A baby shower was a Human celebration often held for expectant parents, during which the guests brought gifts, such as toys, for the infant, or things the parents could use to care for the baby.
In 2371, Julian Bashir and Miles O'Brien were planning on throwing a baby shower for Ensign Vilix'pran. They planned on bringing gifts: a hatchling pond (O'Brien) and baby clothes made by Garak (Bashir). Sisko planned to attend, but didn't say what gift he would bring. (DS9: "Heart of Stone")
In 2378, Seven of Nine created a holoprogram to interact with holographic versions of the USS Voyager crew that included a baby shower for Tom Paris and B'Elanna Torres, who were expecting a child at the time. (VOY: "Human Error")