Pregnant women in Victoria's second-largest city will have to find a new hospital after Epworth HealthCare confirmed plans to close its maternity service in Geelong.

The decision came after the hospital in November announced a proposal to close the unit, citing staff shortages in nursing and midwifery.

"I'm extremely saddened by having to share this news with you ... I'm devastated," Epworth executive general manager Leonie Lloyd told hospital staff, executives and corporate representatives on Thursday.

The unit will close at the end of March, a month later than anticipated, and women booked in after then will be asked to find another provider.

About 100 women are booked to have their baby at Epworth Geelong after March 31.

"We are very aware that this will be a challenging time for each of these women, and their families, and we are committed to supporting them through this period," Epworth said in a statement.

Greater Geelong, Victoria's second-largest city, has a population of 274,647 and is forecast to grow to 393,216 by 2041.

"We have lots of patients wanting to come our way but we just do not have a safe staffing level to be able to support that group of women and their families into the future," Ms Lloyd said.

In January, Liberal senator Sarah Henderson referred Epworth HealthCare to the Australian Competition and Consumer Commission over the proposed closure.

"Epworth HealthCare has to date failed to respond to a wide range of proposed solutions which evidences that its consultation phase is nothing more than a sham," Senator Henderson wrote to the ACCC.

Epworth Group interim chief executive Cameron Fuller said all feedback had been carefully considered in the two-month consultation.

Mr Fuller said Epworth Geelong currently had 14 full-time equivalent roles available across its maternity service, a vacancy rate of 44 per cent.

"We would like to acknowledge and thank our existing Epworth Geelong midwifery staff who have reached out during this time to express interest in increasing their hours or moving to our permanent roster," Mr Fuller said.

"Even with these potential additions, we would still have a 35 per cent vacancy."

The Australian Nursing and Midwifery Federation's Victorian branch said the decision represented a missed opportunity to build and invest in the hospital's midwifery workforce.

"Epworth Geelong is competing in a tight midwifery workforce market, but has displayed little initiative in investing in its midwifery workforce," ANMF acting secretary Paul Gilbert said in a statement.

The union said it would continue to support its members until the service closed, including negotiating redundancies and helping to find other work.