This entry discusses lactation and infant feeding for transgender and gender nonbinary (trans) people. The term chest feeding refers to a person’s ability to produce and express milk from mammary and ductal tissue in the chest to feed an infant. This term is preferred when discussing this practice among trans people, because it is gender neutral and more acceptable to people on the transmasculine spectrum who may be reluctant to use gendered language to refer to their body. It also accurately describes the practice in transfeminine people. The following sections address chest feeding for both transmasculine and transfeminine people, including special considerations with hormonal treatment.