Newborn Body Mass Research Articles

Higher and bigger: How riparian bats react to climate change

The altitudinal distribution of animals and changes in their body size are effective indicators of climate change. Bats are sensitive to climate change due to their dependence on temperature during critical life stages. However, long-term studies documenting responses over extended periods are rare. We present a 24-year investigation of Myotis daubentonii, a riparian bat known for altitudinal sexual segregation, along a river course in Central Italy. While males occupy the entire river course, females are confined to downstream warmer areas supporting successful reproduction due to improved foraging site productivity. In 2000, females were absent above 900 m a.s.l in our study area. We hypothesise that a) this altitude threshold is now higher, due to thermal gradient changes along the river course; and b) thermoregulatory costs for reproductive females have declined, leading to increased energy investment in offspring and subsequent generational growth in bat body size. Confirming our hypotheses, females exhibited a 175-m upward shift in altitude limit. Furthermore, we found a concurrent increase in body size (but not condition). Temperatures increased in the 24 years, likely allowing females to extend their range to higher elevations and favouring an increase in newborn body mass. Riparian vegetation remained unchanged, excluding habitat quality changes as the cause for the observed responses. The rapid female elevation rise might imply future disruption of established social structures, altering intra- and intersexual competition for roosts and food. Given the global decline in insect populations, larger bats might face future difficulties in finding food to sustain their body size, increasing mortality. However, the full impact of such changes on bat fitness remains unexplored and warrants further investigation, including other bat populations. This knowledge is crucial for informing conservation in the face of ongoing climate change and preserving the ecosystem services bats deliver in riparian ecosystems.

THADA, SDHAF4, and MACF1 Gene Polymorphisms and Placental Expression in Women with Gestational Diabetes.

Gestational diabetes mellitus (GDM) is a metabolic disorder in pregnant women leading to various complications. Consequently, factors predisposing its development are being sought. Previous studies have shown that the pathogenesis of GDM is similar to that of type 2 diabetes, and it is therefore thought that the two diseases may have a common genetic basis. The aim of this study was to examine the associations between thyroid adenoma-associated (THADA) rs7578597 T>C, succinate dehydrogenase complex assembly factor 4 (SDHAF4) rs1048886 A>G, and microtubule-actin crosslinking factor 1 (MACF1) rs2296172 A>G gene polymorphisms and the risk of GDM development as well as selected clinical parameters in women with GDM. We also examined the expression of these genes in the placenta of women with and without GDM in association with clinical parameters. This case-control study included 272 pregnant women with GDM and 348 pregnant women with normal glucose tolerance. There were no statistically significant differences in the distribution of the THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G gene polymorphisms between pregnant control women and women with GDM. The associations between clinical parameters such as body mass before pregnancy, body mass at birth, body mass increase during pregnancy, BMI before pregnancy, BMI at birth, BMI increase during pregnancy, glycated hemoglobin (HbA1c), daily insulin requirement, childbirth time, and newborn body mass and APGAR score, and the THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G genotypes were statistically non-significant. We only observed lower values of body mass before pregnancy and body mass at birth in women with the SDHAF4 rs1048886 AG genotype in comparison with AA genotype carriers. There was no statistically significant difference in the expression of THADA, SDHAF4, and MACF1 genes in the placenta between women with GDM and healthy women. There were also no statistically significant correlations between THADA, SDHAF4, and MACF1 gene expression in the placenta and clinical parameters. The results of our study suggest that THADA rs7578597 T>C, SDHAF4 rs1048886 A>G, and MACF1 rs2296172 A>G gene polymorphisms are not significant factors associated with GDM onset. In addition, SDHAF4 rs1048886 A>G may be associated with body mass before pregnancy and body mass at birth in pregnant women.

Obstetric adaptation of the human pelvic inlet based on a sample of females and males matched for body size, and comparison with three species of primates that are sexually monomorphic in body size.

