It's tough to keep a pregnancy a secret when you're in the public eye, and for a while, Beyonce thought the jig was up.
The singer said at one point, she was thinking, "everyone knows".
Beyonce said it became particularly difficult to hide her baby bump when the she performed for sold-out crowds at New York's Roseland Theatre in August.
The singer spoke at a screening of her new concert DVD in New York.
Fans can get a behind-the-scenes look at the Intimate Nights concerts on her new Live at Roseland DVD, out in New Zealand on December 5.