Rob Kardashian and Blac Chyna are having a baby girl

Rob Kardashian and Blac Chyna attends Birthday Celebration And Unveiling Of Her Chymoji Emoji Collection at Hard Rock Cafe. Photo / Getty

Rob Kardashian and Blac Chyna have revealed they are expecting a girl but the news isn't exactly what Rob was hoping for.

The reality duo revealed the gender of the baby during the premiere of their show Rob & Chyna while at a doctors appointment, reported E news.

Rob Kardashian and model Blac Chyna attend the Sky Beach Club at the Tropicana Las Vegas. Photo / Getty

"I'm pretty nervous. I'm excited," Rob said has he awaited the news. "I really want a boy."

"You have a boy at home, right?" the doctor said, referring to Chyna's son King Cairo she had with her ex Tyga.

"Yeah, but I don't," Rob said.

"That's OK, this is your first," the doctor said.

"It's an emotional moment. Me wanting to have a boy, it definitely stems from my dad but I'm sure I'll have the same relationship that I had with my father with my daughter," Rob later said.

"I'm just happy that the baby's healthy and I'm gonna be super happy with a girl."

The girl is due in just a couple of months but the couple revealed earlier in a Facebook Live chat that they are unlikely to carry on the K name tradition.