infancy in SGA babies.

This study aimed to evaluate the association between parental and infant birth weights in Japan. In total, 37,504 pregnant Japanese women and their partners were included in this birth cohort study. A multinomial logistic regression model was used to evaluate the associations of parental birth weights with small-for-gestational-age (SGA) or large-for-gestational-age (LGA) infants. Associations between parental birth weight and low birth weight (LBW) infants or macrosomia were also examined, and linear associations between parental birth weight and SGA or LGA were found. The adjusted odds ratios (aORs) for SGA infants per 500 g decrease in maternal and paternal birth weights were 1.50 (95% confidence interval [CI],1.43–1.58) and 1.31 (95% CI, 1.25–1.38), respectively. The aORs for LGA infants per 500 g increase in maternal and paternal birth weights were 1.53 (95% CI, 1.47–1.60) and 1.41 (95% CI, 1.35–1.47), respectively. The association between parental birth weight and LBW infants or macrosomia was also linear. The aORs for LBW infants per 500 g decrease in maternal and paternal birth weights were 1.47 (95% CI, 1.40–1.55) and 1.25 (95% CI, 1.19–1.31), respectively. The aORs for macrosomia per 500 g increase in maternal and paternal birth weights were 1.59 (95% CI, 1.41–1.79) and 1.40 (95% CI, 1.23–1.60), respectively. Parental birth weight was found to be associated with infant birth weight even after adjusting for various parental factors. Furthermore, maternal birth weight was more strongly associated with infant birth weight than with paternal birth weight.

Late preterm (LP, born between 34 0/7 and 36 6/7 weeks of gestation) infants may experience several adverse outcomes, similar to those experienced by low birthweight (LBW, birthweight <2500 g) infants. However, while LP infants are often born with LBW, the association between LP and LBW remains unknown. This study aimed to investigate LBW rate and independent risk factors for LBW in LP singleton neonates. We retrospectively analyzed data of LP singleton neonates, born between 2013 and 2017, from the Japan Society of Obstetrics and Gynecology Successive Pregnancy Birth Registry System. The exclusion criteria included stillbirths and infants with missing data. Logistic regression analyses were performed to investigate maternal and perinatal factors associated with LBW in LP singletons. LBW was observed in 62.5% (n = 35,113) of 56,160 LP singleton births. In the multiple logistic regression analysis, LBW in LP neonates was independently associated with modifiable maternal factors, including pre-pregnancy underweight, inadequate gestational weight gain, and smoking during pregnancy, as well as non-modifiable factors, including younger maternal age, nulliparity, hypertensive disorder of pregnancy, preeclampsia, cesarean section delivery, and female offspring. According to the Japanese pregnancy birth registry data, more than half of LP neonates were LBW. We previously discussed the issue of LBW regarding infants with different backgrounds, as there are many different causes of LBW. Several risk factors should be subdivided and considered for the risk of LP and LBW.

Small for gestational age (SGA) is typically defined as birth weight < 10th percentile for age. Limited data are available regarding the growth of SGA preterm infants in relation to feeding type. We aimed to study SGA preterm infants fed fortified mother’s own milk (MOM) or preterm formula (PF) on growth patterns and catch-up growth at discharge and 2-year corrected age (CA). Our retrospective cohort study included data from medical records and follow-up questionnaires about SGA preterm infants born at < 37 weeks fed on MOM (n 40) and PF (n 40). Weight, length/height and head circumference (HC) were collected at birth, discharge and at 2-year CA, and Δ z-scores were calculated. The MOM group had significantly larger negative change in weight and length z-scores between birth and discharge, and smaller positive change in HC z-score (–0·47 (sd 0·41) v. −0·25 (sd 0·36), P = 0·01; −0·63 (sd 0·75) v. −0·27 (sd 0·75), P = 0·03; 0·13 (sd 0·67) v. 0·41 (sd 0·55), P = 0·04, respectively). Almost half of the MOM-fed infants experienced poor length growth by discharge compared with 22 % of PF-fed infants (P = 0·03). By 2-year CA, both groups had similar positive change in weight and HC z-scores, but MOM-fed infants had a slower increase in height z-score (0·64 (sd 1·30) v. 1·33 (sd 1·33), P = 0·02), and only 40 % had achieved catch-up height compared with 68 % of the PF group (P = 0·02). Our study indicates that fortified MOM-fed SGA preterm infants may need extra nutritional support in the first 2 years of life to achieve height growth potential.

