The MTV reality star posted a picture to Instagram over the weekend, showing her adorable puppy Bonnie resting against her growing bump.
Maci, 23, confirmed her pregnancy just before the New Year, but this is the first time she's posted an image of her bump to social media.
It will be her first child with boyfriend Taylor McKinney, and she told InTouch Weekly the pregnancy had been a shock because she'd been diagnosed with polycystic ovary syndrome after the birth of her first child and warned conceiving could be difficult.
"We still can't believe it. It was a huge shock but we are very excited," she said.
Maci found fame in the MTV series 16 & Pregnant and its spinoff Teen Mom , which documented her teenage pregnancy with son Bentley and life as a young mum. Bentley's dad is her ex-boyfriend Ryan Edwards.
The starlet also had her own MTV special, Being Maci.
Maci had a difficult start to the year, becoming involved in a car crash in mid-January. She'd been travelling with six-year-old son Bentley when their Jeep flipped on the road and did three rolls.
Thankfully, she, Bentley and the unborn baby were not hurt.
She said at the time: "Thanking God that Bentley and I were able to walk away from this nightmare with only a few bruises. Thanking God that my unborn baby girl is perfectly healthy after this."
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