Neonatal and neurodevelopmental outcomes in preterm infants according to maternal body mass index: A prospective cohort study

Abstract

ObjectiveMaternal obesity is associated with an increase in maternal, foetal and neonatal morbidity and mortality. The aim of our study was to evaluate the relationships between maternal pre-pregnancy body mass index and (1) neonatal outcome in preterm infants, and (2) neurodevelopmental outcome at 2 years of corrected age.MethodWe conducted a single-centre cohort study. Infants born between 24+0 and 33+6 weeks of gestation between January 2009 and December 2013, hospitalised in the neonatal intensive care unit of Angers University Hospital, and with available data regarding maternal pre-pregnancy body mass index were eligible. Three groups were defined according to maternal body mass index: normal (n = 418), overweight (n = 136) and obese (n = 89). The primary outcome was neurodevelopment at 2 years of corrected age. Children with a non-optimal neuromotor and/or psychomotor assessment and/or a sensory disability were regarded as having a “non-optimal neurodevelopmental outcome”. Neuromotor function was regarded as non-optimal when cerebral palsy was present or when the clinical examination revealed neurological signs of abnormal muscular tone. Psychomotor assessment was regarded as non-optimal if the revised Brunet-Lézine test was < 85 or when the overall score in the parental Ages and Stages Questionnaire (ASQ) was < 185. Finally, sensory disabilities such as blindness and children who required a hearing aid were taken into account. The secondary outcome was the composite criteria of neonatal complications. Multivariable analysis included the following variables: mother’s age, gestational age, smoking during pregnancy, magnesium sulphate and steroid treatment during pregnancy, twin status, gender, socioeconomic status and social security benefits for those with low incomes.ResultsThe study population was composed of 643 preterm infants. Among them, 520 were assessed at 2 years. There was no difference in the proportion of infants with non-optimal neurodevelopmental outcomes between the three groups (16.6% for obese, 13.5% for overweight, 16.9% for normal body mass index mothers; p = 0.73). According to multivariable analysis, being born from an overweight or obese mother was not associated with an increased risk of non-optimal neuro-development at 2 years (adjusted OR = 0.84 [0.40–1.76] for obese, adjusted OR = 0.83 [0.43–1.59] for overweight mothers). There was no difference in the proportion of preterm infants with a non-optimal composite criterion of neonatal complications between the three groups. In the multivariable analysis, being born from an overweight or obese mother was not associated with an increased risk of non-optimal neonatal outcomes (adjusted OR = 0.95 [0.49–1.83] for obese, adjusted OR = 1.18 [0.69–2.01] for overweight mothers).ConclusionIn this large prospective cohort of preterm infants born before 34 weeks of gestation, we found no relationship between maternal body mass index and neurodevelopmental outcomes at 2 years of corrected age and no relationship between maternal body mass index an...

Early Growth and Cognitive Development in Children Born Preterm: Relevance of Maternal Body Mass Index

“…For instance, the evaluation at 2 years identified no association between maternal BMI, defined as discrete weight categories, and neurodevelopment in infants born prior to 34 weeks. 14 Also, the differences in definitions of early childhood development likely contribute to contrasting findings between our studies such as the use of combined outcomes to define “nonoptimal” development 14 as opposed to an exclusive focus on Bayley domain scores. We were not able to account for dietary intake during childhood in the postdischarge period.…”

“…We obtained self-reported maternal prepregnancy body weight and calculated BMI, which has been shown to be reliable and used in National Institutes of Health (NIH)-funded studies. 7 16 17 As prior investigations evaluate maternal BMI as overweight (25–25.9) or obese (≥30) for the comparison to children born to women with normal BMI (18.5–24.9), 10 14 we conceptualized maternal weight status dimensionally on the continuum of BMI. For this present study, electronic medical records of infants who survived to discharge ( n = 38) were reviewed to abstract growth and development during the first 3 years postdischarge.…”

“…8 9 10 11 However, some cohorts suggest no relationship between increasing maternal BMI and risk for motor or cognitive impairment. 12 13 14…”

Maternal glucose tolerance in pregnancy and child cognitive and behavioural problems in early and mid‐childhood

“…In the present study, we defined our main exposure as categories of maternal abnormal glucose tolerance during pregnancy (GDM, IGT, IH) compared with NGT. We also investigated glucose as a con- 42,43 Finally, in Model 3 we additionally adjusted for maternal general IQ. We assessed potential effect modification by examining models stratified by sex and computed sex by abnormal glucose tolerance interaction P-values.…”

“…Model 1 was an unadjusted model that estimated mean differences in cognition scores and behaviour scores according to maternal abnormal glucose tolerance categories, with NGT as the reference category. For Model 2, we adjusted for maternal race/ethnicity, pre‐pregnancy BMI, age, parity, smoking status, education, and household income at enrolment, in addition to child's sex and age, which were associated with the outcomes or exposures or were considered important potential confounders based on previous literature 42,43 . Finally, in Model 3 we additionally adjusted for maternal general IQ.…”