Human males are larger than females in body size; females are larger than males in pelvic size. Percentage pelvic sexual size dimorphism (sex with larger mean/sex with lower mean*100%) is used to infer selection for obstetric adaptation. As pelvic size is associated with body size, interpretation of percentage sexual size dimorphism necessitates control of body size. This study uses a larger sample of 221 females and 204 males to identify a subsample of females and males matched for femoral length, femoral head diameter, and clavicular length (25 females, 46 males). For five measures of the pelvic inlet, the human sample with control of body size is compared with three primate species that are sexually monomorphic in body size and give birth to newborns with higher relative body masses than those of humans: Aotus azarae (15 females, 19 males), Hylobates lar (29 females, 29 males), and Saguinus geoffroyi (28 females, 30 males). Results show that humans (112.0%) have the highest percentage sexual size dimorphism of pelvic inlet circumference: A. azarae (108.2%), H. lar (105.4%), and S. geoffroyi (103.3%). Humans have higher sexual size dimorphism of inlet circumference despite lower relative newborn body mass compared to the other species because human newborns are of larger body mass than predicted for an anthropoid with our adult female body mass. In humans, birthing of bigger babies than predicted for our body mass increases selection pressure on females for enlargement of the pelvic inlet.

PPARG, TMEM163, UBE2E2, and WFS1 Gene Polymorphisms Are Not Significant Risk Factors for Gestational Diabetes in the Polish Population.

Gestational diabetes mellitus (GDM) is a common disorder that occurs in pregnant women, leading to many maternal and neonatal complications. The pathogenesis of GDM is complex and includes risk factors, such as: age, obesity, and family history of diabetes. Studies have shown that genetic factors also play a role in the pathogenesis of GDM. The present study investigated whether polymorphisms in the PPARG (rs1801282), TMEM163 (rs6723108 and rs998451), UBE2E2 (rs6780569), and WFS1 (rs4689388) genes are risk factors for the development of GDM and whether they affect selected clinical parameters in women with GDM. This study included 204 pregnant women with GDM and 207 pregnant women with normal glucose tolerance (NGT). The diagnosis of GDM was based on a 75 g oral glucose tolerance test (OGTT) at 24–28 weeks gestation, according to the International Association of Diabetes and Pregnancy Study Groups (IADPSG) criteria. There were no statistically significant differences in the distribution of polymorphisms studied between women with GDM and pregnant women with normal carbohydrate tolerance, which suggests that these polymorphisms are not risk factors for GDM. We also examined the associations between studied gene polymorphisms and clinical parameters: fasting glucose, daily insulin requirement, body mass before pregnancy, body mass at birth, body mass increase during pregnancy, BMI before pregnancy, BMI at birth, BMI increase during pregnancy, new-born body mass, and APGAR score in women with GDM. We observed lower BMI values before pregnancy and at birth in women with PPARG rs17036160 TT genotype. The results of this study suggest that the PPARG (rs1801282), TMEM163 (rs6723108 and rs998451), UBE2E2 (rs6780569), and WFS1 (rs4689388) gene polymorphisms are not significant risk factors for GDM development in the Polish population and do not affect the clinical parameters in women with GDM; only rs1801282 of the PPARG gene may influence BMI values in women with GDM.

Shearing during late pregnancy increases size at birth but does not alter placental endocrine responses in sheep

