Maternal obesity, diabetes mellitus and cord blood biomarkers in large-for-gestational age infants

Association of parental prepregnancy BMI with neonatal outcomes and birth defect in fresh embryo transfer cycles: a retrospective cohort study

Background

Parental body mass index (BMI) is associated with pregnancy outcomes. But the effect of parental prepregnancy BMI on offspring conceived via in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI), especially the birth defect, remains to be determined. This study aimed to investigate the associations of parental prepregnancy BMI with neonatal outcomes and birth defect in fresh embryo transfer cycles.

Methods

We conducted a retrospective cohort study including 5741 couples in their first fresh IVF/ICSI cycles admitted to Women’s Hospital, School of Medicine, Zhejiang University from January 2013 to July 2016. The primary outcome was birth defects, which was classified according to the International Classification of Diseases, 10th Revision. Secondary outcomes included preterm delivery rate, infant gender, birth weight, small-for-gestational age (SGA) and large-for-gestational age (LGA). Multilevel regression analyses were used to assess the associations of parental prepregnancy BMI with neonatal outcomes and birth defect.

Results

In singletons, couples with prepregnancy BMI ≥25 kg/m² had higher odds of LGA than those with BMI < 25 kg/m². The birth defect rate was significantly higher when paternal prepregnancy BMI ≥25 kg/m² in IVF cycles (aOR 1.82, 95% CI 1.06–3.10) and maternal BMI ≥25 kg/m² in ICSI cycles (aOR 4.89, 95% CI 1.45–16.53). For subcategories of birth defects, only the odds of congenital malformations of musculoskeletal system was significantly increased in IVF offspring with paternal BMI ≥25 kg/m² (aOR 4.55, 95% CI 1.32–15.71). For twins, there was no significant difference among four groups, except for the lower birth weight of IVF female infants.

Conclusions

Parental prepregnancy BMI ≥25 kg/m² is associated with higher incidence of LGA in IVF/ICSI singletons. Paternal prepregnancy BMI ≥25 kg/m² was likely to have higher risk of birth defect in IVF offspring than those with BMI < 25 kg/m², particularly in the musculoskeletal system. It is essential for overweight or obesity couples to lose weight before IVF/ICSI treatments.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04261-y.

Association of maternal pre-pregnancy low or increased body mass index with adverse pregnancy outcomes

This study investigated the association between pre-pregnancy body mass index (BMI) and adverse pregnancy outcomes among women participated in the National Free Preconception Health Examination Project in Guangdong Province, China, and explored these associations according to maternal age. Pre-pregnancy BMI was classified into underweight (BMI < 18.5 kg/m²), healthy weight (18.5–23.9 kg/m²), overweight (24.0–27.9 kg/m²), and obesity (≥ 28.0 kg/m²) according to Chinese criteria. Outcomes were preterm birth (PTB, delivery before 37 weeks of gestation), large for gestational age (LGA, birthweight above the 90th percentile for gestational age by infants’ sex), small for gestational age (SGA, birthweight below the 10th percentile for gestational age by infants’ sex), primary caesarean delivery, shoulder dystocia or birth injury, and stillbirth. Adjusted incidence risk ratios (aIRR) were calculated for underweight, overweight and obesity, respectively. Compared with healthy weight, underweight was associated with increased risk of PTB (aIRR 1.06, 95%CI 1.04–1.09) and SGA (1.23, 1.22–1.26) but inversely associated with LGA (0.83, 0.82–0.85), primary caesarean delivery (0.88, 0.87–0.90) and stillbirth (0.73, 0.53–0.99). Overweight was associated with increased risk of LGA (1.17, 1.14–1.19), primary caesarean delivery (1.18, 1.16–1.20) and stillbirth (1.44, 1.03–2.06), but inversely associated with SGA (0.92, 0.90–0.95) and shoulder dystocia or birth injury (0.86, 0.79–0.93). Obesity was associated with increased risk of PTB (1.12, 1.05–1.20), LGA (1.32, 1.27–1.37), primary caesarean delivery (1.45, 1.40–1.50), but inversely associated with SGA (0.92, 0.87–0.97). The aIRRs for underweight, overweight and obesity in relation to these adverse pregnancy outcomes ranged from 0.65 to 1.52 according to maternal age. In Chinese population, maternal pre-pregnancy BMI was significantly associated with the risk of adverse pregnancy outcomes and the risk differs according to maternal age. Further investigation is warranted to determine whether and how counselling and interventions for women with low or increased BMI before pregnancy can reduce the risk of adverse pregnancy outcomes.

Intergenerational transmission of the effects of maternal exposure to childhood maltreatment on offspring obesity risk: A fetal programming perspective

Childhood obesity constitutes a major global public health challenge. A substantial body of evidence suggests that conditions and states experienced by the embryo/fetus in utero can result in structural and functional changes in cells, tissues, organ systems and homeostatic set points related to obesity. Furthermore, growing evidence suggests that maternal conditions and states experienced prior to conception, such as stress, obesity and metabolic dysfunction, may spill over into pregnancy and influence those key aspects of gestational biology that program offspring obesity risk. In this narrative review, we advance a novel hypothesis and life-span framework to propose that maternal exposure to childhood maltreatment may constitute an important and as-yet-underappreciated risk factor implicated in developmental programming of offspring obesity risk via the long-term psychological, biological and behavioral sequelae of childhood maltreatment exposure. In this context, our framework considers the key role of maternal-placental-fetal endocrine, immune and metabolic pathways and also other processes including epigenetics, oocyte mitochondrial biology, and the maternal and infant microbiomes. Finally, our paper discusses future research directions required to elucidate the nature and mechanisms of the intergenerational transmission of the effects of maternal childhood maltreatment on offspring obesity risk.

