Campaigners say they are expecting hundreds of people to turn out to protest against possible changes to services at the Princess of Wales Hospital in Bridgend.
A consultation is currently underway over a reorganisation of health services across south Wales. The protest group 'Save Our Services' say they that they are concerned about the potential changes including a proposal to downgrade the full Accident & Emergency Unit and the Special Care Baby Unit.
Health service bosses say that the changes are essential to ensure that hospital care meets UK-wide professional standards and to deal with issues such as a shortage of doctors and increasing demand.
More top news
Seven professional rugby players had to be rescued when they got stuck in a hotel lift - because they broke the weight limit.
Wales has fallen silent to mark the 50th anniversary of the Aberfan disaster, which cost the lives of 116 schoolchildren.
Philip Thomas was a 10-year-old pupil at Pantglas Junior School in Aberfan when a coal tip collapsed and slid downhill.