Chrissy Teigen has been hospitalised due to heavy bleeding.
The 34-year-old model is pregnant with her third child and has spent the last few weeks on bed rest but was admitted to a medical facility over the weekend after she began bleeding more heavily than she'd previously experienced, but she insisted she is feeling "really good" in herself.
She told fans: "We all know I've been on bed rest for a few weeks.
"And that's super serious bed rest, like get up to quickly pee and that's it. I take baths twice a week, no showering... I was always, always bleeding.
"I'm about halfway through pregnancy and blood has been going for a month. So like, maybe a little less than a month. We're talking more than your period, girls, but definitely not spotting. A lot of people spot and it's usually fine.
"Every time I'd go to the bathroom it would be blood, but honestly, just laying there would be blood.
"But today, the big difference was that it kind of was like you were to turn a faucet on to low and leave it there. It's so weird because I feel really good. I'm usually at my happiest pregnant, mood-wise.
"I feel happier than I do not pregnant. That's why it's so hard for me to come to terms with [the situation]... It was at the point today where it was never stopping bleeding."
The 'Lip Sync Battle' star - who also has Luna, four, and Miles, two, with husband John Legend - reassured her fans that while her placenta is "really weak", the baby is healthy.
She added on her Instagram Story: "In the simplest of terms, we can say my placenta is really, really weak.
"I feel really good. The baby is so healthy, growing stronger than Luna or Miles. He moves a lot. He moves so much earlier than they ever did... he's so different than they were. He's strong...
"But basically, he's the strongest coolest dude in the s******** house. His house is just falling apart. It didn't have a good foundation to begin with."
Chrissy and her baby need to get through the next few weeks to make it out of the "danger zone", which she admitted is scary but in a way "where there's nothing to do".
And the 34-year-old star appealed to her fans who are also doctors to stop sending unsolicited medical advice.
She said: "If you are a doctor, I cannot express enough how badly I'd like you to stop your guessing games.
"You have to trust me that I have very good doctors, who know what they're doing. There's so much more than you can ever imagine. I share a lot, but not absolutely everything.
"So trust me when I say they know and I just want to keep things so simple for you guys."
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