The 31-year-old actress gave birth to their daughter at Cedars-Sinai Medical Center in Los Angeles on Tuesday, according to TMZ.
The couple – who got engaged in February – went to the hospital by themselves, unaccompanied by family members or bodyguards.
Earlier this year, the actress told Marie Claire magazine of her birth plans and Ashton's involvement: "He'll be head to head, not head to vag."
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