Hollywood actress Kate Winslet has given birth to a healthy baby boy.

The 38-year-old welcomed her 9lb bundle of joy, her third child but her first with husband Ned Rocknroll, at an NHS Hospital in Sussex.

"Kate had Baby Boy Winslet on Saturday at an NHS Hospital. Mother and baby are doing great," her spokeswoman said. No other details were made available.

The Titanic star has a daughter, Mia, from her first marriage, to Jim Threapleton, and son Joe from her second marriage, to Sam Mendes.

Winslet and Rocknroll tied the knot in a secret ceremony aftert two years of dating.

Rocknroll was born Ned Abel Smith but changed his name by deed poll. The 35-year-old is the nephew of Virgin boss Richard Branson and works on the space-travel branch of the Virgin empire.

Although it is not known which surname the proud parents will give their newborn son, Winslet previously said she had no plans to change her surname

"I was never going to change my name to Rocknroll. I've never changed my name to anything so I didn't see a reason to start now," she told Us magazine.

Earlier this year she discussed plans to add to her family.

"I'm hoping to have more kids," she said. "I don't know whether one or two. Oh, God, I would love to have more.

"I feel great. Being a parent turns you inside out. It completely transforms your life and, of course, your children are your absolute everything."