Jaycee Dugard talks to Diane Sawyer about giving birth in Phillip Garrido’s backyard

Kidnap victim Jaycee Dugard says she didn’t know she was pregnant when she gave birth to her first child.

Dugard had been abducted by Phillip and Nancy Garrido when she was 11 years old, handcuffed, raped and imprisoned for 18 years. Now 31, she is telling her story in the memoir “A Stolen Life” and in an exclusive interview with ABC News’ Diane Sawyer. Watch a clip below.

“Now I can walk in the next room and see my mom,” Dugard said in her first interview. “Wow. I can decide to jump in the car and go to the beach with the girls. Wow, it’s unbelievable, truly.”

Dugard told Sawyer how she gave birth to her first child, Angel, at age 14 in the Garridos’ deranged backyard. Angel was the first of two children she had with Garrido.

“I didn’t know I was in labor,” she said. “I was still ... locked at that time. Just scared.”

She writes that the Garridos told her she was pregnant when she was 13 after she began gaining weight but not knowing why. She said she knew nothing about sex when she was kidnapped and watched birthing videos to prepare for labor because there wouldn’t be a doctor to assist her with the delivery.

“[It was] very painful, then I saw her -- she was beautiful,” Dugard said, teary-eyed. “I felt like I wasn’t alone anymore. I had somebody that was mine. I wasn’t alone and I knew I could never let anything happen to her. I didn’t know how I was going to do that but I did.... You just do what you have to do to survive.”

The full interview will air on “Primetime” Sunday night.