Serena Williams' fashion collection is inspired by her daughter.

The 36-year-old tennis champion is branching out into the world of fashion with her eponymous brand Serena and she has revealed that seeing the ''strength'' of her eight-month-old daughter Olympia has encouraged her to spread a message of confidence to other women through her clothing.

Serena - who married internet entrepreneur Alexis Ohanian in 2017 - told Harper's Bazaar: ''My inspiration was strength - bringing femininity and strength to the modern woman.

''My goal is for women to feel confident and sexy when they're wearing it. It's practical and wearable, yet it makes you feel good and walk taller - everyone should have that feeling.

''Ever since [giving birth to] Olympia I was like, 'Okay I have a daughter, I want her to feel good about herself.' She is strong already, so I want her to feel beautiful and I want to spread that message through the collection.''

The 12-piece capsule collection will range in price from $35 to $250 and as well as a range of sports leisure wear, there will be vintage-inspired outfits, structured denim jeans and shirts as well as sexy slip dresses.

Serena is ''proud'' of pursuing her passions, despite people telling her she shouldn't transition into fashion.

Announcing the collection on Instagram, she wrote: ''They say life is about timing. I learned this lesson at age 18, when I chose to play a light tennis schedule because I wanted to go to fashion school. Some criticized my decision, but I knew I had two loves-tennis and fashion--and had to find a way to make them coexist.

''After 15 years of false starts, and people in fashion telling me 'no, it only drove me to work harder. As a result, I discovered what it meant to invest in myself, and I allowed that belief in myself to drive me to reach my dream. Today, I am proud to launch @serena. (sic)''