Queen Bey, 35, announced in February that she and the rapper, 47, were expanding their family.
"We would like to share our love and happiness," Beyoncé captioned an Instagram photo of her bare bump at the time. "We have been blessed two times over. We are incredibly grateful that our family will be growing by two, and we thank you for your well wishes."
The "Hold Up" singer documented her pregnancy on social media and made several red carpet appearances while expecting. Although she had to pull out of her headlining Coachella appearance, she attended the Grammys, the Beauty and the Beast premiere and the inaugural Wearable Art Gala at the California African American Museum.
The couple's new twins join their daughter Blue Ivy, 5. "They have been trying for a long time and now to be blessed with twins they are so over the moon. It's even better than they wished for," a source exclusively told Us earlier this year. "Blue is so excited to be a big sister!"
Beyoncé and Jay Z tied the knot in 2008 and recently celebrated their ninth wedding anniversary.
Showbiz 411 was the first to report the twins' birth.
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