Model and cookbook author Chrissy Teigan shared a heartbreaking social media post on Wednesday, saying she and her husband John Legend had lost their child, days after she posted about her pregnancy complications online.

"We are shocked and in the kind of deep pain you only hear about, the kind of pain we’ve never felt before. We were never able to stop the bleeding and give our baby the fluids he needed, despite bags and bags of blood transfusions," she wrote in a Twitter post late Wednesday.

"It just wasn’t enough," she added.

34-year-old Teigan, who was expecting a son, had spent days in hospital in Los Angeles after being admitted at the weekend.

In the long social media post, accompanied by a black-and-white picture of her, Teigan also revealed that the couple had named their lost child Jack. "We never decide on our babies' names until the last possible moment after they’re born, just before we leave the hospital," she said.

"But we, for some reason, had started to call this little guy in my belly Jack," Teigan wrote further adding "He will always be Jack to us."

In a separate Twitter post later, Teigan described her feelings about the miscarriage. "Driving home from the hospital with no baby. How can this be real," she wrote.

Meanwhile, her husband and musician Legend tweeted, "We love you, Jack."

The couple announced their pregnancy in August online. They tied the knot in September 2013 after being together for six years. 

Teigan and Legend have two other children together - a four-year-old daughter named Luna and a two-year-old son named Miles.