Melissa Benoist secretly welcomes baby boy

Melissa Benoist has given birth to a baby boy.

The Supergirl star and her husband, Chris Wood, quietly became parents to a son named Huxley Robert Wood over the summer, but only broke the news to fans on Instagram on Friday.

Alongside a snap of the tiny tot's hand, Benoist wrote, "Huxley Robert Wood got here a few weeks ago and this little boy is everything".

Wood, who wed Benoist a year ago, shared the same image on his social media page, gushing about their "amazing" son, and then joking about keeping him off social media for the foreseeable future.

"And no it's probably none of your business... brb (be right back) see you in 18 years," he quipped.

Benoist's new role as a mum comes as she prepares to bid farewell to her role as Kara Zor-El, aka Supergirl, as TV bosses announced the hit show will wrap for good after its upcoming sixth season.

"To say it has been an honour portraying this iconic character would be a massive understatement," the 31-year-old said. "Seeing the incredible impact the show has had on young girls around the world has always left me humbled and speechless.

Benoist added: "(Kara's) had that impact on me, too. She's taught me strength I didn't know I had, to find hope in the darkest of places, and that we are stronger when we're united. What she stands for pushes all of us to be better. She has changed my life for the better and I'm forever grateful."