The detection of early weight faltering at the 6-8-week check and its association with family factors, feeding and behavioural development.

AIMS: To identify infants with early weight faltering at the 6-8-week check and examine their family circumstances, feeding and behavioural development.
METHODS: Over a 2-year period, the weight gain of all infants born in an area of North East England was screened. z Scores for weights at birth and at 6-8 weeks were used to calculate a "thrive index" (z score for weight gain). In a nested case-control study within the larger cohort, infants below the fifth centile on the thrive index were identified. 74 cases and 86 controls were followed up. Their development was assessed at 4 and 9 months using the Bayley Scales and their mothers interviewed.
RESULTS: Of 1996 infants, weights at birth and at 6-8 weeks were available for 1880 (94%), and 6.1% of term-born infants were identified as weight faltering over the first 6-8 weeks. These infants had more feeding problems and showed some developmental delay as assessed using the Bayley Scales (at 4 months, mean difference and 95% CI -3.5, -0.6 to -6.4 for the Mental Developmental Index (MDI) and -3.6, -0.2 to - 6.9 for the Psychomotor Developmental Index (PDI); at 9 months -2.3, 1.3 to -5.8 for MDI and -2.2, 2.5 to -7.0 for PDI). Their families were not significantly different from those of controls on any economic or educational measure.
CONCLUSION: Infants whose early weight gain is slow show more feeding problems than controls, and some developmental delay. They can be identified using a thrive index at the 6-8-week check.