Scientific Concepts


birefringence birefringence measurements birth birth-weight infants birth asphyxia birth centres birth certificate data birth certificates birth cohort birth cohort analysis	birth cohort effects birth cohort studies birth cohort study birth complications birth control birth control pills birth data birth date birth defect birth defects birth experience	birth hospital birth length birth mass birth month birth mothers birth order birth outcomes birth peak birth prevalence birth process birth rate	birth records birth season birth seasonality birth sex ratio birth size birth trauma birth weight birth weight infants birth year birthday birthing experience	birthing position birthweight birthweight centiles birthweight children birthweight difference