INB / WENN 1 / 5

"Teen Mom" star Maci Bookout is about to have a new addition to her family and she's already calling it a "miracle."

The MTV star is expecting a baby girl with her boyfriend of two years, Taylor McKinney.

RELATED: Where are they now? "Teen Mom" and "Teen Mom 2"

"We still can't believe it!" Maci told In Touch. "It was a huge shock, but we are very excited. I'm due in June."

Maci already has a 6-year-old son, Bentley, but she was diagnosed with polycystic ovary syndrome (PCOS), which makes it difficult to get pregnant.

RELATED: Transformed reality TV stars

"This baby is such a blessing. I'm calling her my miracle baby," she said, adding that she wasn't exactly optimistic that she would be able to get pregnant again. "We were very concerned that we might not be able to have a child of our own, so we talked about adoption. I knew my chances [of getting pregnant] were very low."

RELATED: Most controversial reality TV stars

Bentley, Maci said, is also over the moon about the pregnancy. "He's already nicknamed the baby Bubby," she said.

As excited as the now 23-year-old reality-TV star is, she knows that raising a girl has one main drawback ...

"I'm not a big fan of pink stuff," Maci said.