bicmay, "Her experience illustrates the layers of anxiety pumping parents endure as they travel, backed up by stories of dumped milk, carry-on pump pushback, alleged “breast milk discrimination” and in-flight crackdowns. Lactating travelers who are not able to pump can face more than embarrassment and discomfort: It could result in infection and reduced milk supply."
https://www.washingtonpost.com/travel/2024/03/21/breast-pump-airlines-carryon-rule-dot/