The intervention group will receive n-3 LC-PUFAs (DHA and EPA) as fish oil capsules from the 15th week of gestation until 4 months pp, the control group will get nutrition counselling according to the recommendations of the German Society for Nutrition during the same time period. Blood samples of the pregnant and lactating women, umbilical cord blood, placental tissue and blood of the newborns will be collected for fatty acid analysis.