Factors associated with size and proportionality at birth in term Jamaican infants.

The objective of this study was to identify the factors associated with size and proportionality at birth in a cohort of term infants established to investigate their growth and development. One hundred and forty term low-birth-weight (birth-weight < 2,500 g) infants and 94 normal birth-weight infants (2,500- < 4,000 g) were recruited within 48 hours of birth at the main maternity hospital, Kingston, Jamaica. Birth anthropometry and gestational age were measured, and maternal information was obtained by interview and from hospital records. Controlling for gestational age, variables independently associated with birth-weight were rate of weight gain in the second half of pregnancy, maternal height, haemoglobin level < 9.5 microg/dL, time of first attendance in antenatal clinic, birth order, pre-eclampsia, and consumption of alcohol, with 33% of the variance in birth-weight explained. Birth length was associated only with maternal height and age, while measures of proportionality (ponderal index and head/length ratio) were associated with characteristics of the environment in late pregnancy, including rate of weight gain, weight in late pregnancy, and pre-eclampsia. The variation in maternal characteristics associated with size or proportionality at birth may reflect the times during gestation when different aspects of growth are most affected.

The nutritional status of rural Jamaican school children

Three thousand, eight hundred and eighty-two (3,882) children in grades 2-5, attending 16 rural primary and all-age schools in central Jamaica were weighed and their weight-for-age standard deviation scores calculated using the World Health Organization/National Center for Health Statistics (WHO/NCHS) references. Heights were also measured in a random sample of the grade 5 children (n = 793) and height-for-age and body mass index (BMI-kg/m2) calculated. Sixty-nine per cent of the total sample were of normal weight-for-age, 2were moderately undernourished (weight-for-age > -3 Z-score, -2 Z-score, < or = -1 Z-score). Few children were overweight. The frequency distribution of weight-for-age was similar in girls and boys. In the subsample of children in whom heights were measured, 25.8were < or = -1 Z-score height-for-age, and of these 4.9were < -2 Z-score. Compared with a survey conducted in a similar rural area in the 1960s, the children's mean weights for age group categories were 1.1 to 3.7 kg heavier. Children who were older than appropriate for their grade were more likely to be undernourished (Odds ratio 3.94, 95CI 3.21, 4.83), which suggests that undernourished children may be more likely to repeat a grade or start school later.