welcomed her third child, a son named Journey, only nine months ago.

And the Transformers star lost the weight very quickly, wowing her fans within weeks of leaving the maternity ward.

On Friday the 31-year-old wife of Brian Austin Green gave a hint at how she was able to shed the weight when she was spotted leaving a yoga session in .

Post workout: Megan Fox was seen leaving her yoga session in LA on Friday

Rock on: Fox looked headbanger chic a white KISS rocker T-shirt with pink accents

Fox looked headbanger chic a white KISS rocker T-shirt with pink accents.

A pair of black and pink capri leggings from Champion were fun.

But they paled when compared with her fuzzy slides that had pink, grey, black and blue in them.

She needs a large handbag: The star was weighed down by a pink yoga mat, a bag from BURRO and a purple bag as well as a bottle of water and her cell phone

Tight: A pair of black and pink capri leggings from Champion were fun

Cute look: But they paled when compared with her fuzzy slides that had pink, grey, black and blue in them

With baby number three: Fox with her son in her tummy in May 2016

The star was weighed down by a pink yoga mat, a bag from BURRO - an artsy store offering a selection of women's apparel, handbags, art books, stationery in Venice Beach, California - and a purple bag as well as a bottle of water and her cell phone.

Fox met Beverly Hills, 90210 alum Green in 2004 and they wed in 2010. They are already parents of sons Noah, aged four, and Bodhi, aged three.

Green shares son Kassius, 14, with ex Vanessa Marcil.  

Happy together: Fox met Beverly Hills, 90210 alum Green in 2004 and they wed in 2010; here they are seen in 2014

Megan and Brian's son Journey River Green arrived in August.

'I knew I was always going to be a mother; I felt like that was always a big part of my path,' she said in June on Chelsea Handler's Netflix series, Chelsea.

'But I never knew I was going to have three in such rapid succession.' 

The Teenage Mutant Ninja Turtles actress filed for divorce in August 2015 after five years of marriage but then got pregnant with Brian again, making her want to reconcile.  

Her tots: They are already parents of sons Noah, aged four, and Bodhi, aged three; here she is seen with two of her kids in April