Kelly Clarkson has "really bad" morning sickness.

Kelly Clarkson

Kelly Clarkson

The 33-year-old singer, who is expecting her second child with music manager husband Brandon Blackstock, admits she regularly has to seek medical attention because she gets "so dehydrated" from vomiting "all day."

The 'Stronger' hitmaker told 'CBS This Morning': "I'm familiar with all-day sickness. I have to get IVs and fluids because I get so dehydrated. It's really bad."

The former 'American Idol' star also threw up a "dozen times a day" when she was pregnant with her 17-month-old daughter, River Rose.

Kelly spontaneously announced her second pregnancy while performing her track 'Piece By Piece,' which is about her estranged father, at the Staples Centre in Los Angeles in August after she was overcome with emotion mid-song.

She explained: "I couldn't get through it and I was crying so hard and I thought, 'These people are going to think I'm on drugs but I'm about to lose it like a crazy person.' I was like, 'oh I gotta explain.' And then it just came out."

Last month, she revealed she is expecting a baby boy by posting a photograph of River on Instagram, with the caption: "In other news, River's gonna have a little baby brother :) #itsaboy We're so excited!"

The 'Heartbeat Song' singer says Brandon is nothing like her own father.

She said: "Well, he was present. He wins for being around."