Prenatal exposure to dichlorodiphenyldichloroethylene (p,p´-DDE) may interfere with fetal development; however, studies evaluating anthropometry and gestational age at birth show inconsistent results. Typically, p,p´-DDE exposure has been measured during the third trimester and missed the key early pregnancy period. We evaluated the association between p,p´-DDE exposure before week 18 of pregnancy and anthropometry at birth, as well as gestational length, in 170 mother–child pairs from a cohort study in a flower-growing mexican region. Maternal serum p,p´-DDE concentrations were determined by gas chromatography. The associations between p,p´-DDE and z-scores of birth weight, birth length, and gestational age were evaluated by linear multiple regression models. Logistic regression models were used for low birth weight and small size for gestational age. Effect modification by child’s sex was explored. The average gestational age at the blood sample extraction was 10.6 weeks. p,p'-DDE was detected in 64.7% of mothers, at a geometric mean of 0.24 ng/mL. Prenatal p,p´-DDE exposure was not associated with the birth outcomes in the whole sample. However, a high p,p´-DDE exposure was marginally associated with greater small for gestational age risk in male newborns (OR≥0.076 ng/mL vs <0.076 ng/mL = 3.09, 95% CI: 0.61; 15.58), but not in female (p for interaction = 0.08).

Even though, we found no reductions in anthropometric measurements or gestational length associated with early prenatal p,p´-DDE exposure, the potential effect modification by infant’s sex in terms of small for the gestational age risk deserves future studies.

This study aimed to describe diet quality of pregnant women and explore the association between maternal diet and the prevalence of low birth weight (LBW) and small for gestational age (SGA). A total of 3856 participants from a birth cohort in Beijing, China, were recruited between June 2018 and February 2019. Maternal diet in the first and second trimesters was assessed by the Chinese diet balance index for pregnancy (DBI-P), using data collected by the inconsecutive 2-d 24-h dietary recalls. Logistic regressions were performed to explore the independent effects of DBI-P components on LBW and SGA. The prevalence of LBW and SGA was 3·8% and 6·0%, respectively. Dietary intakes of the participants were imbalanced. The proportions of participants having insufficient intake of vegetables (87·3% and 86·6%), dairy product (95·9% and 96·7%) and aquatic foods (80·5% and 85·3%) were high in both trimesters. The insufficiency of fruit intake was more severe in the second (85·2%) than that in the first trimester (22·5%) (P < 0·05). After adjusting for potential confounders, the intake of fruits and dairy in the second trimester was negatively associated with the risk of LBW (OR = 0·850, 95% CI: 0·723, 0·999) and SGA (OR = 0·885, 95% CI: 0·787, 0.996), respectively. Sufficient consumption of fruits and dairy products in pregnancy may be suggested in order to prevent LBW and SGA.

This study aimed to investigate the association between hyperemesis gravidarum (HG) severity and early enteral tube feeding on cardiometabolic markers in offspring cord blood. We included women admitted for HG, who participated in the MOTHER randomised controlled trial (RCT) and observational cohort. The MOTHER RCT showed that early enteral tube feeding in addition to standard care did not affect symptoms/birth outcomes. Among RCT and cohort participants, we assessed how HG severity affected lipid, c-peptide, glucose and free thyroxine cord blood levels. HG severity measures were severity of vomiting at inclusion and 3 weeks after inclusion, pregnancy weight gain and 24-h energy intake at inclusion, readmissions and duration of hospital admissions. Cord blood measures were also compared between RCT participants allocated to enteral tube feeding and those receiving standard care. Between 2013-2016, 215 women were included: 115 RCT and 100 cohort participants. Eighty-one cord blood samples were available. Univariable not multivariable regression analysis showed that lower maternal weight gain was associated with higher cord blood glucose levels (β: –0·08, 95% CI –0·16, –0·00). Lower maternal weight gain was associated with higher Apo-B cord blood levels in multivariable regression analysis (β: –0·01, 95% CI –0·02, –0·01). No associations were found between other HG severity measures or allocation to enteral tube feeding and cord blood cardiometabolic markers. In conclusion, while lower maternal weight gain was associated with higher Apo-B cord blood levels, no other HG severity measures were linked with cord blood cardiometabolic markers, nor were these markers affected by enteral tube feeding.

