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.

This study aimed to investigate how maternal birthweight is related to early pregnancy obesity, gestational diabetes mellitus (GDM), and offspring birthweight. Females born term and singleton in Sweden between 1973 and 1995 (N = 305,893) were studied at their first pregnancy. Information regarding their birthweight, early pregnancy body mass index, and pregnancy complications was retrieved from the Swedish Medical Birth Register, as were data on their mothers and offspring. High maternal birthweights (2–3 standard deviation scores (SDS) and >3 SDS) were associated with greater odds of early pregnancy obesity, odds ratio (OR) 1.52 (95% confidence interval (CI) 1.42–1.63) and OR 2.06 (CI 1.71–2.49), respectively. A low maternal birthweight (<2 SDS) was associated with greater odds of GDM (OR 2.49, CI 2.00–3.12). No association was found between high maternal birthweight and GDM. A maternal birthweight 2–3 SDS was associated with offspring birthweight 2–3 SDS (OR 3.83, CI 3.44–4.26), and >3 SDS (OR 3.55, CI 2.54–4.97). Corresponding ORs for a maternal birthweight >3 SDS were 5.38 (CI 4.12–7.01) and 6.98 (CI 3.57–13.65), respectively. In conclusion, a high maternal birthweight was positively associated with early pregnancy obesity and offspring macrosomia. A low, but not a high maternal birthweight, was associated with GDM.

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.

Low birth weight (LBW) and macrosomia have been associated with later-in-life metabolic alterations. The aim of this study was to elucidate whether the expression levels of circulating microRNAs (c-miRNAs) associated with adult metabolic diseases are also dysregulated in newborns with LBW or macrosomia. The expression levels of five microRNAs (miRNAs) associated with metabolic diseases were quantified in dried blood spots of newborns with adequate birth weight, LBW and macrosomia by stem-loop real-time polymerase chain reaction. miR-29a-5p, miR-126-3p, miR-221-3p, and miR-486-5p were significantly overexpressed in newborns with macrosomia and showed no significant change in the LBW group compared to normal weight controls. miR-320a showed no statistical difference among groups. We predicted the putative target genes and pathways of the overexpressed miRNAs with bioinformatic tools. Bioinformatic analyses of overexpressed miRNAs predicted target genes involved in carbohydrate metabolism, participate in FoxO and PI3K/Akt signaling pathways, and are associated with diabetes, obesity, and cardiovascular diseases. The overexpression of circulating miR-29a-5p, miR-126-3p, miR-221-3p, and miR-486-5p may explain the increased risk of obesity and diabetes associated with macrosomia. The use of dried blood spots from newborn screening cards to quantify miRNAs expression levels could be an early and minimally invasive predictive tool for these metabolic alterations.

It has been suggested that the risk of adverse perinatal outcomes in twin pregnancies is exacerbated by concomitant gestational diabetes mellitus (GDM). This study aimed to assess the risk incurred by twin pregnancy and by a diagnosis of GDM, separately, on the development of poor perinatal outcomes. A retrospective cohort study was conducted on all pregnant women at a tertiary center between 2016 and 2017. The impact of GDM and twin pregnancies on perinatal outcomes — birth weight above the 90th centile for gestational age, cesarean delivery, clinical neonatal hypoglycemia, and premature delivery (before 37 weeks’ gestation) — was assessed using univariate and multivariate analyses. Overall, 13,527 women were eligible for the study; 11,915 were uncomplicated singleton pregnancies; 1379 of these had GDM; 194 were twin pregnancies, and 39 of these had GDM. Univariate analyses showed that twin pregnancies were associated with a higher risk of all perinatal outcomes except macrosomia. In the multivariate analyses, twin pregnancy was a much higher predictor of cesarean delivery (OR 8.40, 95% CI [6.25, 11.49], p < .0001) and preterm birth (OR 58.82, 95% CI [31.25, 125], p < .0001) compared to GDM but GDM was a higher predictor of neonatal hypoglycemia (OR 4.87, 95% CI [3.74, 6.29], p < .0001). Twin pregnancy is more strongly associated with all adverse perinatal outcomes except macrosomia. GDM does not increase risk of adverse perinatal outcomes except for neonatal hypoglycemia.

Macrosomia, not only is closely associated with short-term, birth-related problems, but also has long-term consequences for the offspring. We investigated the expression of long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) in the placenta of macrosomia births using a microarray profile. The data showed that 2929 lncRNAs and 4574 mRNAs were upregulated in the placenta of macrosomia births compared with the normal birth weight group (fold change ⩾2.0, P<0.05), and 2127 lncRNAs and 2511 mRNAs were downregulated (fold change ⩾2.0, P<0.05). To detect the function of the differentially expressed lncRNAs and their possible relationship with the differentially expressed mRNAs, we also performed gene ontology analysis and pathway analysis. The results demonstrated that the PI3K-AKT signalling pathway, the mitogen-activated protein kinase (MAPK) signalling pathway, the focal adhesion pathway, the B cell receptor signalling pathway, and the protein processing in endoplasmic reticulum and lysosome pathway were significantly differentially expressed in the macrosomia placenta. Four lncRNAs were randomly chosen from the differentially expressed lncRNAs to validate the microarray data by quantitative polymerase chain reaction (qPCR). The qPCR results were consistent with the microarray data. In conclusion, lncRNAs were significantly differentially expressed in the placenta of macrosomia patients, and may contribute to the pathogenesis of macrosomia.

