Aid sanctions are a type of financial punishment imposed on a country by other countries or international organisations in response to a political coup, armed conflict, or human rights abuses. Humanitarian catastrophes in Burkina Faso, Sudan, and Myanmar have brought aid sanctions to the centre of the foreign affairs strategy debate because of their inadvertent negative effects on human health. Our analysis investigates the effects of aid sanctions from 1990 to 2019 on maternal and child mortality. These questions are particularly relevant in the context of the abrupt shift in US foreign aid policy in 2025, leading to aid prohibitions that might resemble aid sanctions in their effects.