Iron poisoning in young children: association with the birth of a sibling.

BACKGROUND Iron is a leading cause of death due to poisoning in young children. Because perinatal iron therapy is common, the presence of these tablets, which have a candylike appearence, in the home may pose a hazard to a mother's other young children. We explored the association between iron poisoning in young children and the birth of a sibling. METHODS We conducted a population-based case-control study linking health care databases in Ontario. Health care records for the mothers of children less than 3 years of age admitted to hospital with iron poisoning between Apr. 1, 1991, and Mar. 31, 2000, were compared with those for the mothers of age- and sex-matched control children without iron poisoning. RESULTS We studied records for 40 children admitted to hospital for iron poisoning. Seventeen cases (42%) occurred within a year (before or after) a sibling's birth. Children whose mothers had given birth to a sibling were almost twice as likely as children whose mothers had not given birth to a sibling to be admitted for iron poisoning within 6 months of birth (adjusted odds ratio [OR] 1.9, 95% confidence interval [CI] 0.9 to 3.9). The postpartum year was associated with a consistently elevated risk, including an almost 4-fold increase in the risk of iron poisoning during the first postpartum month (adjusted OR 3.6, 95% CI 0.8 to 16.5). INTERPRETATION Pregnancy is a major risk factor for iron poisoning in young children, and the period immediately after delivery is associated with the greatest risk. Almost half of all hospital admissions for iron poisoning in young children could be prevented by keeping iron supplements safely out of reach in the year before and after the birth of a sibling.