Optimal risk assessment of small-for-gestational-age fetuses using 31-34-week biometry in a low-risk population.
Ultrasound Obstet Gynecol
; 43(3): 311-6, 2014 Mar.
Article
em En
| MEDLINE
| ID: mdl-24357451
ABSTRACT
OBJECTIVE:
To compare the performance of traditional growth charts for estimated fetal weight (EFW) and a validated pragmatic probabilistic approach using biometry at 31-34 weeks' gestation to screen for late pregnancy small-for-gestational age (SGA) fetuses in a low-risk population.METHODS:
Records of ultrasound biometry at 31-34 weeks were reviewed in 7755 consecutive low-risk women between 2002 and 2011. Fetal malformations, Doppler anomalies and preterm delivery before 37 weeks were excluded. SGA was defined by various percentile cut-offs of birth weight. The probability of SGA was modeled as a function of Z-scores of femur length, abdominal circumference and head circumference. The model was validated on a second independent dataset of 1725 pregnancies from a different screening unit. The screening performance of this probabilistic approach was compared with those of traditional EFW growth charts. The additional value of factoring in maternal characteristics was also ascertained.RESULTS:
Using national birth-weight charts, the proportions of newborns at 37-42 weeks with birth weight<3(rd) , <5(th) and<10(th) centiles were 3%, 6% and 12%, respectively, and there was a 2% rate of birth weight<2500 g. For a 10% false-positive rate, a direct probabilistic approach yielded a 51% detection rate of neonates with birth weight<10(th) centile, compared to the 32% and 48% detection rates given by the 10(th) centile cut-off of two reference charts for EFW. Adding maternal characteristics significantly improved detection rate by 2% to 53%.CONCLUSIONS:
The suggested validated approach to screening for late SGA fetuses outperforms traditional approaches using growth charts. By adding maternal characteristics, this screening method offers a favorable alternative to customized charts.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Recém-Nascido Pequeno para a Idade Gestacional
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Biometria
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Ultrassonografia Pré-Natal
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Retardo do Crescimento Fetal
Tipo de estudo:
Diagnostic_studies
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Etiology_studies
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Evaluation_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Adult
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Female
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Humans
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Newborn
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Pregnancy
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article