Glamour Magazine profiled both women in an effort to spread awareness of their new venture, which promises to make no topic off limits.
"I was in a school play, wearing a gray beard and this pad the size of a skateboard and thinking, What is happening to me?" she explains in relation to getting her first period in fifth grade. "We want girls to know what their [body is going through] so they don't feel scared or ashamed or gross."
And the whole idea was born more than two years ago when Biel and her husband Justin Timberlake decided they were ready to have a baby.
“Now what happens?” she wondered after going off birth control. “I’ve been on the Pill for so long; how hard will it be to get pregnant?”
Curious about those and other basic facts, Biel realized how little she knew about sex. “Suddenly I realized I really didn’t know what’s going on inside my own body,” says the 33-year-old actress. “It was shocking.”