Evidence of couples’ BMI and its influence on birth weight is limited and contradictory. Therefore, this study aims to assess the association between couple’s preconception BMI and the risk of small for gestational age (SGA)/large for gestational age (LGA) infant, among over 4·7 million couples in a retrospective cohort study based on the National Free Pre-pregnancy Checkups Project between 1 December 2013 and 30 November 2016 in China. Among the live births, 256 718 (5·44 %) SGA events and 506 495 (10·73 %) LGA events were documented, respectively. After adjusting for confounders, underweight men had significantly higher risk (OR 1·17 (95 % CI 1·15, 1·19)) of SGA infants compared with men with normal BMI, while a significant and increased risk of LGA infants was obtained for overweight and obese men (OR 1·08 (95 % CI 1·06, 1·09); OR 1·19 (95 % CI 1·17, 1·20)), respectively. The restricted cubic spline result revealed a non-linear decreasing dose–response relationship of paternal BMI (less than 22·64) with SGA. Meanwhile, a non-linear increasing dose–response relationship of paternal BMI (more than 22·92) with LGA infants was observed. Moreover, similar results about the association between maternal preconception BMI and SGA/LGA infants were obtained. Abnormal preconception BMI in either women or men were associated with increased risk of SGA/LGA infants, respectively. Overall, couple’s abnormal weight before pregnancy may be an important preventable risk factor for SGA/LGA infants.

Intrauterine preeclampsia exposure affects the lifelong cardiometabolic health of the child. Our study aimed to compare the growth (from birth to 6 months) of infants exposed to either a normotensive pregnancy or preeclampsia and explore the influence of being born small for gestational age (SGA). Participants were children of women participating in the Post-partum, Physiology, Psychology and Paediatric follow-up cohort study. Birth and 6-month weight and length z-scores were calculated for term and preterm (<37 weeks) babies, and change in weight z-score, rapid weight gain (≥0.67 increase in weight z-score) and conditional weight gain z-score were calculated. Compared with normotensive exposed infants (n = 298), preeclampsia exposed infants (n = 84) were more likely to be born SGA (7% versus 23%; P < 0.001), but weight gain from birth to 6 months, by any measure, did not differ between groups. Infants born SGA, irrespective of pregnancy exposure, were more likely to have rapid weight gain and had greater increases in weight z-score compared with those not born SGA. Preeclampsia exposed infants born SGA may benefit from interventions designed to prevent future cardiometabolic disease.

The effects of supraphysiological estradiol (E2) on neonatal outcomes and the significance of specific E2 concentrations remain unclear. The purpose of this study was to investigate whether supraphysiological E2 levels on the human chorionic gonadotropin (hCG) trigger day are associated with small size for gestational age (SGA) in singletons born from fresh embryo transfer (ET) cycles. Patients with singleton pregnancies who delivered after the transfer of fresh embryos, during the period from July 2012 to December 2017, at our center were included. We excluded cycles involving a vanishing twin, maternal age >35 years, basal follicle-stimulating hormone ≥10 mIU/ml, or anti-Müllerian hormone ≤1 ng/ml. We then divided all cycles into five groups by E2 level on trigger day: group A, <2000 pg/ml (reference group); group B, 2000 pg/ml≤E2<2999 pg/ml; group C, 3000 pg/ml≤E2<3999 pg/ml; group D, 4000 pg/ml≤E2<4999 pg/ml; and group E, ≥5000 pg/ml. The prevalence of SGA among singletons from fresh ET was the primary outcome. The SGA rate significantly increased when the E2 level was ≥4000 pg/ml, as observed by comparing groups D (odds ratio [OR]: 1·79, 95% confidence interval [CI]: 1·16–2·76, P = 0·01) and E (OR: 1·68, 95% CI: 1·10–2·56, P = 0·02) with the reference group. Multivariate logistic regression indicated that a serum E2 level of at least 4000 pg/ml on the hCG trigger day was associated with increased SGA and with significant differences for groups D (adjusted OR [AOR]: 1·65, 95% CI: 1·05–2·59, P = 0·03) and E (AOR: 1·60, 95% CI: 1·03–2·53, P = 0·04) relative to the reference group. In conclusion, in fresh ET cycles, the supraphysiological E2 ≥4000 pg/ml on the hCG trigger day increases the risk of SGA.

