Christchurch's St George's Hospital maternity unit is closing in June, at the end of its contract with Te Whatu Ora.
Midwives organised a petition backed by 30,000 people to try to stop the centre from closing last year.
Hospital chief executive Blair Roxborough said it had not been able to agree to a contract extension with the health agency.
"Today we have advised our maternity staff and the Midwives Union MERAS that we are sadly closing our maternity centre and disestablishing all maternity related roles."
The nationwide midwife shortage had meant the hospital had struggled to maintain consistent, safe staffing levels, Roxborough said.
"The national shortage of midwives leaves us very confident that all our staff will find new roles."
Te Whatu Ora hospital and specialist services national director Fionnagh Dougan acknowledged staffing levels and workforce constraints meant the service was not sustainable.
MERAS co-leader Jill Ovens also recognised the unit's critical staffing levels over the past few years, which she said had restricted the number of beds available and resulted in women being turned away.
"St George's maternity hasn't been providing a reliable service because of workforce pressures. There needs to be two midwives on each shift to be fully staffed and that has been a challenge."
While more than 6000 babies are born in Canterbury each year, only 10 births and 34 postnatal transfers on average each month have been taking place at the hospital's unit recently, according to Te Whatu Ora.
Most births and postnatal stays had been cared for at Te Whatu Ora's maternity service, Dougan said.
MERAS also said occupancy in the St George's Hospital maternity unit had reportedly dropped 41 percent in the past 12 months.
"Perhaps because of a lack of surety around beds being available, midwives have not been bringing women to St George's to birth," Ovens said.
Alternatives far from communities - midwives' union
But she said news of the unit's closure was sad and it would have been ideal to keep it open until Te Whatu Ora's new central city primary birthing unit was open, which was expected to be late this year.
St George's currently provided the only primary birthing unit in Christchurch, with the nearest alternative half an hour away, by car, Ovens said.
"There are other options but for Christchurch-based families, they are away from their community which is not ideal for women or midwives."
Ovens believed neither the hospital nor Te Whatu Ora should be blamed for the decision made on Monday, saying it was a result of ongoing workforce stresses combined with the slow recognition of midwives' skills and value.
"The issues are more broadly entrenched across the maternity and health sector, and Aotearoa is reaping what has been sown.
"Had those who can make the difference been courageous enough to sort multiple issues out when they were first apparent a decade ago, I don't think we would be in the challenging situation we are now."
Other options
The hospital was still open to providing other maternity related services and would be exploring its options, Roxborough said.
"We continue to support the Rotary Breast Milk Bank by providing it with a home at the hospital, free of charge."
Roxborough thanked all the midwives and clinicians who had helped deliver babies there over more than 90 years.
"We also want to thank whānau who have chosen to give birth at St George's - we know that St George's Maternity has been a special place for so many people."
Dougan also thanked the hospital's maternity unit for their service to the community.
"We hold a strong and valued relationship with the team at St George's Hospital and we look forward to continuing our partnership through their provision of some hospital and specialist services in the Canterbury region.
"We want to reassure whānau expecting the arrival of a baby in Christchurch that they will always receive the care and support that they need at this special time in their lives, whether that is through our primary birthing units in Rolleston and Rangiora or Christchurch Women's Hospital."
The new Oromairaki Maternity Unit at the Toka Hāpai (Selwyn Health Hub) opened last year.
Te Whatu Ora's new central city primary birthing unit (Kurawaka: Waipapa) is set to be more than double the size of the St George's unit, with four birthing rooms, 20 post-natal rooms, two whānau rooms, an education room and six assessment rooms.
RNZ
