tThis study evaluated the effect of supplemental vitamin E to ewes in late pregnancy on therate of stillborn lambs. Ewes in 19 flocks in 5 regions of Norway were daily supplementedthe 6–7 weeks before average expected lambing date with either (1) 360 IU of vitamin E(supplemented), or (2) placebo (control). The daily supplement was given in addition to the daily basal diet of forage, concentrate and mixture of minerals and vitamins in each flock,assuming that forage contained on average 40 mg -tocopherol/kg DM. Information aboutthe basal diets was collected via analyses of forage samples and questionnaires. Blood wascollected from a sample of ewes in each flock 1 week pre-treatment (7–8 weeks beforelambing), and from some flocks 1–2 weeks after initiation of supplementation (5–6 weeksbefore lambing) and 1–2 weeks after lambing. The body condition score (BCS) of the eweswas assessed 4–6 weeks before lambing. Mean content (±SD) of -tocopherol in the forageof the 19 flocks was 25 ± 17 mg/kg DM. Mean daily intake of vitamin E of the ewes fromthe basal diet was 153 ± 44 IU. Vitamin E supplementation increased serum concentrationof -tocopherol (P = 0.0002) 5–6 weeks before lambing. After lambing there was a higher ratio of -tocopherol to cholesterol in serum of supplemented ewes compared with controlewes (P = 0.02). Ewes with one or more stillborn lambs had lower serum -tocopherol concentrations than ewes without stillborn lambs in litters with ≥3 lambs (P = 0.01). Forewes with ≥3 lambs there was a significant lower stillbirth rate for vitamin E supplementedthan for control ewes (P = 0.0004), while there was no effect on the stillbirth rate for eweshaving ≤2 lambs. Ewes with low BCS had a higher stillbirth rate than ewes with medium orhigh BCS (P = 0.001). The results of this study indicate that daily supplementation of vitaminE during the last 6–7 weeks before lambing decreases the stillbirth rate of ewes having ≥3lambs