Determining the interactions between psychological, nutritional and behavioral factors and their association with infant obesity risk in pregnancies with and without gestational diabetes mellitus.

Background/RationaleGestational diabetes mellitus (GDM) occurs in around 12% of Australian pregnancies. Infants born to mothers with GDM are often born large for gestational age (LGA) and suffer from adverse neonatal outcomes. Over their lifespan, these infants have a higher risks of obesity and metabolic disorders, than infants of mothers without GDM. The economic costs related to maternal GDM and obesity are up to 34% higher in the first year of life. Yet, modifiable risk factors such as maternal mental health, macronutrient intake, eating, (breast)feeding and sleeping behaviors which contribute to the early programming of infant metabolic health, remain understudied. Maternal mental health is poorer in women with GDM, as up to 26% of them suffer from perinatal depression, which is twice the frequency of women without GDM. Depression is associated with poorer eating behaviors and a higher intake of highly processed foods, which may lead to a 13% increase in the intake of calories and fat to reach the natural protein target. Maternal depression and anxiety also influence her towards a higher use of restrictive (breast)feeding behaviors with her infant and are associated with difficulties in breastfeeding, as well as with poorer sleep outcomes in the infant, which are in turn associated with obesity risk in infants. These maternal factors (mental health, nutrition, eating and (breast)feeding behaviors) may have important programming effects on the infant’s eating behaviors at birth and may be exacerbated in infants born to women with GDM, as pregnancies with GDM are characterized by higher glucose concentrations, which are shunted towards the fetus. The hypoglycemic episodes at birth, demonstrate a mismatch between the in utero and postpartum nutritional environment in infants. Furthermore, breastmilk quality is altered in mothers with previous GDM, and thus may further modify infant eating behaviors. Maternal mental health and GDM status may constitute two important predictors for the development of maladaptive nutrition and eating, sleeping behaviors in infants, which may in turn lead to higher anthropometric outcomes in infants and to a higher risk of obesity over the lifespan, which has been shown to be a growing problem in our society.Overall ObjectiveDetermining if modifiable risk factors (mental health, macronutrient intake, eating, (breast)feeding and sleeping behaviors) may be associated with higher anthropometric outcomes in infants born to pregnancies with and without depression, anxiety and GDM.Specific aims1) Determine the association between maternal mental health and GDM status and ; maternal and infant macronutrient intake, maternal and infant eating behaviors, maternal (breast)feeding behaviors and maternal and infant sleeping behaviors.2) Determine the association between maternal and infant macronutrient intake, maternal and infant eating behaviors, maternal (breast)feeding behaviors and maternal and infant sleeping behaviors and ; the infant’s anthropometry and investigate if this differs according to maternal mental health, GDM status and/or infant sex.MethodsBehaviors in the mother and the infant will be measured by self-reported questionnaires during pregnancy, at birth and at 6-8 weeks postpartum. Infant anthropometric outcomes (weight, length, fat and fat free mass) will be assessed at birth and at 6-8 weeks postpartum with validated and gold-standards instruments. Infant macronutrient intake will be measured at 6-8 weeks postpartum by analyzing the macronutrients present in maternal breastmilk. Maternal anthropometry (weigh and height) will be measured with scales during pregnancy, at birth and at 6-8 weeks postpartum.Expected results and their impactThis study will help to determine which modifiable risk factors are associated with a higher risk of infant obesity in populations with and without depression, anxiety and GDM. This will provide baseline data to inform the development of future comprehensive and tailored psychological and nutritional interventions to reduce the risk of obesity in infants and to reduce its related health and economic costs.