Diaphragmatic hernia (DH) during pregnancy is rare with only 30 cases reported worldwide in the last 50 years. The mortality rate is as high as 50%. Low level of suspicion is required to make the diagnosis. This is the first documented case report of a third trimester maternal DH in Queensland, Australia. DH diagnosis and decision of treatment in the obstetric population can be difficult and challenging. A multidisciplinary team is required to optimise maternal and fetal outcome.