RT Journal Article SR Electronic T1 O-086 Infections And The Duration Of Full Or Partial Breastfeeding; The Norwegian Mother And Child Cohort Study (moba) JF Archives of Disease in Childhood JO Arch Dis Child FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP A57 OP A58 DO 10.1136/archdischild-2014-307384.154 VO 99 IS Suppl 2 A1 Stordal, K A1 Lundeby, KM A1 Brantsæter, AL A1 Haugen, M A1 Lund-Blix, NA YR 2014 UL http://adc.bmj.com/content/99/Suppl_2/A57.2.abstract AB Background and aims Breastmilk contains factors important for immunity. However, the benefit of prolonged full breastfeeding for 4 compared to 6 months as infection prevention in an affluent society is unclear. Methods In a prospective birth cohort study recruiting from 1999–2008, questionnaires were completed at 6 and 18 months of age regarding infant diet and the occurrence and hospitalisation for infections. The study sample included 67 856 children (50.9% girls). Results After adjustments for maternal age, parity, sectio delivery, smoking, gender, birthweight, gestational age and daycare, hospitalisation for infections was similar for infants fully breastfed for 6 (14%, reference category) vs 4 (41%) months (adjusted OR 0.88, 95% CI 0.77–1.00) but increased for never breastfed (aOR 1.41, 0.99–2.00) or partially breastfed <4 months (aOR 1.25, 1.06–1.47). Gastroenteritis was associated with no breastfeeding (aOR 1.77, 1.42–2.21), partial breastfeeding < 4 months (aOR 1.90, 1.72–2.09) or 4–6 months (aOR 1.33, 1.22–1.45). From 6 to 18 months the risk of hospitalisation for infection was higher for those who stopped any breastfeeding < 4 months (aOR 1.40, 1.25–1.57), 4–6 (aOR 1.29, 1.13–1.49) and for 6–8 months (aOR 1.11, 1.00–1.24), whereas similar risk was observed for breastfeeding 9–11 compared to breastfeeding ≥12 months. Conclusions Full breastfeeding for 6 months was associated with a reduction in hospitalisation for infections compared with absent or partial breastfeeding from <4 months, but not compared to full breastfeeding for 4 months. Reduced risk of hospitalisation was found with any breastfeeding up to 9 months’ age but not beyond.