ABC News' Diane Macedo Expecting Second Baby After 'Unexplained' Fertility Issues: 'So Thrilled'

ABC/DANNY WEISS

This just in: ABC News anchor Diane Macedo is pregnant!

The 39-year-old is expecting her second child, a daughter, with husband Thomas Morgan, PEOPLE can exclusively confirm.

Macedo, who already shares a 2-year-old son with Morgan, is due this fall.

The news personality tells PEOPLE that her current pregnancy comes after she and her husband "struggled with unexplained fertility issues for a long time."

"My husband and I are so thrilled to announce that we're expecting our second baby this fall," she says. "To not only have our two-year-old son but now to be able to say we're expecting a daughter, we feel especially grateful."

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ABC/DANNY WEISS

ABC/DANNY WEISS

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Macedo shares that her pregnancy "feels less real" than when she was pregnant with her first baby.

"It hasn't quite sunk in yet," she says. "Part of that just might be the bizarre nature of what this year has been like. It could also be the fact that I was working full time, writing a book, and raising a toddler at the same time. This was a year of multitasking unlike any other!"

The anchor explains that her experience getting pregnant with her baby-on-the-way wasn't easy.

"There was a moment last year when I thought I was pregnant only to find out our IVF transfer didn't take. It was disappointing and heartbreaking," she says. "I think that made this pregnancy feel more fragile to me, I was afraid to celebrate it — afraid I'd jinx it somehow."

"So it feels really nice to finally be able to share it. In the back of my head I still have those worries that something could go wrong but I'm also realizing this is a special and fleeting time, and I'm ready to cherish and celebrate it while I still can," adds Macedo.

ABC/DANNY WEISS

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Along with her exciting baby news, Macedo is also celebrating the release of her first book later this year.

Her upcoming book The Sleep Fix: Practical, Proven, and Surprising Solutions for Insomnia, Snoring, Shift Work and More, out Dec. 14, is a user-friendly guide to getting better sleep — something Macedo has struggled with for years.

"The irony of writing a book like this while pregnant is that pregnancy inherently creates its own sleep obstacles, so in a way I've been testing these sleep solutions on myself all over again," she tells PEOPLE, teasing, "Thank God they've worked or that would have been doubly disappointing!"

"So I decided to write the book so others don't have to suffer the way I did. I made all the mistakes so you don't have to!" she continues.

"I also want all the 'bad sleepers' out there or the people who think they sleep fine but regularly doze off in waiting rooms, to know that it is not normal and it's not inevitable, you have a sleep problem — and more importantly you can fix it," Macedo says.