Protesors are to hold a vigil outside Dewsbury District Hospital as a downgrade of the hospital begins this weekend.
Consultant led maternity services at the hospital, for women expecting complex and risky births, will cease between September 16 and 19.
The closure of these services will be followed by the closure of Dewsbury District Hospital’s A&E next year.
The vigil will take place at the Halifax Road entrance of the hospital on Friday from 11am to noon.
It has been organised by North Kirklees NHS Support Group.
Christine Hyde, of the campaign group, said: “To mark the first day of the changes – because we still do not think they are sensible – we are holding a vigil for an hour and we hope people will join us.”
Consultant-led maternity services will be centralised at Pinderfields Hospital in Wakefield before emergency care is centralised at the Wakefield hospital in spring 2017.
A spokesman for Mid Yorkshire Hospitals Trust, which runs Dewsbury, Pinderfields and Pontefract hospitals, said: “The changes will take place between September 16 and 19.
“Routine ante-natal and post-natal care, including scans, will still be offered locally in the community and at all three of the trust’s hospitals.
“There will be access to scans and assessment at Dewsbury for some women with complications in early pregnancy
“A dedicated acute gynaecology and early pregnancy assessment service will be set up at Pinderfields.”
Children’s inpatient services and acute surgery will also be centralised at Pinderfields.
If the Right Care Right Time Right Place plan, which would close Huddersfield’s A&E, goes ahead this would leave Kirklees without an emergency department.
A unit for patients with urgent – but not emergency – needs will open at Dewsbury. A similar unit is planned for a new hospital to replace Huddersfield Royal Infirmary.
A spokesman for Mid Yorkshire Hospitals Trust said: “Most complex surgery and surgery for people who may need critical care support will be centralised at Pinderfields.
“Changes to acute medicine and critical care services are due to take place in spring 2017.”
