Introduction: Racial and ethnic differences in fetal growth and birth size in the USA have not been adequately explained by individual-level socioeconomic status (SES) factors. We explored whether differences may be partially explained by county-level indicators of SES.
Methods: We linked participant zip codes from the National Institute of Child Health and Human Development Fetal Growth Studies (2009-2013; n=1614) to county-level US census data to calculate a neighbourhood deprivation index, education isolation index and two indices of segregation: racial isolation and evenness.
Background: Inadequate and excessive gestational weight gain (GWG) are associated with increased risk of newborn small- and large-for-gestational-age, respectively, and future offspring adiposity. However, the relationship between GWG and three-dimensional (3D) measures of fetal body composition and organ volumes, which may provide greater insight into fetal growth via measurement of soft tissue, remains unknown.
Objectives: The objective of this study was to examine the relationship between trimester-specific GWG and 3D fetal body composition and organ volume measurements.
The presence of a small spirocyclic ring at an adjacent position alters the conformational preference for equatorial substitution in six-membered rings. DFT calculations and low-temperature H NMR experiments demonstrate that alkyl groups larger than methyl possess negative A-values when geminal to a spirocyclopropane, with larger groups such as isopropyl and -butyl being exclusively axial at -78 °C. Similar effects are found for heteroatoms, including halogens, and for a range of other electron-withdrawing substituents.
View Article and Find Full Text PDFObjective: Gestational diabetes mellitus (GDM) increases the risk of fetal overgrowth as measured by two-dimensional ultrasonography. Whether fetal three-dimensional (3D) soft tissue and organ volumes provide additional insight into fetal overgrowth is unknown.
Research Design And Methods: We prospectively evaluated longitudinal 3D fetal body composition and organ volumes in a diverse U.
Background: Extreme in utero temperatures have been associated with adverse birth outcomes, including preterm birth and low birthweight. However, there is limited evidence on associations with neonatal intensive care unit (NICU) admissions, which reflect a range of poor neonatal health outcomes.
Methods: This case-crossover study assesses the associations between ambient temperature changes during the week of delivery and risk of NICU admission.