Biomarkers for Macrosomia Prediction in Pregnancies Affected by Diabetes

Large birthweight, or macrosomia, is one of the commonest complications for pregnancies affected by diabetes. As macrosomia is associated with an increased risk of a number of adverse outcomes for both the mother and offspring, accurate antenatal prediction of fetal macrosomia could be beneficial in guiding appropriate models of care and interventions that may avoid or reduce these associated risks. However, current prediction strategies which include physical examination and ultrasound assessment, are imprecise. Biomarkers are proving useful in various specialties and may offer a new avenue for improved prediction of macrosomia. Prime biomarker candidates in pregnancies with diabetes include maternal glycaemic markers (glucose, 1,5-anhydroglucitol, glycosylated hemoglobin) and hormones proposed implicated in placental nutrient transfer (adiponectin and insulin-like growth factor-1). There is some support for an association of these biomarkers with birthweight and/or macrosomia, although current evidence in this emerging field is still limited. Thus, although biomarkers hold promise, further investigation is needed to elucidate the potential clinical utility of biomarkers for macrosomia prediction for pregnancies affected by diabetes.

Maternal Obesity Affects Inflammatory and Iron Indices in Umbilical Cord Blood

OBJECTIVE

To determine the impact of maternal obesity and gestational weight gain across pregnancy on fetal indices of inflammation and iron status.

STUDY DESIGN

Eighty-five healthy term newborns delivered via elective cesarean were categorized by 2 maternal body mass index (BMI) thresholds; above or below 30 kg/m(2) or above or below 35 kg/m(2). Umbilical cord plasma levels of C-reactive protein, interleukin (IL)-6, tumor necrosis factor (TNF)-α, ferritin, and hepcidin were assayed. Cytokines released by phytohemagglutinin-stimulated umbilical cord mononuclear cells (MNCs) were assayed.

RESULTS

Maternal class II obesity, defined as BMI of 35 kg/m(2) and above, predicted higher C-reactive protein and TNF-α in umbilical cord plasma (P < .05 for both), and also proinflammatory cytokines (IL-1β, IL-6, and TNF-α) from stimulated MNC (P < .05 for all). The rise in plasma TNF-α and MNC TNF-α was not linear but occurred when the threshold of BMI 35 kg/m(2) was reached (P < .005, P < .06). Poorer umbilical cord iron indices were associated with maternal obesity. When ferritin was low, IL-6 was higher (P < .04), but this relationship was present primarily when maternal BMI exceeded 35 kg/m(2) (P < .03). Ferritin was correlated with hepcidin (P < .0001), but hepcidin was unrelated to either maternal BMI or inflammatory indices.

CONCLUSIONS

Class II obesity and above during pregnancy is associated with fetal inflammation in a threshold fashion. Although maternal BMI negatively impacted fetal iron status, hepcidin, related to obesity in adults, was related to iron status and not obesity in fetuses. Pediatricians should be aware of these relationships.

Macrosomia in non-gestational diabetes pregnancy: glucose tolerance test characteristics and feto-maternal complications in tropical Asia Pacific Australia

OBJECTIVE

To look into the glucose tolerance test characteristics and determine complications in non-gestational diabetes pregnant subjects.

METHODS

From 2006 to 2009 all non-gestational diabetes mellitus (non-GDM) pregnant women who delivered macrosomia at the North Australia's Townsville Hospital were retrospectively reviewed by extracting data from clinical record. Glucose tolerance tests results were analysed in the light of an earlier diagnosis of non-GDM.

RESULTS

Ninety-one non-GDM mothers with macrosomia were studied and compared with 41 normoglycemic subjects without macrosomia. Of the subjects with non-GDM macrosomia, 45 (49.4%) had normal 50 g glucose challenge test (GCT) without further testing, another 8 (8.8%) had abnormal GCT but normal 75 g oral glucose tolerance test (OGTT). A total of 4 (4.4%) subjects had normal GCT and OGTT. Interestingly, 14 out of 16 (87.5%) subjects who were tested with OGTT owing to past history of macrosomia had normal results but delivered macrosomic babies. Only 12 subjects had both GCT and OGTT, the rest of the cohort had either of the two tests. Subjects with non-GDM macrosomia had higher frequency of neonatal hypoglycaemia 34% as compared to 10% in non-macrosomic babies (P=0.003). Other feto-maternal complications were similar in both groups.

CONCLUSIONS

No significant pattern of glucose tolerance characteristics was identified in non-GDM mothers with macrosomic babies. In spite of being normoglycemic significant neonatal hypoglycaemia was recorded in non-GDM macrosomic babies. Further prospective studies on a larger population are needed to verify our findings.

Neutralizing Th2 inflammation in neonatal islets prevents β-cell failure in adult IUGR rats

Intrauterine growth restriction (IUGR) leads to development of type 2 diabetes (T2D) in adulthood. The mechanisms underlying this phenomenon have not been fully elucidated. Inflammation is associated with T2D; however, it is unknown whether inflammation is causal or secondary to the altered metabolic state. Here we show that the mechanism by which IUGR leads to the development of T2D in adulthood is via transient recruitment of T-helper 2 (Th) lymphocytes and macrophages in fetal islets resulting in localized inflammation. Although this immune response is short-lived, it results in a permanent reduction in islet vascularity and impaired insulin secretion. Neutralizing interleukin-4 antibody therapy given only in the newborn period ameliorates inflammation and restores vascularity and β-cell function into adulthood, demonstrating a novel role for Th2 immune responses in the induction and progression of T2D. In the neonatal stage, inflammation and vascular changes are reversible and may define an important developmental window for therapeutic intervention to prevent adult-onset diabetes.