Seasonal variations in weight of children attending an under-fives clinic in Lesotho.
The incidence of weight loss between successive visits, prevalence of under centile 3 weight-for-age and over centile 97, showed a marked bimodal annual variation for 1243 children attending an under-fives clinic. 9949 weighings on 661 boys and 682 girls over a five year period, contributed to the database. Season of birth also significantly influenced the centile distributions of weight-attained-for-age. Children over 1 1/2 years old showed considerably higher rates of weight loss (about 1 in 5 children attending in their fifth year of life), than children younger than the mean age of weaning. The rates of weight loss, together with seasonal variation, was considerably higher for a group of 'Regular Attenders' to the clinic, than for a group of 'Low Attenders'. Seasonal influences on growth need to be taken into accounts in evaluating the quality of care and outcome produced by under-fives clinics.