Jessica Biel Was 'Shocked How Little' She Knew About Her Own Body Until She Struggled to Get Pregnant in Her 30s (Exclusive)

Through her debut children's book, Biel hopes to de-stigmatize conversations surrounding menstruation

Before Jessica Biel was in her 30s, the actress and producer never felt comfortable talking about menstruation — and it blew her mind when she realized how little she knew about her own body.

In light of the release of her debut children's book, A Kids Book About Periods, in which Biel aims to de-stigmatize the topic of menstruation for young readers, the Candy actress opened up about her own experience getting to know her body.

"I was probably in my 30s when I was married and we were thinking about trying to start a family, and that's when all these questions came up. It wasn't as easy as I thought it was going to be," Biel, 42, says.

"When I was in that phase of my life where I was really trying to build my family, I was shocked at how little I knew," she continues. "I mean, I knew the basics. I'd been dealing with the basics forever. But as I got older, things were changing and my cycle was different and I wasn't getting pregnant. What was going on? And I had a lot of trouble the second time getting pregnant as well."

Related: Jessica Biel Reveals 9-Year-Old Son’s Reaction After Reading Her Book About Periods: ‘He Was So Cool About It’ (Exclusive)

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That struck a chord with Biel, who simply wanted more "answers," "tools" and "resources."

"I didn't know where to turn. And I kept coming up on people who I knew, loved and admired and respected, who also had questions. It just kept in my mind going, 'How is it possible that all of us have all these questions?' I thought it was just me, I thought I was this idiot," she explains. "And then it just kind of became clear that a lot of us don't know enough about our bodies."

She continues, "I mean, even now I'm still working on feeling confident saying to, I don't know, a colleague or someone like, 'Excuse me, I really need to use the restroom. I need to change my tampon. I really need to go right now.' I still have trouble just outwardly saying that, and that's really not okay with me."

It was for these reasons that Biel — who shares sons Silas, 9, and Phineas, 3, with Justin Timberlake — created the children's book in partnership with PERIOD.

Writing the book was a "wonderful, natural accident" and she decided that this would be the most efficient way to start the conversation about female reproductive health.

Related: Jessica Biel Was Planning on 'Quitting' Hollywood Before Success of The Sinner

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"I wanted to cover all the really technical things that happen because I really believe that our kids are capable and we don't give them enough credit about what they can understand," she says.

She adds of what her priorities were when writing it, "Telling the truth about my own experience, hoping to inspire other people to feel confident telling their truthful stories, and then telling the facts of, 'This is what it is.' Can we change our mind around it? Can we realize that the process of having a menstrual cycle is powerful and absolutely incredible?"

A Kids Book About Periods is now available.

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