Lincoln Maternity Hospital and Burwood Birthing Unit have been closed until further notice.
Canterbury District Health Board told women intending to birth at the units prior to the earthquake to go Christchurch Women's Hospital and staff there have been advised to expect more women.
The board said numbers attending Christchurch Hospital have been steady and the facility is functioning well and is fully staffed.
It said people presenting to the Emergency Department as a result of the earthquake have had mainly minor injuries but the number of cardiology admissions to the hospital is higher than normal.
Christchurch's after hours surgeries are reporting a steady numbers of patients but that they are coping well.
Local social workers have activated their emergency response team and are working with patients.
Damage done to Canterbury's hospitals by the earthquake is still being assessed.
The water supply has been restored at Burwood Hospital and is running as usual at Christchurch Hospital but extra water is being supplied for patients and staff at Hillmorton and The Princess Margaret Hospitals.
Christchurch and Burwood Hospitals are no longer using generators for electricity and Hillmorton and The Princess Margaret Hospitals have been told that the main power supply will be running again in the next few hours.
Health issues relating to water and sewerage are now the most pressing.
Earlier a spokesman said Christchurch Hospital was flat out this morning, inundated with injured people. He described the scene at the hospital as absolute chaos, however injuries were mostly minor.
Members of the public were urged not to come into hospital unless it is an emergency.
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