The Royal College of Midwives says the need for a maternity strategy in Northern Ireland has gone beyond urgent and is now critical.
The warning comes as the RCM is publishing a report on Northern Ireland's maternity services at Stormont on Tuesday.
The report will highlight growing challenges as more women across the country with additional health needs are being cared for by maternity services.
The RCM report being launched on Tuesday outlines three steps to deliver high quality and safe services for women and families.
-Develop, publish and fund the implementation of a new maternity and neonatal strategy for Northern Ireland.
-Sustain the number of places for new student midwives at their recent, higher level.
-Focus on retaining the midwives in the HSC.
There are an increasing amount of women who are being cared for by maternity services in Northern Ireland with additional health needs.
More than 25% of pregnant women in Northern Ireland are obese and less than half have a weight within a healthy range.
Women are also getting pregnant later in life, with a rise in pregnancies in those over 30.
All of these factors have put increased pressure on maternity services despite a falling birthrate across the country in recent years.
RCM Director for Northern Ireland, Karen Murray, said: “Services are coping because of the incredible efforts of staff, who go above and beyond on a daily basis, often to the detriment of their mental and physical health, but this is not sustainable.
"We are seeing far more complicated pregnancies, and this is increasing the demands on midwives and their colleagues.
"They want to ensure these women get the best possible support, advice and care. That is proving more and more difficult without the resources to back them up.
"We need more investment and more midwives to deliver the services women expect and deserve."
Karen Murray continued: “The recent rise in the number of student midwives is one thing we are getting right – and one that must be sustained.
"Any fall in student midwife numbers will have a negative impact on the care for women and the wellbeing of staff.
"It is also essential that we focus on retaining the midwives that we have by ensuring that they are paid fairly and have opportunities to work in sustainable ways and to develop their career.”
Ms. Murray added: “Increasingly, and quite rightly, women have higher expectations of maternity services than in generations past.
"The needs and health of women using maternity services is changing rapidly and we need a new maternity and neonatal strategy, which has recruitment and retention at its heart.
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