Why Blake Lively felt she wasn't "equipped" to deal with motherhood.

It’s been over a decade since Blake Lively first came into our lives as a mid-noughties IT girl.

Since her Gossip Girl days, Lively has gone on to star in a bunch of movies and to build a family with her husband Ryan Reynolds.

Now Lively, 30, has spoken candidly to Cosmopolitan Australia (issue on sale Monday, 9 April) about what it’s really like balancing her career with her young family.

When Cosmo asked Lively what surprised her about being a mother, the mum-of-two told the publication at first she didn’t feel “equipped” to be a mother.

“Before, I remember thinking: ‘I have no idea what I’m doing! I have a life in my hands and I’m not equipped to do this, because I don’t have the knowledge I need to take care of the most precious, fragile thing in the world – my baby’,” she explained.

“It felt like being a passenger on board a plane and being told: ‘By the way, you are now going to be piloting the plane’.”

The Shallows star reassured fans that you do eventually figure it out, she also reiterated that her family is her number one priority.

"Family is the most important thing in the world to me, and everything else I do supports that. My personal life has always been a priority."

Lively is hoping to pass this love of family down to her daughters James, three, and Ines, one.

The actor and activist also admitted she has help, which means she's still able to keep working while her daughters are young.

"My parents [Ernie and Elaine] are pretty much the nannies!" she told Cosmo.

"They are the best baby nurses. They raised five kids so they know what they're doing," she explained. "They visit for long periods of time and then they'll go away and make us beg them to come back."

In February this year, Lively got refreshingly honest on Instagram about how long it took her to lose her baby weight after Ines was born.

The second-time mum said she enlisted the help of a personal trainer to get down to her goal weight, over more than a year of putting in long hours at the gym.

“Turns out you can’t lose the 61 lbs you gained during pregnancy by just scrolling through instragram [sic] and wondering why you don’t look like all the bikini models,” she wrote.

“Thanks @donsaladino for kickin my A double S into shape. 10 months to gain, 14 months to lose. Feeling very proud.”

You read Blake Lively's full interview in the May issue of Cosmopolitan, which is on sale Monday, 9 April.