Desiree Hartsock and her husband, Chris Siegfried, are expecting their first child together.

The 30-year-old formerBachelorette star shared the big news with her fans on Instagram on Wednesday, posting a cute picture of Siegfried pointing to her growing baby bump.

"We have a bun in the oven and it's not the warm pastry kind!" Hartsock joked. "We are beyond excited to share that we have a little one on the way!! A new chapter we are both looking forward to."

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She also dropped a hint as to when their little one is due, hashtagging the pic, "#october."

Hartsock starred in season nine of The Bachelorette, which ended with her getting engaged to Siegfried, a mortgage broker, on the season finale. More than a year later, they were married on Jan. 18, 2015. The couple celebrated their one-year anniversary in Maui.

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