Reforms to the US welfare system that made cash transfers conditional upon work were associated with an increase in infant mortality of 3.1 deaths per live birth for foreign-born Mexican women.

"Reforms to the US welfare system were associated with an increase in infant mortality rate for children of foreign-born Mexican women of 3.1 deaths per 1000 live births (SE: 0.001), from a baseline rate of 4.23–6.22 deaths per 1000 live births depending on the state."