Now, the star, 35, has revealed that that her body has struggled to adapt ever since, describing it as being "stuck" and "paused in time."
In a post on Instagram, the mother of two wrote: "It’s really weird when you lose a baby and your body gets paused in time.
"Usually you’d gain your 'yumyums I’m praaaagnant!' weight, then put on the weight of your little bebe.
"Then, ideally, you’d have your baby. And you would feed it from your boobs and your body would know to charge through and do what it does to get you back into fighting shape."
Teigen added: "But man. When you lose a baby halfway through, your body just pauses. It has nothing to do. No one to feed.
"And you’re just… stuck. Stuck with saggy boobs that were prepping to be milk bags, a belly that was ready to bake."
She said: "I would be lying if I said this did not majorly suck. Not only are you ummmm extremely, diabolically sad at what could have been, but you have this daily reminder every time you look in the goddamn mirror."
Teigen's searingly honest post has received more than 405,000 likes, as well as over 8,000 comments — including many messages of praise and support.
Paris Hilton wrote: "You are beautiful inside and out."
Selling Sunset star Christine Quinn shared: "Stay strong angel."
A fan told her: "I don’t ever comment but wanted to thank you for sharing and showing us that celebrities are normal. Young people don’t get this view often enough. Sharing your ups and downs is priceless and lifting you up with all I have."
Teigen – who shares a young son and daughter with her husband, singer John Legend – was 20 weeks pregnant when she was told her baby wouldn't make it.
In a post on Instagram last October, the model and author revealed her "deep pain" as her little boy wasn't able to survive, despite "bags and bags" of blood transfusions.
Accompanying a raw black and white image of her crying while sat on a hospital bed, she added: "We are so grateful for the life we have, for our wonderful babies Luna and Miles, for all the amazing things we’ve been able to experience.
"But every day can’t be full of sunshine. On this darkest of days, we will grieve, we will cry our eyes out."
Want lifestyle and wellness news delivered to your inbox? Sign up here for Yahoo Life’s newsletter.