The world's first test-tube baby, Louise Brown, has led the tributes to the pioneer of IVF, Professor Sir Robert Edwards, who has died aged 87.

Professor Edwards was knighted in 2011, five decades after he began experimenting with IVF.

His work led to the birth of Ms Brown at Oldham General Hospital in 1978. She said he had brought "happiness and joy" to millions of people.

IVF is used worldwide and has resulted in more than five million babies.

Prof Edwards died in his sleep after a long illness.

Ms Brown said she has always regarded Robert Edwards as being like a grandfather to her, and
she is glad that he lived long enough to be recognised with a Nobel prize for his work.