Shearing during the latter half of pregnancy is a common practice to improve flock health and productivity. Previous studies have demonstrated that shearing pregnant ewes at mid or late pregnancy is associated with an increase in lamb birth weight. In the present study, we used singleton Polypay × Dorset pregnant sheep, to investigate the potential roles of placental function and changes in maternal metabolism in underlying this increased birth weight response. Two groups were randomly established and blocked at enrollment by animal BW, body condition score and subcutaneous adipose tissue depth. The groups were shorn (SH; n = 18) or not (C; n = 20) at gestational day (GD) 107 ± 1 (mean ± SEM). Weekly maternal plasma samples were collected between shearing and birth, but only six samples were assayed for progesterone, pregnancy-associated glycoproteins (PAG1), glucose and non-esterified fatty acids (NEFAs). At birth, sex, birth weight, and newborn body mass index (BMI) were recorded. Maternal BW during mid- to late-pregnancy was similar between groups. Shearing resulted in increased lamb birth weight and BMI (P < 0.05) regardless of fetal sex but did not affect the maternal concentration of PAG1 or progesterone from GDs 100 to 142. After shearing (GD100) and up to lambing, shorn females had higher circulating glucose concentrations (P < 0.05), but not NEFA, compared to the control group. Maternal circulating PAG1, progesterone, glucose or NEFA concentration across pregnancy did not differ according to lamb sex. Across pregnancy, birth weight was positively associated with PAG1 (P < 0.001), but not with progesterone concentrations. In conclusion, weight and BMI at birth were higher in both sexes upon shearing in singleton pregnancies. Despite PAG1 being associated with birth weight, late-pregnancy shearing did not alter the placental endocrine response. Whether other placental factors are altered upon shearing and may influence the increase in birth weight and BMI remain to be investigated.

Associations between glucokinase and glucokinase regulatory protein gene polymorphisms and clinical parameters in pregnant women

ABSTRAKTWstęp: Ciąża wiąże się ze zmianami w metabolizmie węglowodanów, które mogą wywierać wpływ na noworodka. Podstawowym macierzyńskim czynnikiem środowiskowym, który reguluje wzrost płodu, jest dostarczanie substratu do łożyska, a glukoza jest głównym substratem energetycznym do wzrostu wewnątrzmacicznego. Podstawowym źródłem glukozy są węglowodany z diety. Glukokinaza (GCK) jest enzymem odpowiedzialnym za regulację wychwytu i magazynowania glukozy. Białko regulatorowe glukinazy (GCKR) moduluje glukokinazę, która katalizuje wątrobową fosforylację glukozy, prowadząc do syntezy glikogenu i triacylogliceroli.Celem badania była ocena związku między polimorfizmami GCK rs1799884 i GCKR rs780094 a parametrami klinicznymi u kobiet w ciąży.Materiały i metody: Do badania włączono 207 kobiet w ciąży z prawidłowymi wartościami doustnego testu tolerancji glukozy (OGTT). Przeanalizowano związek między badanymi polimorfizmami a parametrami klinicznymi takimi jak: masa ciała przed ciążą, masa ciała przy porodzie, wzrost masy ciała w czasie ciąży, wskaźnik masy ciała (BMI) przed ciążą, BMI przy porodzie, wzrost BMI w trakcie ciąży, czas trwania ciąży, masa ciała noworodka, wynik w skali APGAR i stężenia glukozy dla OGTT.Wyniki i wnioski: Nie stwierdzono zależności istotnych statystycznie między polimorfizmami GCK rs1799884 i GCKR rs780094 a badanymi parametrami klinicznymi, z wyjątkiem wyższego wzrostu BMI podczas ciąży u kobiet z genotypem CC GCK rs1799884.

CCL2, CCL5, IL4 and IL15 Gene Polymorphisms in Women with Gestational Diabetes Mellitus.

Gestational diabetes mellitus (GDM) is a glucose intolerance that occurs during pregnancy. Several studies suggest that inflammation contributes to pregnancy-induced insulin resistance and the development of glucose intolerance. The aim of this study is to examine the association between the CCL2, CCL5, IL4 and IL15 gene polymorphisms and the development of GDM. This study included 411 pregnant women who underwent a 75 g oral glucose tolerance test at 24-28 weeks of gestation. Participants were categorised into 2 groups according to results of the oral glucose tolerance test (OGTT). The GDM group included 204 pregnant women who were diagnosed with GDM. The normal glucose tolerance group included 207 pregnant women with normal values in the OGTT. To discriminate the CCL2 rs1024611 and rs4586, CCL5 rs2107538, IL4 rs2243250, IL15 rs2857261 and rs2254514 alleles, TaqMan® Pre-Designed SNP Genotyping Assays were used. GDM was significantly associated with genotypes and alleles of the CCL2 rs1024611 and rs4586 polymorphisms, while there was no statistically significant association between the CCL5 rs2107538, IL4 rs2243250, IL15 rs2857261, and rs2254514 gene polymorphisms and GDM. In a multivariate regression analysis, age and BMI before pregnancy were independent significant predictors of a higher risk of GDM, while a lower number of G alleles CCL2 rs1024611 was protective against GDM. Moreover, women with the GG CCL2 rs1024611 and CC rs4586 genotype tended to have lower body mass and BMI increases during pregnancy, as well as lower newborn body mass. The results of our study suggest an association between CCL2 gene polymorphisms and GDM.

