Jwoww, who is currently six months pregnant, explained via her official website that she was phoned at home by her physician as he'd noticed something on her latest ultrasound picture.
Quoting her doctor, the reality star said it was suspected that her unborn daughter had a "small cyst on her brain" and needed a specialist to take a look.
Jwoww phoned her fiancé Roger Mathews as soon as she heard the news, saying: "I don't think he even understood one thing I said. Literally hysterical to the point where I was hyperventilating thinking omg I did something so horrible to my daughter?"
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.
Reflecting on how she felt after hearing the news, Jwoww said: "Honestly I was happy but still my heart felt heavy. And even though I know I did nothing to cause it I felt guilty and so helpless. Such a horrible feeling…."
Thankfully, a relieved Jenni told fans that the cyst did disappear, as the doctor had predicted, and her daughter is fine.
That wasn't the only medical issue the star has faced in her pregnancy – during an examination it was determined she has a low-lying placenta which led her doctor to caution against sex for a month.
"I literally burst out laughing hysterically," said Jenni, joking that her fiancé reckons she paid her doctor to say that.
But assuring fans all is now fine, she concluded: "My daughter's cyst went away. Also my placenta is higher so I'm now longer at risk (don't tell Roger)."
Jwoww announced her pregnancy on Christmas Day. She became engaged to Roger in September 2012 after he popped the question while they were skydiving. (Really!)
The couple walked the red carpet at the MTV Movie Awards 2014 over the weekend, where Jwoww looked happy and healthy in a black dress.
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