Tokyo Olympic gold medallist Emma Twigg and her wife Charlotte have welcomed their first child into the world.

Posting on social media on Friday, Emma announced the birth of a son, named Tommy, on April 26 at Waikato Hospital with Charlotte saying the experience was already a life highlight.

"Chuffed, exhausted, totally besotted," Charlotte wrote on Instagram accompanying a series of photos of the new mothers and baby.

"Of all the things I've held in my arms, this is the best by far."

"I always believed when my Grandpa Bruce left this world, he gave me Emma. Born just days before Gramps' birthday, Tom Bruce Twigg, you have every inch of my heart and more."

The birth of a son caps an event-filled period of life for Emma, who first met Charlotte in 2018 and married in January 2020.

A year and a half later, Emma would go on to win her first gold medal at the 2021 Tokyo Oympics in rowing's single sculls.

Twigg had retired after the 2016 Rio Olympics after her second consecutive fourth placing in the womens single scull final, but decided to start rowing again in 2018.

She told the Herald in December last year that a campaign towards defending her gold medal at the Paris Olympics in 2023 was "definitely on the cards". She'll now face that task with the extra motivation of impressing her growing whanau.