Pippa Middleton has welcomed her first child into the world.

Pippa Middleton and her husband James Matthews have welcomed their first child into the world.

A spokeswoman for the couple said their baby boy was born on Monday at 1.58pm local time (11.58pm AEST). Both he and their mother are reportedly healthy.

The boy’s name or photo has not yet been shared.

A spokesman for the Duke and Duchess of Cambridge said they were “thrilled” for Pippa and her husband.

We learned in June that Princess Charlotte, Prince George and Prince Louis were expecting a cousin this year, with Pippa confirming the news she was pregnant in a UK magazine.

In her regular column for Waitrose Kitchen, the 35-year-old spoke about her pregnancy – which had been reported since April – for the first time.

The events planner and columnist said that unlike her sister, she did not suffer hyperemesis gravidarum – a severe type of morning sickness.

“I was lucky to pass the 12-week (mark) without suffering from morning sickness,” Pippa, who has taken her husband’s last name, wrote.

“That meant I was able to carry on as normal and continue most of my sports with better knowledge and, more importantly, professionals to learn from.

“I’ve noticed my body change, but through exercise I feel it’s being strengthened.”

Pippa and James, a former racing driver and hedge fund manager, married on May 20 last year in a ceremony that got almost as much attention as a royal wedding.

Rumours of Pippa’s pregnancy first arose in April, shortly before the Duchess of Cambridge gave birth to her third child, Prince Louis.

Pippa and James surprised some commentators by their appearance last Friday at Princess Eugenie and Jack Brooksbank’s Windsor Castle wedding.

But despite her large baby bump she looked at ease when she joined the other guests who included Robbie Williams and Hollywood star Demi Moore.

The news follows the Duke and Duchess of Sussex’s announcement they are expecting their first child.