Ornithine transcarbamylase deficiency(OTCD) is an X-linked disorder,with an estimated prevalence of 1 per 80000 live births.Female patients with OTCD develop metabolic crises that are easily provoked by non-predictable common disorders,such as genetic(private mutations and lyonization) and external factors;however,the outcomes of these conditions may differ.We resuscitated a female patient with OTCD from hyperammonemic crisis after she gave birth.Hyperammonemia after parturition in a female patient with OTCD can be fatal,and this type of hyperammonemia persists for an extended period of time.Here,we describe the cause and treatment of hyperammonemia in a female patient with OTCD after parturition.Once hyperammonemia crisis occurs after giving birth,it is difficult to improve the metabolic state.Therefore,it is important to perform an early intervention before hyperammonemia occurs in patients with OTCD or in carriers after parturition. Ornithine transcarbamylase deficiency (OTCD) is an X-linked disorder, with an estimated prevalence of 1 per 80000 live births.Female patients with OTCD develop metabolic crises that are easily provoked by non-predictable common disorders, such as genetic (private mutations and lyonization ) and external factors; however, the outcomes of these conditions may differ. We resuscitated a female patient with OTCD from hyperammonemic crisis after she gave birth. Hyperammonemia after parturition in a female patient with OTCD can be fatal, and this type of hyperammonemia persists for an extended period of time. Here, we describe the cause and treatment of hyperammonemia in a female patient with OTCD after parturition. Once hyperammonemia crisis occurs after giving birth, it is difficult to improve the metabolic state. Wherefore, it is important to perform an early intervention before hyperammonemia occurs in patients with OTCD or in carriers after parturition.