DOES THE ANTENATAL DETECTION OF SMALL-FOR-GESTATIONAL-AGE BABIES INFLUENCE THEIR TWO-YEAR OUTCOMES?

ABSTRACT

The aim of this paper is to determine whether antenatal detection of small-for-gestational-age (SGA) babies influences 2-year outcomes. All low-birth-weight (<2500g) infants born in South-East Thames region, England from September 1, 1992 to August 31, 1993 were identified at birth. Antenatal ``suspicion'' and ultrasound assessment confirming growth restriction was categorized as ``detection'' of SGA. Postnatally, infants were classified as SGA if they had a birth weight for given gestation below the 10th centile. At 2 years, those below 32 weeks' gestation and a random 25% sample of infants of 32 weeks' gestation or more underwent pediatric assessments. Of 49,787 births, 3456 (6.9%) were of low birth weight. One thousand four hundred and fifty one (42.5%) were SGA, of whom 611 (42%) were detected antenatally by ultrasound scan. At 2 years, 1008 (75.8%) of 1358 expected infants were assessed, 379 (37.6%) were SGA at birth, and 188 (49.6%) were confirmed antenatally. Although undetected infants had higher mean birth weights and gestational ages, they had a higher proportion of perinatal deaths (12.6 vs. 6.4%, RR 1.96: CI 1.32-2.86) than detected infants. At 2 years, detected SGA infants had smaller head circumferences (p = 0.026), a higher prevalence of febrile convulsions (8.0 vs. 3.1%: p = 0.040) and lower scores on the locomotor (DQA) scale of Griffith's developmental test (p = 0.021) compared with undetected SGA infants. Despite detected SGA fetuses having lower weights and gestation at birth than undetected fetuses, they had significantly lower mortality without a parallel increase in severe 2-year neuro-developmental, clinical, or growth morbidity.

KEYWORD

Postneonatal outcomes - antenatal detection - cohort study

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