The service's popularity is growing as women choose a low-intervention, midwifery-led "normal" birth for better long-term outcomes for mother and baby.

ACT Health plans to review the program to expand access at both the Centenary Hospital and Calvary.

Both hospitals offer the natural or "normal" birth options in the form of a continuity of care model. The program sees pregnant women paired with a midwife for the duration of the pregnancy and for a short time after birth.

Data from ACT Health shows the proportion of women giveing birth at a birth centre in the ACT increased from 6.2 per cent in 2011 to 8.3 per cent in 2015.

The number of babies born at a birth centre remains a small proportion of total births in the ACT.

In 2015 91.7 per cent of births were in hospitals (5775 babies compared to 523 in the birth centres).

Despite recent complaints about maternity services at Canberra Hospital, an ACT Health spokesman said for women who access the birth centre, "there is a high level of patient satisfaction".

Ms Fox is due to give birth in August to her second child. The same midwife who cared for her during her first pregnancy is now watching over her second.

"I wanted to have an experience that was as home-like as possible, with the continuity of care model that promoted as little intervention as possible," she said.

"The birth centre and midwifery program provided those things."

Ms Fox said having the same midwife a second time made it even more special.

"We already have a relationship, and it just makes it a little less stressful. You have that one person who knows you, and that's really comforting."

Ms Fox said she heard about the program the first time through word-of-mouth, and knew to book in straight away so she wouldn't miss out.

"I called the day I did a pregnancy test and booked in, and I was still on the waiting list for a couple of weeks this time before I got in."

Midwife Helen Blake has worked at the Canberra Hospital for 35 years as both a nurse and a midwife. She said she's "extremely proud" of the care that they provide.

"We have beautiful facilities here, and the care we provide, giving them choice around their place of birth, is really important to them," Ms Blake said.

Ingrid McKenzie, another midwife with the service, is relatively new to the profession with about three years under her belt.

"I started more recently but it's this model that I always wanted to work in," Ms McKenzie said.

"What's great is building that relationship with women, and that's what makes the continuity of care model so successful and it's why there are better birth outcomes for women and babies.

"The way the birth process works is that if the women is feeling relaxed, comfortable and trusting of those around her, the better she labours. That's the way the labour hormones work.

"In a lot of ways, it's a very safe model as well. I know all of her conditions that everybody needs to know about that might come up during the birth. It means that there's less likelihood of things getting missed if one person is knowing everything."

Ms McKenzie supported Kirbie and Andrew Barrell for the birth of their daughter Isabel on April 19. Isabel is the family's second child, after two-year-old Finn.

Ms McKenzie was on a rostered day off on the day Isabel decided to enter the world, but another midwife who works in the team assisted instead.

"Ingrid was back on at 7am the next morning but I said I just don't think we can keep it in for that long," Mr Barrell joked.

Mrs Barrell said the midwives had done a handover so the second midwife knew everything she needed to about the situation.

"I found that throughout the labour every suggestion the midwife made was just perfect timing and it really helped having that expertise," Mrs Barrell said.

Like Ms Fox, Mrs Barrell called the birth centre on the day she found out she was pregnant.

"I put my name down, I think it was the second call that I made," she said.

"In terms of the birth, it's just really nice to be trying to do things as naturally as possible, that was my goal."

Mrs Barrell said she liked not having to have a birth plan, because everything she wanted - things like not to be offered drugs, to be able to labour at home - was part of the philosophy of the birth centre.

She said she didn't want a repeat of her son's traumatic birth two years prior.

"I was able to labour at home and have her here within an hour and a half of arriving. It was very empowering and beautiful," she said.

About 30 per cent of women who give birth at the Centenary Hospital access the continuity of care model, but only half that number end up giving birth in the birth centre.

Centenary Hospital for Women and Children director of nursing and midwifery Karen Faichney said the women who don't end up birthing in the birth centre have developed complications either during pregnancy or birth.

"They will keep their midwife but give birth in the birth suite," Ms Faichney said.

She said there was a waiting list for the midwifery program. She said demand far outstriped resources and the plan was to build the program to allow more women to be involved.

"The birth centre's service is for low-risk women. Only women with no risk factors in their pregnancy and no risk factors developing during their labour are able to birth in the centre because it is a midwifery-led service and it's focused on normal birth," Ms Faichney said.

Women who give birth at the birth centre can access pain relief during labour but primarily use non-medical forms of pain relief, like water.

She said research showed continuity programs led to better outcomes for everyone.

"With continuity of care you're more likely to notice when there are even subtle changes during pregnancy. The other thing we know is that by developing that relationship with that women, the midwife is able to really help her with the choices she wants to make in relation to her labour and help empower her to really have the sort of labour she wishes for."

"What it comes down to is that birthing is a natural process. It's a natural part of life. Being pregnant isn't an illness.

"We focus very much on the natural process and empowering women to birth the way women are engineered to birth, and for that to be as joyful and natural experience as possible."