Inadequate nutrition during a critical period of development – as is the case during gestation and the first days of life, especially in very-low-birth-weight (VLBW) infants, can impact on neurodevelopment and favour co-morbidities. In this study, we evaluate how neurodevelopment may be affected by intra-uterine growth (IUGR) restriction and by an inadequate intake of nutritional energy during the early neonatal period. A longitudinal cohort study was conducted to analyse the nutritional contributions received during the first week of life, among a population of 396 VLBW infants. Motor, cognitive, sensory and behavioural development was assessed at 14, 25, 33 and 50 months. The association between IUGR, postnatal energy restriction and neurodevelopment was examined using multivariate logistic regression techniques. Mild cognitive delay was observed in 35·6 % of neonates with IUGR and in 24 % of those with appropriate birth weight. IUGR is associated with behavioural disorder (OR 2·60; 95 % CI 1·25, 5·40) and delayed cognitive development (OR 2·64; 95 % CI 1·34, 5·20). Energy restriction during the first week of life is associated with visual deficiency (OR 2·96; 95 % CI 1·26, 6·84) and cerebral palsy (OR 3·05; CI 95 % 1·00, 9·54). In VLBW infants, IUGR is associated with behavioural disorder, while postnatal energy restriction is significantly associated with motor disorder, infantile cerebral palsy and sensory disorder.

Fat-soluble vitamins during pregnancy are important for fetal growth and development. The present study aimed at exploring the association between vitamin A, E and D status during pregnancy and birth weight. A total of 19 640 women with singleton deliveries from a retrospective study were included. Data were collected by the hospital electronic information system. Maternal serum vitamin A, E and D concentrations were measured during pregnancy. Logistic regression was performed to estimate the association between the vitamin status and low birth weight (LBW) or macrosomia. Women with excessive vitamin E were more likely to have macrosomia (OR 1·30, 95 % CI 1·07, 1·59) compared with adequate concentration. When focusing on Z scores, there was a positive association between vitamin E and macrosomia in the first (OR 1·07, 95 % CI 1·00, 1·14), second (OR 1·27, 95 % CI 1·11, 1·46) and third (OR 1·28, 95 % CI 1·06, 1·54) trimesters; vitamin A was positively associated with LBW in the first (OR 1·14, 95 % CI 1·01, 1·29), second (OR 1·31, 95 % CI 1·05, 1·63) and third (OR 2·00, 95 % CI 1·45, 2·74) trimesters and negatively associated with macrosomia in the second (OR 0·79, 95 % CI 0·70, 0·89) and third (OR 0·77, 95 % CI 0·62, 0·95) trimesters. The study identified that high concentrations of vitamin E are associated with macrosomia. Maintaining a moderate concentration of vitamin A during pregnancy might be beneficial to achieve optimal birth weight. Further studies to explore the mechanism of above associations are warranted.

Despite high altitude was implicated in adverse birth outcomes, there remained a paucity of evidence on low-to-medium altitude effect. This study aimed to explore the association of low-to-medium altitude with birth outcomes. A population-based cross-sectional survey was performed using a stratified multistage random sampling method among women with their infants born during 2010–2013 in Northwestern China. Altitude was determined in meters based on the village or community of the mother’s living areas. Birth outcomes involved birth weight, gestational age, and small for gestational age (SGA). Generalized linear models were fitted to investigate the association of altitude with birth outcomes. Moreover, the dose–response relationship between altitude and birth outcomes was evaluated with a restricted cubic spline function. A total of 27 801 women with their infants were included. After adjusting for potential confounders, every 100-m increase in the altitude was associated with reduced birth weight by 6.4 (95% CI −8.1, −4.6) g, the slight increase of gestational age by 0.015 (95% CI 0.010, 0.020) week, and an increased risk of SGA birth (odds ratio 1.03, 95% CI 1.02, 1.04). Moreover, there was an inversely linear relationship between altitude and birth weight (P for overall < 0.001 and P for nonlinear = 0.312), and a positive linear relationship between altitude and SGA (P for overall < 0.001 and P for nonlinear = 0.194). However, a nonlinear relationship was observed between altitude and gestational age (P for overall < 0.001 and P for nonlinear = 0.010). The present results suggest that low-to-medium altitude is possibly associated with adverse birth outcomes.

