Sharing a picture of their new baby on social media, the couple included the caption "Psalm West"
She also included the message: "Beautiful Mother's Day. With the arrival of our fourth child. We are blessed beyond measure. We have everything we need."
The Keeping Up With The Kardashians star has three children with husband West - North, Saint and Chicago.
Psalm West pic.twitter.com/F0elQd1cJq— Kim Kardashian West (@KimKardashian) May 17, 2019
Despite often criticised over lifestyle choices, the couple have both been open about their Christian faith.
Kanye West has recently shared videos from a church gathering he has been hosting which includes much gospel music.
The word Psalm means song or hymn with the book of Psalms one of the most commonly read in the Bible.
The child was born using a surrogate.
Kardashian and West were pictured (see above) at the Met Gala earlier last week.
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