AceShowbiz -

Chrissy Teigen may look amazing in her recent Sports Illustrated swimsuit photos, but she was actually having some less convenient moments behind the scenes. While attending the SI Swimsuit "Swim Beach" fan event in Miami on Wednesday, February 17, the mother-to-be told PEOPLE that she was undergoing In Vitro Fertilization (IVF) treatment during the photoshoot.

"I was doing IVF during the shoot," the "Lip Sync Battle" commentator said. "I was getting my shots and everything in Zanzibar, I had a little medical kit. It was hard because you bloat from it, and you bruise - if I hit the wrong area. That's the kind of things we had to cover with makeup," Teigen added.

Previously, John Legend's wife revealed that she also struggled during a big Bruce Weber shoot. She said that she didn't look good at the time because her face was expanded due to constant hormones she received during the IVF treatment.

"And I was not looking my best. My face is full because of all the hormones I'm pumped with," Teigen recalled. "And to see every day that I'm getting crap for gaining weight or for having cheek fillers or for looking Botoxed because my face has just been expanded so much by these constant hormones..."

The 30-year-old model recently uploaded some of the SI photos on Instagram. In one of the photos, she credited everyone who assisted her during the photoshoot.