Sleep-disordered breathing (SDB) worsens over pregnancy, and obstructive sleep apnea is associated with serious maternal complications. Intrauterine exposures that provoke insulin resistance (IR), inflammation, or oxidative stress may have long-term offspring health consequences. In obesity, worsening maternal SDB appears to be an exposure that increases the risk for both small- or large-for-gestational-age (SGA, LGA, respectively), suggesting distinct outcomes linked to a common maternal phenotype. The aim of this paper is to systematically review and link data from both mechanistic rodent models and descriptive human studies to characterize the impact of maternal SDB on fetal development. A systematic review of the literature was conducted using PubMed, Embase, and CINAHL (01/2000–09/2019). Data from rodent (9 studies) and human models (48 studies, 5 meta-analyses) were included and reviewed using PRISMA guidelines. Evidence from rodent models suggests that intermittent maternal hypoxia results in mixed changes in birth weight (BW) followed by accelerated postnatal growth, while maternal sleep fragmentation results in normal BW followed by later metabolic derangement. Human studies support that maternal SDB is associated with both SGA and LGA, both of which may predispose offspring to later obesity. Evidence also suggests a link between SDB, inflammation, and oxidative stress that may impact maternal metabolism and/or placental function. SDB is common in pregnancy and affects fetal growth and development. Given that SDB has significant potential to adversely influence the intrauterine metabolic environment, larger, prospective studies in humans are urgently needed to fully elucidate the effects of this exposure on offspring metabolic risk.

Previous studies have shown conflicting findings regarding the relationship between maternal vitamin D deficiency (VDD) and fetal growth restriction (FGR). We hypothesised that parathyroid hormone (PTH) may be an underlying factor relevant to this potential association. In a prospective birth cohort study, descriptive statistics were evaluated for the demographic characteristics of 3407 pregnancies in the second trimester from three antenatal clinics in Hefei, China. The association of the combined status of vitamin D and PTH with birth weight and the risk of small for gestational age (SGA) was assessed by a multivariate linear and binary logistic regression. We found that declined status of 25-hydroxyvitamin D is associated with lower birth weight (for moderate VDD: adjusted β = −49·4 g, 95 % CI −91·1, −7·8, P < 0·05; for severe VDD: adjusted β = −79·8 g, 95 % CI −127·2, −32·5, P < 0·01), as well as ascended levels of PTH (for elevated PTH: adjusted β = −44·5 g, 95 % CI −82·6, −6·4, P < 0·05). Compared with the non-VDD group with non-elevated PTH, pregnancies with severe VDD and elevated PTH had the lowest neonatal birth weight (adjusted β = −124·7 g, 95 % CI −194·6, −54·8, P < 0·001) and the highest risk of SGA (adjusted risk ratio (RR) = 3·36, 95 % CI 1·41, 8·03, P < 0·01). Notably, the highest risk of less Ca supplementation was founded in severe VDD group with elevated PTH (adjusted RR = 4·67, 95 % CI 2·78, 7·85, P < 0·001). In conclusion, elevated PTH induced by less Ca supplementation would further aggravate the risk of FGR in pregnancies with severe VDD through impaired maternal Ca metabolism homoeostasis.

Few studies have investigated the association between maternal dietary patterns (DP) during pregnancy, derived from reduced-rank regression (RRR), and fetal growth. This study aims to identify DP during pregnancy associated with macro- and micronutrient intakes, using the RRR method, and to examine their relationship with birth weight (BW). We used data of 7194 women from a large-scale cross-sectional survey in Northwest China. Dietary protein, carbohydrate, haem Fe density and the ratio of PUFA and MUFA:SFA were used as the intermediate variables in the RRR model to extract DP. Generalised estimating equation models were applied to evaluate the associations between DP and BW and related outcomes (including BW z-score, low birth weight (LBW) and small for gestational age (SGA)). Four DP during pregnancy were identified. Socio-demographically disadvantaged pregnant women were more likely to have lower BW and lower adherence to DP1 (high legumes, soyabean products, vegetables and animal-source foods, with relative low wheat and oils). Women with medium and high adherence to DP1 had significantly increased BW (medium 28·6 (95 % CI 7·1, 50·1); high 25·2 (95 % CI 2·7, 47·6)) and BW z-score and had significantly reduced risks of LBW and SGA. The associations were stronger among women with babies <3100 g. There is no association between other DP and outcomes. Higher adherence to the DP that was high in legumes, soyabean products, vegetables and animal-source foods was associated with improved BW in the Chinese pregnant women, particularly among those with disadvantageous socio-demographic conditions.