Pelvic sexual dimorphism among species monomorphic in body size: relationship to relative newborn body mass.

Females have larger pelves than males among eutherians to mitigate obstetrical difficulty. This study addresses 3 issues concerning pelvic sexual dimorphism using 8 species that are sexually monomorphic in nonpelvic size: Aotus azarae , Castor canadensis , Dasypus novemcinctus , Hylobates lar , Saguinus geoffroyi , Sciurus carolinensis , Sylvilagus floridanus , and Urocyon cinereoargenteus . Using published data to compute the index of relative newborn body mass (RNBM = [newborn body mass/adult female body mass]100%) for 266 eutherian species, A. azarae , H. lar , and S. geoffroyi are characterized as giving birth to relatively large newborns and the other 5 species as giving birth to relatively small newborns. The 3 issues are, compared to species giving birth to relatively small newborns, whether species that give birth to relatively large newborns have 1) higher magnitude of pelvic sexual size dimorphism (SSD), 2) lower prevalence of pelvic joint fusion, and 3) dissociation between pelvic and nonpelvic sizes. Nine measures of the pelvis were taken, and fusion of interpubic and sacroiliac joints was observed. Species grouped by high and low RNBM do not differ significantly in magnitude of SSD of pelvic inlet circumference. Species with high RNBM have significantly lower prevalence of interpubic joint fusion than those with low RNBM. Sexes do not differ in their multiple correlation coefficients between inlet circumference and nonpelvic body size in 7 of 8 species. Results suggest that 1) there are multiple anatomical pathways for pelvic obstetrical sufficiency, 2) an unfused interpubic joint is obstetrically advantageous, and 3) relative newborn size does not change the association between pelvic and nonpelvic size in females and males.

Elements in placenta and pregnancy outcome in arctic and subarctic areas

Objectives. This paper describes a comprehensive assessment of the association of concentrations of essential and toxic elements in maternal and neonatal body fluids and the placenta as predictors of birth weight and newborn body mass index (BMIC) for deliveries in northern Norway and Russia.Study design. A prospective cross-sectional study of delivering women and their outcomes from different locations in Russian and Norwegian arctic and sub-arctic areas.Methods. Life-style information, blood, urine and placenta specimens were collected for 50 consecutive mother-infant pairs from hospital delivery departments in a total of six communities located in Finnmark, Norway, or the western arctic/subarctic regions of Russia. Questionnaire information was collected by individual interviews performed by trained health personnel. Pregnancy outcomes were verified by consulting medical records. Cadmium, copper, iron (as ferritin), nickel, lead, selenium and zinc were measured in maternal blood, serum or maternal urine; and in cord blood, or neonatal urine and placental tissue. Univariate and multivariate linear regression analysis and ANOVA were employed to explore associations between these clinical chemistry outcomes and birth weight and BMIC.Results. A number of significant relationships were evident between: placental and maternal blood cadmium (p < 0.005); cord and maternal blood lead (p < 0.001); placental and maternal blood lead (p < 0.001); placental and cord-blood lead (p < 0.001); placental and maternal serum, or blood, selenium (p < 0.001); and placental and maternal serum copper (p < 0.001). Maternal body mass index (BMI), maternal age, placental lead, or maternal blood lead, and smoking were retained as predictors of birth weight and BMIC in the multivariate modelling. Birth weights in both countries were normally distributed.Conclusions. Maternal age and BMI as positive predictors of birth weight, and cigarette smoking and lead exposure as negative determinants, are discussed in terms of established evidence and recognized confounders, including maternal genetic factors, socio-economic status, socio-political change, life-style issues, prenatal care and nutrition. It is recommended that future work in societies undergoing socio-economic transition might best focus on preventive measures to improve neonatal health and development. (Int J Circumpolar Health 2004; 63(2):169–187)

