ORIGINAL ARTICLE Breast feeding and the sudden infant death syndrome in Scandinavia, 1992–95

Aims: To assess the effects of breast feeding habits on sudden infant death syndrome (SIDS). Methods: The analyses are based on data from the Nordic Epidemiological SIDS Study, a case–control study in which parents of SIDS victims in the Scandinavian countries between 1 Septem-ber 1992 and 31 August 1995 were invited to participate, each with parents of four matched controls. The odds ratios presented were computed by conditional logistic regression analysis. Results: After adjustment for smoking during pregnancy, paternal employment, sleeping position, and age of the infant, the adjusted odds ratio (95 % CI) was 5.1 (2.3 to 11.2) if the infant was exclusively breast fed for less than four weeks, 3.7 (1.6 to 8.4) for 4–7 weeks, 1.6 (0.7 to 3.6) for 8–11 weeks, and 2.8 (1.2 to 6.8) for 12–15 weeks, with exclusive breast feeding over 16 weeks as the reference. Mixed feeding in the first week post partum did not increase the risk. Conclusions: The study is supportive of a weak relation between breast feeding and SIDS reduction. It is commonly observed that the prevalence of bottle feedingis higher among cases of sudden infant death syndrome(SIDS) than among controls.1–4 However, Siwe in Sweden5 and others6 7 did not find any difference. There is still contro-versy as to whether bottle feeding is an independent risk fac-tor or not. In Copenhagen, Biering-Sørensen and colleagues