Family background and marriage to then-Crown Prince Ao
Empress Xu was the daughter of Xu Jia (許嘉), the Marquess of Ping'en and the brother of Emperor Xuan's first wife Empress Xu Pingjun, who was the mother of Emperor Yuan. Emperor Yuan frequently grieved for his mother because she was murdered while still young by Huo Guang's wife Xian (顯), so he resolved to marry a daughter of the Xu clan to his son, Crown Prince Ao (劉驁), and he eventually decided on his cousin. When the young couple got married, then-Crown Prince Ao loved his wife dearly. However, they had no children; then-Consort Xu miscarried a male child while her husband was crown prince, and would miscarry a female child when she later became empress, but she would have no births. She was described to have been, unlike even most noble women of the time, well-learned in literature and formal writing.