Fetal size vs growth: comparative analysis of three models of growth velocity based on third trimester estimated fetal weights for identifying stillbirth risk.
Antenatal surveillance
estimated fetal weight
fetal death
fetal growth restriction
growth deceleration
growth velocity
small for gestational age
stillbirth
Journal
American journal of obstetrics and gynecology
ISSN: 1097-6868
Titre abrégé: Am J Obstet Gynecol
Pays: United States
ID NLM: 0370476
Informations de publication
Date de publication:
25 Dec 2023
25 Dec 2023
Historique:
received:
14
10
2023
revised:
20
12
2023
accepted:
21
12
2023
medline:
28
12
2023
pubmed:
28
12
2023
entrez:
27
12
2023
Statut:
aheadofprint
Résumé
Fetal growth velocity is being recognised as an important parameter by which to monitor fetal wellbeing, in addition to assessment of fetal size. However there are different models and standards in use by which velocity is being assessed. We wanted to investigate three clinically applied methods of assessing growth velocity and their ability to identify stillbirth risk, in addition to that associated with small for gestational age. Retrospective analysis of prospectively recorded, routine-care data of pregnancies with 2 or more third trimester scans in New Zealand. Results of the last two scans were used for the analysis. The models investigated to define slow growth were A. 50+ centile drop between measurements, B. 30+ centile drop and C. estimated fetal weight below a projected optimal weight range, based on pre-defined, scan interval specific cut-offs to define normal growth. Each method's ability to identify stillbirth risk was assessed against that associated with small-for-gestational age at last scan. The study cohort consisted of 71,576 pregnancies. The last 2 scans in each pregnancy were performed at an average of 32+1 and 35+6 weeks gestation. The three models defined 'slow growth' at differing rates: A.: 50 centile drop 0.9%; B.: 30 centile drop 5.1%; C.: below projected optimal weight range 10.8%. Neither of the centile based models identified at-risk cases that were not also small for gestational age at last scan. The projected weight range method identified an additional 79% of non-SGA cases as slow growth, and these were associated with a significantly increased stillbirth risk (RR: 2.0; 95% CI: 1.2-3.4). Centile based methods fail to reflect adequacy of fetal weight gain at the extremes of the distribution. Guidelines endorsing such models might hinder the potential benefits of antenatal assessment of fetal growth velocity. A new, measurement-interval specific projection model of expected fetal weight gain can identify fetuses that are not small for gestational age, yet at risk of stillbirth because of slow growth. The velocity between scans can be calculated using a freely available growth rate calculator (www.perinatal.org.uk/growthrate).
Sections du résumé
BACKGROUND
BACKGROUND
Fetal growth velocity is being recognised as an important parameter by which to monitor fetal wellbeing, in addition to assessment of fetal size. However there are different models and standards in use by which velocity is being assessed.
OBJECTIVE
OBJECTIVE
We wanted to investigate three clinically applied methods of assessing growth velocity and their ability to identify stillbirth risk, in addition to that associated with small for gestational age.
STUDY DESIGN
METHODS
Retrospective analysis of prospectively recorded, routine-care data of pregnancies with 2 or more third trimester scans in New Zealand. Results of the last two scans were used for the analysis. The models investigated to define slow growth were A. 50+ centile drop between measurements, B. 30+ centile drop and C. estimated fetal weight below a projected optimal weight range, based on pre-defined, scan interval specific cut-offs to define normal growth. Each method's ability to identify stillbirth risk was assessed against that associated with small-for-gestational age at last scan.
RESULTS
RESULTS
The study cohort consisted of 71,576 pregnancies. The last 2 scans in each pregnancy were performed at an average of 32+1 and 35+6 weeks gestation. The three models defined 'slow growth' at differing rates: A.: 50 centile drop 0.9%; B.: 30 centile drop 5.1%; C.: below projected optimal weight range 10.8%. Neither of the centile based models identified at-risk cases that were not also small for gestational age at last scan. The projected weight range method identified an additional 79% of non-SGA cases as slow growth, and these were associated with a significantly increased stillbirth risk (RR: 2.0; 95% CI: 1.2-3.4).
CONCLUSIONS
CONCLUSIONS
Centile based methods fail to reflect adequacy of fetal weight gain at the extremes of the distribution. Guidelines endorsing such models might hinder the potential benefits of antenatal assessment of fetal growth velocity. A new, measurement-interval specific projection model of expected fetal weight gain can identify fetuses that are not small for gestational age, yet at risk of stillbirth because of slow growth. The velocity between scans can be calculated using a freely available growth rate calculator (www.perinatal.org.uk/growthrate).
Identifiants
pubmed: 38151221
pii: S0002-9378(23)02188-9
doi: 10.1016/j.ajog.2023.12.029
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Informations de copyright
Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.