The present study is a secondary analysis of the ROLO study, a randomised control trial of a low-glycaemic index (GI) diet in pregnancy to prevent the recurrence of fetal macrosomia. The objectives of the present study were to identify which women are most likely to respond to a low-GI dietary intervention in pregnancy with respect to three outcome measures: birth weight; maternal glucose intolerance; gestational weight gain (GWG). In early pregnancy, 372 women had their mid-upper arm circumference recorded and BMI calculated. Concentrations of glucose, insulin and leptin were measured in early pregnancy and at 28 weeks. At delivery, infant birth weight was recorded and fetal glucose, C-peptide and leptin concentrations were measured in the cord blood. Women who benefited in terms of infant birth weight were shorter, with a lower education level. Those who maintained weight gain within the GWG guidelines were less overweight in both their first and second pregnancies, with no difference being observed in maternal height. Women who at 28 weeks of gestation developed glucose intolerance, despite the low-GI diet, had a higher BMI and higher glucose concentrations in early pregnancy with more insulin resistance. They also had significantly higher-interval pregnancy weight gain. For each analysis, women who responded to the intervention had lower leptin concentrations in early pregnancy than those who did not. These findings suggest that the maternal metabolic environment in early pregnancy is important in determining later risks of excessive weight gain and metabolic disturbance, whereas birth weight is mediated more by genetic factors. It highlights key areas, which warrant further interrogation before future pregnancy intervention studies, in particular, maternal education level and inter-pregnancy weight gain.

Gestational diabetic mellitus (GDM) pregnancies have an increased risk of macrosomic infants and large placental mass, though the mechanisms explaining each of these is uncertain. We sought to evaluate the contribution of apoptosis to placental size and the expression of glucose transporters (SLC2A) in GDM pregnancies. Maternal age and pre-pregnancy body weight were documented. Newborn weights were recorded after delivery. Placentas 37–40-week gestation from control patients (no pregnancy complication) (n = 5), or with GDM (n = 5) were weighed immediately after delivery. Villous samples (4 mm diameter) were collected and divided into specimens; one was fixed in 4% paraformaldehyde for immunostaining using terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling (TUNEL) and activated caspase-3. The other specimen was snap frozen in liquid nitrogen and stored at −80°C for active caspase-3, poly(ADP-ribose) polymerase (PARP), SLC2A1 and SLC2A3 gene expression analysis. Our results showed that maternal age and pre-pregnancy body weight were significantly higher in the GDM group when compared with those from the controls (P < 0.05). The mean neonatal birth weight and placenta weight were significantly higher in the GDM group compared with that from the controls (P < 0.05). The apoptotic index of placentas (0.05 ± 0.01 v. 0.17 ± 0.04, P < 0.04), active caspase-3 polypeptide fragments and PARP protein were significantly decreased in GDM placentas as compared with controls. Further, the level of placental SLC2A1 protein expression was ∼3-fold higher in GDM placentas. Our results suggest that reduced apoptosis in GDM placentas may contribute to increased placental tissue, which together with enhanced SLC2A1 expression, could play a role in fetal macrosomia.

Infant birth weight has increased in Ireland in recent years along with levels of childhood overweight and obesity. The present article reviews the current literature on maternal glycaemia and the role of the dietary glycaemic index (GI) and its impact on pregnancy outcomes. It is known that maternal weight and weight gain significantly influence infant birth weight. Fetal macrosomia (birth weight >4000 g) is associated with an increased risk of perinatal trauma to both mother and infant. Furthermore, macrosomic infants have greater risk of being obese in childhood, adolescence and adulthood compared to normal-sized infants. There is evidence that there is a direct relationship between maternal blood glucose levels during pregnancy and fetal growth and size at birth, even when maternal blood glucose levels are within their normal range. Thus, maintaining blood glucose concentrations within normal parameters during pregnancy may reduce the incidence of fetal macrosomia. Maternal diet, and particularly its carbohydrate (CHO) type and content, influences maternal blood glucose concentrations. However, different CHO foods produce different glycaemic responses. The GI was conceived by Jenkins in 1981 as a method for assessing the glycaemic responses of different CHO. Data from clinical studies in healthy pregnant women have documented that consuming a low-GI diet during pregnancy reduces peaks in postprandial glucose levels and normalises infant birth weight. Pregnancy is a physiological condition where the GI may be of particular relevance as glucose is the primary fuel for fetal growth.