Concentrations of essential trace elements in maternal serum and the effect on birth weight and newborn body mass index in sub-arctic and arctic populations of Norway and Russia

This project is part of an assessment of the impact of environmental factors on human health in the Kola Peninsula of Russia and the neighboring arctic area of Norway. Pregnant women and their newborns were studied to explore a relationship between maternal status of essential metals and birth weight. Life-style information and serum specimens were collected from at least 50 consecutive mother-infant pairs from hospital delivery departments in three Russian and three Norwegian communities (N=151 and 167, respectively). Pregnancy outcomes were verified by consulting medical records. Copper, selenium and zinc in serum were determined by atomic absorption spectrometry and ferritin by an automated analyzer method. Mean birth weight and child's body mass index (BMIC) were significantly lower in the Russian group (p<0.001), with or without adjustment for gestational age. Copper, iron (as ferritin) and selenium serum concentrations were in the normal range, while zinc levels in both countries were mostly below the lower limit (10.8 micromol/L) of reported reference intervals. A positive correlation between zinc and birth weight or BMIC was only observed for concentrations exceeding 10.8 micromol/L. Analysis by quartiles showed that maternal urinary creatinine and birth weight were negatively correlated (p=0.001). The influence of the different elements on BMIC, grouped by quartiles, was significantly positive only for selenium (p=0.03) and ferritin (p=0.02), while there was no significant relationship for copper or zinc. Adjustment of birth weight and BMIC for gestational age did not alter substantially the various associations indicated. With the exception of zinc, the mineral status of delivering women in arctic and sub-arctic regions of Norway and western Russia appears to be adequate. The significantly lower BMIC for the Russian group suggests the likely occurrence of nutritional deficiencies during pregnancy in Russia. However, the significant contribution of a country factor in the predictive model implies that the maternal serum trace-element concentrations explored in this study are incomplete indicators of fetal undernourishment.

Concentrations of essential trace elements in maternal serum and the effect on birth weight and newborn body mass index in sub-arctic and arctic populations of Norway and Russia

Concentrations of essential trace elements in maternal serum and the effect on birth weight and newborn body mass index in sub-arctic and arctic populations of Norway and Russia

Selective ligation of uterine artery branches accelerates fetal growth in the rat.

We determined if reducing litter number by selective fetal ablation (A) might enhance the growth of the surviving fetuses. On day 14 of the rat's 21.5-day gestation, we ligated branches of the uterine artery at their secondary division. Each of these branches supplies a placenta and its fetus, and ligation kills them. Every other fetus in litters of eight to 14 fetuses was ablated. Each A maternal rat was matched to a control with an equal number of fetuses. Ablation reduced fetal number (from 8-14 to 4-7) and increased fetal growth (birth weight 5.84 +/- 0.05 versus 5.20 +/- 0.05 g, p less than 0.001). In the A but not control litters, newborn body mass was negatively related to litter number. Fetuses of A litters had increased carcass, liver, and brain mass. On days 18 and 19, fetal plasma glucose concentrations, fetal/maternal glucose ratios, insulin concentrations, and hepatic glycogen concentrations were increased suggesting that A increases glucose provision to the surviving fetuses. Although these observations imply that A enhances glucose provision resulting in stimulated growth of insulin-sensitive tissues, the growth of the brain, purportedly a tissue not sensitive to insulin, was also increased. In addition, the growth rate of A fetuses continued to be increased on days 20 and 21 despite normal fetal plasma glucose and insulin. These observations indicate that with A, factors other than insulin also stimulated growth. Of note, newborn A pups developed hypoglycemia at 20 and 60 min as a result of increased insulin secretion.