North American serum, typically referring to North American Fetal Bovine Serum (FBS), is a type of serum derived from fetal cows in North America, such as the United States and Canada. It is commonly used in cell culture to provide essential nutrients, growth factors, and hormones that support cell growth and maintenance. North American FBS is widely used in research and biotechnology, though it may be associated with a higher risk of contamination compared to serum from other regions.