The 25-year-old television personality confirmed Saturday on Twitter that she gave birth to a baby boy.
"Mother of boys," Lowry wrote, adding a blue heart emoji, after sharing an article about her son's arrival.
"I still don't have a baby name," she added the next day.
Radar Online reported Lowry welcomed her baby boy at 3 a.m. Saturday. The reality star had announced her pregnancy in February, and later confirmed Chris Lopez is her baby's father.
"I think I'm most worried about the changes ahead but also that I will have this baby 24/7 by myself with no help. I'm going to be a single parent from the beginning!" she wrote in a since-deleted blog post in April.
Lowry already shares 7-year-old son Isaac with ex-boyfriend Jo Rivera and 3-year-old son Lincoln with ex-husband Javi Marroquin.
She told Rivera on the July 31 episode of "Teen Mom 2" that her third pregnancy came as a surprise.
"I was told I couldn't any more children," the star said, according to People. "I was told I would have to go through fertility treatments and IVF and all kinds of things."
"It was not planned and not prevented," she said. "[Chris] knew I wanted a baby and if it happened, it was fine."
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