Growth and catch-up growth of Australian infants of low birthweight.

The growth of 90 infants of low birthweight (1500-2499 g) has been studied longitudinally from birth to 2 years of age. Seventy-five per cent of those infants were of birthweight that was appropriate-for-gestational age (AGA) and of mean gestational age 33.6 weeks (boys) and 34.5 weeks (girls). Twenty-four per cent were small-for-gestational age (SGA) and of mean gestational age 39.4 weeks (boys) and 38.5 weeks (girls). The data showed that, when gestational age was considered, the growth of AGA infants was similar to that of full-term infants of normal birthweight; SGA infants displayed accelerated growth ('catch-up'), particularly in the first months of life with upward percentile crossing from below the 5th toward the 50th. These results provide further evidence of the need to consider gestational age and whether AGA or SGA when assessing the growth of low birthweight infants.

The growth of healthy Australian infants in relation to infant feeding and social group.

A joint survey of infant-feeding practices and infant growth was carried out in Western Australia and Tasmania in 1984-1985. Birthweights and growth from birth to one year of age were similar in both States and to the international growth references. Infants who were never breast-fed or who were breast-fed for only a short time gained significantly more weight over the year (most of it after the age of three months) than did infants who were breast-fed for six months or longer. Infants from families of a lower socioeconomic group gained more weight after six months of age than did those infants from higher socioeconomic families. Analysis showed that the growth differences between the social groups was a result of differences in feeding practices. Linear growth was similar among infants of all social groups, irrespective of the feeding method.

Infant-feeding practices in Western Australia and Tasmania: a joint survey, 1984-1985.

A joint survey of infant-feeding practices that was carried out in Western Australia and Tasmania in 1984-1985 showed a continuing trend back to breast-feeding in both States. In Western Australia and Tasmania, 86% and 81% of mothers, respectively, were breast-feeding their babies on hospital discharge. Forty-five per cent of all mothers were still breast-feeding at six months. The social rank of the family had a significant effect on both the prevalence of breast-feeding and on the length of lactation: more mothers in the higher social groups breast-fed their infants, and for longer periods than did mothers of lower social groups. Few infants were introduced to solid foods before three months of age; however, solid and non-milk foods were introduced earlier to infants who were fed artificially than those who were breast-fed.

PIP: A survey of infant feeding practices in Western Australia and Tasmania carried out in 1984-85 confirms a trend toward a return to breastfeeding in both of these Australian states. Data from child health records on 911 infants from Western Australia and 460 infants in Tasmania were analyzed to a assess trends in infant feeding practices. At the time of discharge from the hospital, 84% of West Australian mothers and 77% of Tasmanian mothers were fully breastfeeding their infants. Breast milk continued to be the only source of milk for drinking at the age of 12 months for 11% of West Australian and 12% of Tasmanian infants. More mothers from the higher social groups breastfed their infants on discharge from the hospital than did mothers from lower social groups, and more of the higher socioeconomic status mothers continued to breastfeed throughout the 1st year of life. All mothers from the highest social group (A) in both states breastfed for at least 6 weeks, and 35% of such mothers in Western Australia and 50% in Tasmania were still breastfeeding at 12 months. In contrast, 65% of the West Australian and 50% of the Tasmanian mothers in the lowest socioeconomic strata (D) breastfed for 6 weeks, and only 9% of these mothers in Western Australia and 10% in Tasmania were still breastfeeding at 12 months. Few infants surveyed were introduced to solid foods before 3 months of age; however, solid and non-milk foods were introduced earlier to infants who were fed artificially than to those who were breastfed. Data from previous surveys indicate that the nadir of breastfeeding in Australia was reached in 1970. Since that time, women from the higher social groups have comprised the vanguard of the movement back to breastfeeding.

Pyloric stenosis in Western Australia, 1971-84.

Analyses of hospital records and census data for 1971-84 showed no significant increase in incidence of infantile hypertrophic pyloric stenosis in Western Australia. No link was found between breast feeding and incidence of disease. Low birth weight, short gestation pregnancies, and paternal family history of the disease were significant features.

Physical size of 1887 aboriginal schoolchildren in the Kimberley region.

This study has documented the weights and heights of 1887 Aboriginal schoolchildren from communities throughout the Kimberley region of Western Australia. The data have been analysed in relation to age and sex. Median weights and heights of the Aboriginal children approximated the 10th percentile for weight, and the 25th percentile for height of non-Aboriginal WA children. The data show that Aboriginal children who live in the more remote communities of the Kimberley region were smaller in weight and height than were those who lived in the towns. Retrospective data indicate that these differences between children from remote and town communities were present at their birth and through childhood. Median body mass indices (BMIs) approximated the 10th percentile values for BMI of non-Aboriginal children in the earlier years. The expected increase in BMI with age occurred later in Aboriginal children (at 11-12 years) than in non-Aboriginal children (eight years); in the older Aboriginal children (older than 11-12 years) median values approximated 25th percentile values of non-Aboriginal boys and 50th percentile values of non-Aboriginal girls of the same age.

Body size of young Australians aged five to 16 years.

