The two are already the parents of 6-year-old daughter Luna and son Miles, 4. The Chrissy's Court star noted in February that she was undergoing in vitro fertilization, which she underwent with her pregnancies of both Miles and Luna.
"The last few years have been a blur of emotions to say the least, but joy has filled our home and hearts again," Teigen wrote while breaking the happy news on social media. "1 billion shots later (in the leg lately, as u can see!) we have another on the way. Every appointment I've said to myself, 'ok if it's healthy today I'll announce' but then I breathe a sigh of relief to hear a heartbeat and decide I'm just too nervous still. I don't think I’ll ever walk out of an appointment with more excitement than nerves but so far, everything is perfect and beautiful and I'm feeling hopeful and amazing. Ok phew it's been very hard keeping this in for so long!"
Legend, who married Teigen in Sep. 2013, reposted the message.
"I asked the nurses to show me his hands and feet and I kissed them over and over and over again," Teigen recalled of the moments after she gave birth. "I have no idea when I stopped. It could have been 10 minutes or an hour."
In March the "Honey" singer told People that Luna and Miles were already "excited" about the possibility of a new sibling.
He also explained why he and Teigen had been so open about their experience.
"There are a lot of women and families that have fertility struggles, and I think no one should feel ashamed of needing some help sometimes. And I think Chrissy's done a good job of destigmatizing some of these things that so many people go through in silence," he said. "Whether it's IVF, or other fertility struggles, whether it's losing a pregnancy, I think both of us have felt like it's good for us to share this with other people because other people are going through it too, we don't think they should suffer in silence without knowing there are other people out there who are feeling the same thing."