Abstracts

Asthma, a leading cause of early childhood hospital admissions, is increasing in prevalence in many countries. The conclusions of this Australian study, which showed a significant risk reduction of childhood asthma at the age of six years when breastfeeding is continued for at least the first 4 months after birth,s is that public health interventions to optimize breastfeeding may help to reduce the "community burden" of childhood asthma and its associated problems.

The authors followed 2187 children from antenatal clinics in Perth, Australia, and measured the duration of exclusive breastfeeding and outcomes related to asthma and atopy at the age of 6 years. After eliminating confounding factors such as sex, gestational age, smoking of parent and early child care, they determined that the introduction of milk other than breastmilk before 4 months of age was a significant risk factor for all forms of asthma and atopy in 6 year olds. The protective mechanism, they suggest is the exclusion of milk other than breastmilk because of its potentially allergenic components, and the provision of immunomodulatory, anti-inflammatory, nutritional or other components in human milk. The findings suggest that the age of introduction rather than the duration of exclusive breastfeeding determined the close association between asthma and atopy at age 6, but as these two variables are highly correlated, the role of breastfeeding itself is of prime importance.

The purpose of this Swedish longitudinal study was to determine the impact of thumb sucking and pacifier use on exclusive breastfeeding and on the overall duration of breastfeeding as part of a WHO collaborative project to research breastfeeding practices and lactational amenorrhoea.

The subjects consisted of 506 mother and infant pairs. The mothers were instructed to record infant feeding patterns daily from the first week after delivery until the second menstruation postpartum or a new pregnancy and were visited by a research assistant every two weeks.

Thumb sucking started early and at two weeks the prevalence was 61 per cent and at 16 weeks was up to 91 per cent. During the first 6 months, 2 per cent of infants did not thumb suck.

Pacifier use was initiated early. During the first week 60 per cent of infants were offered pacifiers. This increased by 12 per cent during the second week and another 6 per cent during the 3rd week. Fifteen per cent of infants did not use pacifiers.

The study confirms earlier research that pacifiers have a negative impact on breastfeeding patterns. Pacifier use in this study was related to fewer feeds per 24 hours, shorter suckling duration, shorter duration of exclusive breastfeeding and shorter total duration of breastfeeding. No such relationship was associated with thumb sucking. They conclude that thumb sucking did not negatively effect breastfeeding patterns. The negative effects of pacifiers were related to the frequency of their use. The occasional use of pacifiers did not have a negative effect.