《资治通鉴·汉纪·汉纪二十二》
然而，听说到现在张美人也未曾怀孕。而且，即使是羌人、胡人，还要杀死头胎婴儿，以洗女人的肠肚，使未来所生之子血统纯正。何况是天子，怎能亲近已嫁过人的女子！
且羌、胡尚杀首子以荡肠正世，况于天子，而近已出之女也！
However, it is said that even now Zhang Meiren is not pregnant. Furthermore, even the Qiang and Hu people would kill their first-born baby so as to cleanse the woman's bowels and make the future child's bloodline pure. How much more so the emperor, how can he be intimate with a woman who has already been married!