Already mum to four-year-old daughter, Luna and two-year-old son, Miles, Chrissy took to her Instagram Stories on Sunday evening where she explained she's been bleeding for around a month.
Chrissy, 34, described the constant bleeding as "more than a period" or spotting, but explained a turning point had come over the weekend in which the bleeding became much more severe.
"I was always, always bleeding. I'm about halfway through pregnancy and the blood has been going on for like a month, maybe a little less than a month," she said.
"But we're talking more than your period, girls and definitely not spotting. A lot of people spot and it's usually fine, but mine was a lot.
"But today the difference was it felt as though a faucet had been turned on low and left there. It's so weird because I feel really good, I'm usually at my happiest pregnant mood wise... so that's why it's so hard for me to come to terms with."
Chrissy explained to put it into simple terms, her placenta is "really weak". And despite her baby boy being mega strong and moving around a lot, "his house is falling apart".
"The baby's so healthy," she said.
"Growing so much stronger than Luna or Miles. He moves a lot, so much earlier than they ever did. He's so strong and I'm just so excited for him because he's so wonderful and just the strongest little dude. I can't wait for him.
"He's the strongest little dude in the sh***iest house. His house is falling apart."
Husband John was on hand throughout Chrissy's hospital stay, with the singer rustling up a bedside cheese and ham salad sandwich for Chrissy and sleeping on a chair next to her bed.
Mum Chrissy went on to explain the next few weeks were crucial, and also urged fans and followers not to message her with suggestions as it "isn't helpful".
"What we're doing now is trying to make sure he's got a lot of fluid around him and that I'm resting as much as possible," she said.
Chrissy first revealed she was pregnant last month, announcing the news in John's recent music video and later confirming the happy news on social media.
We're wishing Chrissy and John all the luck for a healthy and happy pregnancy.
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