In 1983-1984, 4578 Perth primary and secondary schoolchildren were studied. The selected sample was broadly representative of the ethnic groups that make up the Perth population and of the different social ranks within that population. The age, sex, weight, height, country of birth of the child and the parents, and occupation of the father were recorded for each subject. Weight, height and body mass index (BMI) increased with age. Age and sex were the most important determinants of body size. However, children of lower social rank and those with a southern European background were over-represented among the overweight children (greater than the 90th centile for BMI), particularly in adolescence. Children with an Asian background who were 11 years of age and younger were over-represented among the underweight children (less than or equal to the 10th centile for BMI). Results from this study indicate a continuing, though small (1.5 cm to 1.6 cm), secular increase in height over the past 13 to 14 years.

The Busselton children's survey, 1983. Body size from five to 16 years of age.

In 1983, 1623 primary and secondary schoolchildren took part in a health survey which was organized by the Busselton Population Studies Group. Age, sex, weight, height and country of birth were recorded for each child. Where possible, the country of birth of parents and the occupation of the father were extracted from previous Busselton surveys of adults. Compared with Perth schoolchildren, the difference in the attained weight and height of Busselton children at any age was small. This was so even though the two communities differ in location (rural compared with metropolitan), in ethnic origin (mainly British compared with diverse origins) and, probably, in social-rank distribution. Data from the two communities showed that a similar small secular increase in height had occurred since 1970/1971. This increase averaged at 1.2 cm for children at each year of age in Busselton and 1.5 cm to 1.6 cm for children in Perth.

The growth of breast fed and artificially fed infants from birth to twelve months.

Growth data collected from 394 healthy infants were analysed in relation to feeding practices. Infants were grouped on the basis of sex, if breast fed or artificially fed, and duration of breast feeding. From birth to 3 months, weight gains were similar for boys (2.5 kg) and also for girls (2.3 kg) irrespective of feeding method. From 3 to 6 months weight gains were greater in infants who were artificially fed from birth (2.0 kg both sexes) or breast fed for only a short time (1.9 kg) than for those exclusively breast fed for 6 months (1.6 kg) or longer (1.7 kg). Weight gains continued to be greater in artificially fed infants after 6 months. Over 12 months, artificially fed boys gained 410 g and girls 750 g more than those who were breast fed from birth. These differences occurred even though the artificial feedings that prevailed to 6 months and longer were low-solute ('humanized') formulas.

Australian longitudinal study of time and order of eruption of primary teeth.

Timing and sequence of eruption of primary teeth were studied longitudinally in 164 healthy Australian children. Eruption of primary teeth typically began between 7 and 8 months and was completed by 28 months. Tooth eruption was not significantly related to growth rate or to psychomotor maturity. Comparison of the eruption ages in this study with those from longitudinal studies in other countries suggests that no real changes in these have occurred over 40 yr despite increased affluence in industrialised countries over that period.

Growth and feeding practices of Western Australian infants.

Records from 12 metropolitan and six country Child Health Centres in Western Australia confirm a recent trend back to breast feeding; more than half the mothers were still breast feeding at three months. This trend was most marked and sustained in the highest socioeconomic group. Weight gains in infancy showed negative correlation with duration of breast feeding. By 12 months of age, infants from families in the lowest socioeconomic group, who breast-fed least, were significantly heavier than those from the highest. This fits our data which show an association between social class and breast feeding, and breast feeding and weight gain.

Breast feeding and growth of healthy infants.

Breast feeding was prevalent and sustained in a prospective growth study of healthy Perth infants and was accompanied by slower weight gains, compared to figures from the 1960s. This may have important effect on the future of young Australians.

The 1977 Busselton children's survey.

A health survey of 551 high school students in the coastal town of Busselton, Western Australia, was undertaken in November, 1977. Physical measurements showed that approximately 17% of the boys and 24% of the girls were overweight (115% or more of their standard weight for height and age). Blood pressures ranged from 108/64 mmHg at 13 years to 129/70 mmHg at 17 years for boys, and 109/63 mmHg to 116/66 mmHg for girls of the same age group. Fasting plasma glucose, cholesterol and triglyceride values were also obtained. Twenty-seven per cent of the girls and 17% of the boys were regular smokers, a habit often acquired by the age of 12 years. Most of the children watched television from two to four hours daily during the week, and for longer periods at weekends. Although most had satisfactory levels of physical fitness, there was a trend towards poor performance in overweight children, and there was a significant decrease in participation in regular sports by the older teenagers.

Nutrient consumption patterns of families in Busselton, Western Australia.

Nutrient consumption data were obtained from 211 members of 41 families living in the coastal town of Busselton, Western Australia. It was found that food consumption patterns were similar in boys and girls up to the age of 11 years. After that, as expected, males consumed more food than females. There was a general tendency for daily kilojoule intakes to be considerably less than the Australian Dietary Allowances for all age groups with the exception of males aged from 35 to 55 years. There was a significant prevalence of obesity in the subjects who were studied, particularly in the older groups of both sexes. The results suggest that, in the older adult groups, failure to make concessions to decreased levels of physical activity by modifying appetite and customary eating practices is a major factor which contributes to obesity.

Diet and serum cholesterol. An Australian family study.

Dietary intake patterns were studied in families in Busselton, Western Australia, known to have mothers and children with high, median, or low serum cholesterol values. There were no significant differences in the percentage contributions to total daily calories by protein, fat, or carbohydrate in mothers, children, or their families from these three groups. The results support the view that diet, per se, does not account for differences in observed serum cholesterol levels within a culturally homogeneous community.