The extract from rosemary contains carnosinic acid, which is a strong antioxidant. It does not contain the Rosemary aroma. The potential of rosemary to preserve food which contains lipids is known for a long time. Therefore rosemary is often added to fish, salami, salad oil and other food. 

Rosemary extract is a registered and safe food additive. It is extracted from natural rosemary. 

Information about pregnancy and rosemary, can be found here.