She shared a photo of herself cradling her stomach as she posed with her two sons.
The Countryfile presenter and her husband, rugby league ace Richie Myler, are already parents to boys – Ernie, six, and Louis, four.
The happy news had already been left out after videos posted on social media of his participation in the BMW PGA Championship Celebrity Pro-Am on Wednesday.
Another competitor, Inci Mehmet, said Helen expected this when she uploaded a video of the sports star swinging a golf club.
The professional sportswoman wrote: “An absolute god of a woman! @helenskelton learned the game 6 months ago and now enlightens it at @bmwpga Pro-Am while pregnant !!! “
In photos taken at the event, the former Blue Peter presenter was seen in a navy blue dress.
The form-fitting style hugged her growing belly and she continued her golf course look with white sneakers.
The Holiday Hit Squad host protected herself from the bright sun by sporting a visor and appeared determined to show off her skills on the green.
Daredevil Helen loves athletic challenges. She was the first woman to kayak the Amazon River solo and she walked a tightrope through the Battersea Power Plant and completed a 78-mile ultra-marathon.
She was recently seen in Celebrity SAS: Who Dares Wins by C4. She managed to smash competitor Nikki Sanderson’s nose in a boxing match and endured physical and emotional chores to reach the final.
The mom-to-be said her appearance on the show made her little boys be braver, revealing, “I showed [my kids] little bits of the show and they love it. My little boy a long time ago saw a girl on a roller coaster and he said, “She’s brave like you, Mom”.
Hollyoaks star Nikki showed there were no hard feelings as she was one of the first celebrities to congratulate Helen on her good news, writing on Instagram: ‘Love’ and added five emojis loveheart.
While former Corrie actress Catherine Tyldesley wrote: “Oh honey, huge congratulations”
Helen has yet to reveal her due date and whether she has found out the gender of her baby. Let’s just hope that this time around the delivery of her third child is more peaceful and stress-free than when she had her second. Helen revealed the circumstances of the childbirth alone in 2019, when she said: “I was in France and my husband was in England, and no one caught up with me in time.
So I gave birth with just my three year old next to me, repeatedly hitting me on the head with a plastic sword, because he thought we were playing dinosaurs. “
She described the experience as’ terrifying ‘and added,’ But I had no choice, I just had to keep going. “