Chrissy Teigen Reveals She Was Pregnant During Breast Implant Removal Surgery but Didn't Know It

Chrissy Teigen is opening up about her pregnancy story.

One day after it was revealed that Teigen and husband John Legend are expecting their third child, the always candid cookbook author, 34, set the record straight on the timing of their happy news — as many fans had noted that Teigen recently underwent breast implant removal surgery.

“Oh, it's quite a story. Lol,” Teigen wrote on Twitter in response to a fan who said they were “confused” about the timeline.

“I did the routine pregnancy test you do before surgery. It said negative. It was not negative,” the soon-to-be mother of three explained. “A few weeks after surgery, I took a test. And for many years now, I've taken pregnancy tests almost every month, praying to see a positive one day. Just wishful thinking. I never had a positive before.”

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On June 19, the day her husband released his latest album, Bigger Love, Teigen took a pregnancy test — which turned out to be positive.

“I was scared,” she wrote. “Was pretty positive you shouldn't get your boobs out while pregnant? Pretty sure.”

“So we prayed to the boob surgery gods that everything would be okay. Went to every appointment terrified. Even without the surgery, I didn't think I could get pregnant naturally anyway. So the odds just felt...bad,” added Teigen, who conceived their eldest children, daughter Luna, 4, and son Miles, 2, through in vitro fertilization.

Continuing, she wrote, “But what they say so often can be true. When you give up on trying, life has a way of surprising you. In summary, my boobs hurt.”

Teigen went on to share that despite the good news she’s still “very worried.”

“Part of me misses the safety of my perfect embryos, created in their little dish. They felt untouchable and safe,” she wrote.

“IVF was an amazing choice for us to be able to make. So hard, but we got two beautiful monsters out of it. I promise you, I never ever ever ever ever thought I could,” she added.

As for how her kids are taking the news, Teigen revealed that they’re not on the same page.

“Luna is very, very excited,” she wrote. “Miles, not so much. Jealous!”

RELATED VIDEO: John Legend and Chrissy Teigen Are Expecting Their Third Child

Multiple sources confirmed to PEOPLE on Thursday that Teigen is expecting after the couple hinted at the pregnancy in Legend's latest music video, "Wild."

At the end of the romantic video, which also features the parents enjoying family time with Luna and Miles on the beach, they stand together in front of the waves as Teigen puts her hands on her stomach, revealing a tiny baby bump.

Hours later, Teigen showed off her growing baby bump on her Instagram Stories and Twitter.

"Look at this third baby s—," Teigen says in the video, posing in front of the mirror in a pair of black leggings and an open blazer. "What the ... oh my God."

During a live chat on YouTube ahead of the video's premiere, the couple also spoke about how special it is to be able to watch their relationship evolve throughout the course of Legend's music videos — which began with “Stereo,” where they first met on set.

“We have 'All of Me,' the marriage, no kids yet. 'Love Me Now' with Luna and this one with Miles,” Teigen explained, as Legend added, "It's been chronicling our family's growth and our journey and we're so happy that this video is the next chapter."