Mid and West AM Simon Thomas welcomed campaigners aiming to keep services at Withybush Hospital, Haverfordwest, Pembrokeshire.
Plaid Cymru AM Simon Thomas spoke to the crowd outside the Senedd. According to the police there were 700 protestors.
The Party of Wales AM said: “I want to thank campaigners on their successful rally outside the Senedd. I will continue to work for fair services across the region.
“We will have to fight for a future for the Accident and Emergency department.”
“The people of my Mid and West region deserve the same health care as those in large towns and cities. Plaid Cymru’s policy is to recruit 1000 doctors to bring Wales up to European standards and enable services to be as local as possible.
“We deplore the Labour government’s decision to remove consultant-led maternity services from Withybush and Bronglais hospitals, which causes concern for parents and undermines accident and emergency cover in Pembrokeshire and Ceredigion.
“As Plaid Cymru AMs in the National Assembly we have opposed this decision in every way possible.”