Reese Witherspoon's eldest child, Ava Elizabeth Phillippe, recently turned 21. A week after celebrating her daughter's birthday, the actress recalled how she dealt with motherhood at a young age and revealed she was "terrified."

Reese Witherspoon got pregnant with Ava Phillippe when she was just 22, and welcomed her into the world after turning 23. Opening up about her first pregnancy journey on "The Drew Barrymore Show" on Tuesday, the actress said: "I was terrified. I got pregnant when I was 22 years old, and I didn't know how to balance work and motherhood."

"You just do it. ... I was just like every other mom and dad trying to figure it out. There's a lot of compromise. Every bit of that sacrifice is truly worth it," the 44-year-old added.

Witherspoon is today a mother to three children. She shares Ava and 16-year-old son Deacon with ex-husband Ryan Phillippe, and seven-year-old son Tennessee James with husband Jim Toth.

When Witherspoon welcomed her first daughter in 1999, she didn't even have "steady work." However, the "Big Little Lies" alum now says that she now wakes up every day for her family, "not movies or (her) job."

"I made movies but I hadn't established myself as someone who could demand that it shoot close to my kids' school. (I) didn't have any real power or leverage within my industry," she said about the struggles she faced while working when she was a new mother.

"The Morning Show" star had earlier also admitted she was "scared" about becoming a mother during her pregnancy. In a YouTube video for her production company 'Hello Sunshine' in September last year, Witherspoon said: "I didn't know what it was going to do to my job or my career. Your entire life will change, everything you believe, every piece of food you eat, every piece of independence you have. You can't go out without thinking of another person."

ava phillippe
Ava Phillippe and Reese Witherspoon attend the WSJ. Magazine 2017 Innovator Awards at MOMA on November 1, 2017 in New York City Getty

However, the Oscar-winner is "glad" she started her family at a young age, as she said: "I find that having little kids is more physical and it's just really hard on your body. ... I had one at 23, one at 27 and then again at 37. And oh, my God, having a baby at 37 was so much harder. This is just me being real."