Actress Jessica Biel is now a parent to five-month-old son Silas Randall along with her husband Justin Timberlake.

Yet Biel says it wasn’t until she began trying to conceive almost two years ago, that she realised she knew nothing about her body and how contraception works.

The 33-year-old said, “[I thought] Now what happens? I’ve been on the pill for so long; how hard will it be to get pregnant?”

Jessica Biel with son Silas Randall Timberlake. Image via Instagram.

Biel explained that she was also misinformed about so much basic information surrounding conception.

"Suddenly I realised I really didn't know what's going on inside my own body," she says. "It was shocking."

It wasn't until Biel met activist Saundra Pelletier, who is the founder of not-for-profit health care organisation WomanCare Global, that she realised just how ignorant she was. They began talking and now the pair are launching a series of online videos that will cover everything from puberty to contraception.

Saundra Pelletier (L) is working with Jessica Biel to educate young women on how their body's work. Image via Twitter.

Although talking about periods and birth control isn't an overly glamorous topic for the Seventh Heaven star to be discussing, Biel who gave birth to her first child in April, says she remembers how embarrassed she was when she got her first period in year five.

"I was in a school play, wearing a grey beard and this pad the size of a skateboard and thinking, 'What is happening to me?'" she said. "We want girls to know what their [body is going through] so they don't feel scared or ashamed or gross. The tone is informative but also goofy, smart, witty."

Biel and Pelletier plan on spreading the message through open discussions on their video web series. "We share girl stories, fears, and insecurities. The tone is informative but also goofy, smart, witty," Biel explained.

Video series co-host Pelletier, whose organisation WomanCare Global delivers contraceptives and other feminine-care products to women in the developing world, added that, "Jessica and I realised we can help change this."

"You have to have the courage to stand up for what you believe in," Biel recently told Glamour Magazine.

What did you discover about your body after pregnancy?

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