Mark Zuckerberg used a happy announcement to share some thoughts on a topic most people don't like to talk about.

It sometimes feels like your newsfeed is an endless onslaught of people's happy family news: Engagements, weddings, and Pinterest-style pregnancy announcements. On Friday, the Facebook founder and his wife Priscilla Chan joined the fray, announcing they were expecting a baby girl.

"This will be a new chapter in our lives. We've already been so fortunate for the opportunity to touch people's lives around the world," he wrote in his announcement. Then he shared some sadder new: "We've been trying to have a child for a couple of years and have had three miscarriages along the way."

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According to the UK's National Health Services website, around one in six pregnancies end in a miscarriage. In most cases, they can't be prevented: They're usually a result of abnormal chromosomes in the fetus. But the subject comes with a lot of stigma and silence, which Zuckerberg wanted to address.

"You feel so hopeful when you learn you're going to have a child. You start imagining who they'll become and dreaming of hopes for their future. You start making plans, and then they're gone. It's a lonely experience," he explained. "Most people don't discuss miscarriages because you worry your problems will distance you or reflect upon you — as if you're defective or did something to cause this. So you struggle on your own."

He continued: "We hope that sharing our experience will give more people the same hope we felt and will help more people feel comfortable sharing their stories as well."

Fortunately, he said, at this point in Priscilla's pregnancy, the chance of miscarriage is very low, and mom and baby are doing well. In fact, in the most recent ultrasound, "she even gave me a thumbs up 'like' with her hand, so I'm already convinced she takes after me," Zuckerberg said.

Read the touching post:

Priscilla and I have some exciting news: we're expecting a baby girl!This will be a new chapter in our lives. We've...

Posted by Mark Zuckerberg on Friday, July 31, 2015

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