Kim Kardashian and Kanye West have another bun in the oven via surrogate, and for their fourth time around ... they'll be welcoming another baby boy to the family ... TMZ has confirmed.

Sources tell us Kim and Ye are indeed expecting a fourth child from a leftover embryo they created, which is male. We're told the baby is due in early May.

We broke the story ... Kim and Kanye hired a surrogate in 2017 to carry baby Chicago to term. She was born last January. Remember, Kim has a condition called placenta accreta, which makes another pregnancy for herself life-threatening.

Unclear if KK and KW hired the same surrogate from last time for baby no. 4, but we do know they were close with their previous surrogate and kept tabs on her throughout the pregnancy.

The new baby boy -- first reported by Us Weekly -- will join North, Saint and, of course, Chi ... upgrading their family of 5 to a whopping 6.