Rob Kardashian's fiancee Blac Chyna has opened up about her second pregnancy, revealing it's going as smoothly as her first.

The model, who is mum to rapper Tyga's three-year-old son King Cairo, announced she is expecting a baby with Kim Kardashian's brother last month (May16), and she insists her first trimester has been a breeze so far.

"If you guys are wondering, I'm actually having a really good pregnancy similar to King's," she told her fans on Snapchat. "No morning sickness, no cravings - just baby."

Rob and Blac Chyna will be documenting their relationship and the pregnancy on their new docu-series, which is tentatively titled Rob & Chyna. The six-part project will air on the E! network later this year (16).

"Very few love stories have created as much pop culture buzz as Rob and Chyna's, and we are thrilled to see Rob in such a happy place," explains Jeff Olde, Executive Vice President of Original Programming & Development at E! "We are excited to share the next chapter in their relationship."

Rob and Chyna will also film a follow-up special once their child is born later this year (16).

"So I was just wondering are you guys super excited about the TV show I'm doing with Rob," Blac Chyna asked on Snapchat.

And dad-to-be Rob is thrilled about impending fatherhood, although he recently admitted he would like to keep his family life private - despite agreeing to allow the cameras to catch the countdown to baby.

"It's my first time, so everything is exciting, literally," Rob told E! News in early May (16), in his first on-camera interview in more than two years. "I'm happy and I just like to keep it, you know, keep it private... as private as can be."