The reality star and fiancé Roger Mathews welcomed their first child together on Sunday, 13 July.
She weighed 7lbs 13oz.
A rep for Jwoww confirmed the happy baby news in a statement, saying: "Jenni and Roger are so excited to welcome the newest guidette Meilani Alexandra Mathews to the world.
"Meilani and her parents are doing great and are happy and healthy."
In a nod to the tot's super fit parents, the rep added: "Meilani is already looking to trade her baby bottle for barbells!"
Roger added on Twitter: "She is here! Meilani Alexandra Mathews 7lbs 13 ounces. Words can't describe what looking into your child's eyes can do to you. I'm humbled."
Jwoww and Roger announced the pregnancy on Christmas Day.
It wasn't the easiest of pregnancies as Jwoww revealed doctors initially suspected her unborn daughter to have a small cyst on her brain.
According to JWoww, the specialist said the issue – called a choroid plexus cyst - was something that happened in every one to two per cent of pregnancies, and would likely disappear by itself, which thankfully it did.
Jwoww and Roger became engaged in September 2012 after Roger proposed while they were skydiving.
Stars who welcomed babies in 2014 in pictures!
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