11 pregnant women with protein malnutrition following biliopancreatic diversion for obesity were supported by parenteral nutrition (PN). In 2 cases high concentration glucose, lipid emulsions and standard aminoacid mixtures were infused via a central venous catheter; in the other subjects, because oral intake was normal or increased, only aminoacids with or without lipids were administered through a peripheral vein. PN promoted foetal growth and was very well tolerated and totally safe both for mother and infant.