It wasn't long before fans weighed in with their parenting advice.
"You not suppose to drink alcohol if you breastfeeding your baby," one follower commented.
Snooki shares her newborn baby Angelo with husband Jionni LaValle. The couple are also parents to Lorenzo, 6, and Giovanna, 4.
While it's not clear when Snooki pumped the milk for her little boy, she wasn't necessarily putting him at risk.
According to Australian Breastfeeding Association, planning ahead can allow you to express some milk for your baby ahead of time. Your baby can have this milk if you miss a feed while drinking, or while you are waiting for the amount of alcohol in your milk to drop.