The Nashville star welcomed her daughter along with fiancé Wladimir Klitschko on Tuesday, her rep has confirmed.
The new parents named their newborn daughter Kaya Klitschko.
The 24-year-old’s rep told a US magazine a message from the couple, reading: “We are over the moon and madly in love."
The star revealed her pregnancy earlier this year, and has been showing off her pregnancy bump, set off by her famous petite frame.
Hayden had previously revealed that she was ‘born to be a mother’.
She previously said to Glamour magazine: "I've lived a very big life, and I don't feel my age, and I feel like I was born to be a mother.
"Sometimes people speak about [having kids] like, 'Your life ends - you're never going to be able to do anything again!' And I'm like, 'What are you talking about?'"
She added: "Motherhood is the most beautiful, exciting thing, and there's nothing that I feel like I can't accomplish while having children in my life."
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