Abstract
Ornithine transcarbamylase deficiency is the most common urea cycle disorder. If left untreated, pathogenic variants in the OTC gene can cause hyperammonemia leading to neurotoxicity, coma, and death. A comprehensive overview of ornithine transcarbamylase deficiency is presented including the genetic cause; varied age of onset, clinical presentation, and severity; diagnostic testing; and lifelong and anticipated future treatments. More specifically, there is a focus on the prenatal, natal, and postpartum course and treatment recommendations for genetic heterozygous (carrier) females and hemizygous male newborns with ornithine transcarbamylase deficiency.