TY - JOUR

T1 - Association between perinatal mortality and morbidity and customised and non-customised birthweight centiles in Denmark, Finland, Norway, Wales, and England

T2 - comparative, population based, record linkage study

AU - Kilpi, Fanny

AU - Jones, Hayley E

AU - Magnus, Maria Christine

AU - Santorelli, Gillian

AU - Højsgaard Schmidt, Lise Kristine

AU - Urhoj, Stine Kjaer

AU - Nelson, Scott M

AU - Tuffnell, Derek

AU - French, Robert

AU - Magnus, Per Minor

AU - Nybo Andersen, Anne-Marie

AU - Martikainen, Pekka

AU - Tilling, Kate

AU - Lawlor, Deborah A

N1 - © Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.

PY - 2023

Y1 - 2023

N2 - OBJECTIVES: To compare the risk of adverse perinatal outcomes according to infants who are born small for gestational age (SGA; <10th centile) or large for gestational age (LGA; >90th centile), as defined by birthweight centiles that are non-customised (ie, standardised by sex and gestational age only) and customised (by sex, gestational age, maternal weight, height, parity, and ethnic group).DESIGN: Comparative, population based, record linkage study with meta-analysis of results.SETTING: Denmark, Finland, Norway, Wales, and England (city of Bradford), 1986-2019.PARTICIPANTS: 2 129 782 infants born at term in birth registries.MAIN OUTCOME MEASURES: Stillbirth, neonatal death, infant death, admission to neonatal intensive care unit, and low Apgar score (<7) at 5 minutes.RESULTS: Relative to those infants born average for gestational age (AGA), both SGA and LGA births were at increased risk of all five outcomes, but observed relative risks were similar irrespective of whether non-customised or customised charts were used. For example, for SGA versus AGA births, when non-customised and customised charts were used, relative risks pooled over countries were 3.60 (95% confidence interval 3.29 to 3.93) versus 3.58 (3.02 to 4.24) for stillbirth, 2.83 (2.18 to 3.67) versus 3.32 (2.05 to 5.36) for neonatal death, 2.82 (2.07 to 3.83) versus 3.17 (2.20 to 4.56) for infant death, 1.66 (1.49 to 1.86) versus 1.54 (1.30 to 1.81) for low Apgar score at 5 minutes, and (based on Bradford data only) 1.97 (1.74 to 2.22) versus 1.94 (1.70 to 2.21) for admission to the neonatal intensive care unit. The estimated sensitivity of combined SGA or LGA births to identify the three mortality outcomes ranged from 31% to 34% for non-customised charts and from 34% to 38% for customised charts, with a specificity of 82% and 80% with non-customised and customised charts, respectively.CONCLUSIONS: These results suggest an increased risk of adverse perinatal outcomes of a similar magnitude among SGA or LGA term infants when customised and non-customised centiles are used. Use of customised charts for SGA/LGA births-over and above use of non-customised charts for SGA/LGA births-is unlikely to provide benefits in terms of identifying term births at risk of these outcomes.

AB - OBJECTIVES: To compare the risk of adverse perinatal outcomes according to infants who are born small for gestational age (SGA; <10th centile) or large for gestational age (LGA; >90th centile), as defined by birthweight centiles that are non-customised (ie, standardised by sex and gestational age only) and customised (by sex, gestational age, maternal weight, height, parity, and ethnic group).DESIGN: Comparative, population based, record linkage study with meta-analysis of results.SETTING: Denmark, Finland, Norway, Wales, and England (city of Bradford), 1986-2019.PARTICIPANTS: 2 129 782 infants born at term in birth registries.MAIN OUTCOME MEASURES: Stillbirth, neonatal death, infant death, admission to neonatal intensive care unit, and low Apgar score (<7) at 5 minutes.RESULTS: Relative to those infants born average for gestational age (AGA), both SGA and LGA births were at increased risk of all five outcomes, but observed relative risks were similar irrespective of whether non-customised or customised charts were used. For example, for SGA versus AGA births, when non-customised and customised charts were used, relative risks pooled over countries were 3.60 (95% confidence interval 3.29 to 3.93) versus 3.58 (3.02 to 4.24) for stillbirth, 2.83 (2.18 to 3.67) versus 3.32 (2.05 to 5.36) for neonatal death, 2.82 (2.07 to 3.83) versus 3.17 (2.20 to 4.56) for infant death, 1.66 (1.49 to 1.86) versus 1.54 (1.30 to 1.81) for low Apgar score at 5 minutes, and (based on Bradford data only) 1.97 (1.74 to 2.22) versus 1.94 (1.70 to 2.21) for admission to the neonatal intensive care unit. The estimated sensitivity of combined SGA or LGA births to identify the three mortality outcomes ranged from 31% to 34% for non-customised charts and from 34% to 38% for customised charts, with a specificity of 82% and 80% with non-customised and customised charts, respectively.CONCLUSIONS: These results suggest an increased risk of adverse perinatal outcomes of a similar magnitude among SGA or LGA term infants when customised and non-customised centiles are used. Use of customised charts for SGA/LGA births-over and above use of non-customised charts for SGA/LGA births-is unlikely to provide benefits in terms of identifying term births at risk of these outcomes.

U2 - 10.1136/bmjmed-2023-000521

DO - 10.1136/bmjmed-2023-000521

M3 - Journal article

C2 - 37663045

VL - 2

JO - BMJ medicine

JF - BMJ medicine

SN - 2754-0413

IS - 1

M1 - e000521

ER -