Hilton posted a photo on Instagram of what appeared to be her newborn baby grasping her thumb.
“You are already loved beyond words,” Hilton wrote with a blue heart emoji.
US entertainment media reported that the baby boy had been born via surrogate.
The former reality TV star, 41, had opened up in an interview last month about beginning an IVF process during the pandemic with her husband, an investor whom she married in 2021.
She told People Magazine that “because the world was shut down” early in the Covid-19 pandemic, it was the “perfect timing” to “get all of the eggs stocked and ready.”
In a statement published Tuesday by People, Hilton said that her family’s “hearts are exploding with love for our baby boy.”