Alex, 39, took to Instagram to announce her baby news, writing: "Charlie and I are very happy to confirm that we're expecting a little baby in the new year. Absolutely delighted and feel very lucky that we're about to become parents. #andbreatheout #newbabyalert."
The pretty co-host of The One Show married insurance broker Charlie on New Year's Eve last year, in a wedding exclusively covered by HELLO! magazine.
Alex and Charlie are expecting their first baby
Shortly after her wedding, Alex completed a documentary about fertility, which prompted her to reveal her worries that she had left it too late to have children.
"Safer sex is important but so is learning about fertility otherwise you end up where I am now saying: 'Oh egg freezing, I don't know about that,'" said Alex.
"As most girls I spent all of my teenage years, twenties, thirties, doing everything I could to avoid getting pregnant and then… a day arrives and then you go 'gosh, maybe we should have a baby'."
The couple married on New Year's Eve last year
The presenter also spoke about her relationship with her New Zealander beau Charlie.
"We met when I was 34, I had just moved to London to do the job of my dreams. We dated and messed about a bit," she said.
The parents-to-be have just been on holiday to Sri Lanka
"The penny hadn't dropped for me, I had just met this boy, I had a lovely job although it's not more important than a family. I want to make that clear. People say 'oh, you're one of those career girls'. No, I just happen to have a career… We got married and less than two days later the first person said 'So, when are you going to have a baby?' It's a very personal question."
She added that her own mother went through menopause at the early age of 43, and so she has "a five-year window potentially to get this done." However, Alex also revealed at the time that she and her husband "haven't started trying in earnest."