Effects of gestational age at birth on perinatal structural brain development in healthy term‐born babies

Abstract

Infants born in early term (37–38 weeks gestation) experience slower neurodevelopment than those born at full term (40–41 weeks gestation). While this could be due to higher perinatal morbidity, gestational age at birth may also have a direct effect on the brain. Here we characterise brain volume and white matter correlates of gestational age at birth in healthy term‐born neonates and their relationship to later neurodevelopmental outcome using T2 and diffusion weighted MRI acquired in the neonatal period from a cohort (n = 454) of healthy babies born at term age (>37 weeks gestation) and scanned between 1 and 41 days after birth. Images were analysed using tensor‐based morphometry and tract‐based spatial statistics. Neurodevelopment was assessed at age 18 months using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley‐III). Infants born earlier had higher relative ventricular volume and lower relative brain volume in the deep grey matter, cerebellum and brainstem. Earlier birth was also associated with lower fractional anisotropy, higher mean, axial, and radial diffusivity in major white matter tracts. Gestational age at birth was positively associated with all Bayley‐III subscales at age 18 months. Regression models predicting outcome from gestational age at birth were significantly improved after adding neuroimaging features associated with gestational age at birth. This work adds to the body of evidence of the impact of early term birth and highlights the importance of considering the effect of gestational age at birth in future neuroimaging studies including term‐born babies.

Harmonizing multisite neonatal diffusion-weighted brain MRI data for developmental neuroscience

“…This may represent altered white matter development at younger GA at birth within this sample of healthy term infants. In voxel-wise TBSS studies, lower FA and higher MD, AD and RD across the brain were associated with lower GA at birth (Broekman et al, 2014; Gale□Grant et al, 2022; Jin et al, 2019; Ou et al, 2017). Interestingly, we also identified a small region of the posterior/retrolenticular part of the left internal capsule where lower GA at birth was associated with higher FA.…”

“…GA at birth was chosen as birth earlier in the term period (e.g. 37-38 weeks) is associated with altered neonatal white matter development (Broekman et al, 2014a; Gale□Grant et al, 2022; Jin et al, 2019; Ou et al, 2017a) lower neurodevelopmental scores (Hua et al, 2019; Rose et al, 2013).…”

Association of early-term birth and breastfeeding practices with nutritional outcomes in singleton term infants: a multicenter cross-sectional study

“…This evidence of an association between early-term birth and adverse health outcomes in terms of growth and nutrition is intriguing. As we know, the evidence supporting the decision to advocate for deliveries at 39 weeks or later primarily arises from (1) the correlation between early-term births and increased risks of neonatal morbidity, mortality, hospitalization, and extended hospital stays [ 11 , 25 ] and (2) impaired long-term neurological development in early-term infants compared to full-term infants [ 26 ]. However, this evidence lacks confirmation of the association between early-term birth and adverse outcomes in children’s growth and nutrition.…”

Prenatal exposure to air pollution is associated with structural changes in the neonatal brain

“…There have been few studies analysing brain volumes in healthy term infants in the neonatal period ( Gale-Grant et al, 2022 ). However, in infants born preterm, increased ventricular volume ( Liverani et al, 2023 ) and decreased cGM volume ( Liverani et al, 2023 , Pagnozzi et al, 2023 ) in the neonatal period were associated with lower outcome scores at 2 years.…”