Ms Alarca, 26, says she had a history of anxiety and the unexpected stress of the birth "sparked that up".

By the time she fell pregnant with her second son, Jayden, the young mum felt she was on top of things.

But a visiting midwife decided she shouldn't face the daunting challenge of trying for a conventional birth, after her traumatic caesarean, alone.

Ms Alarca was enrolled in a NSW government program designed to prevent post natal depression in new mothers through intensive home visits.

With the support, the second birth was smoother. So Ms Alarca says she wasn't expecting her "negative headspace" to return - but it hit.

"All the stress and tiredness when he started crying, and was awake more, and my husband and support network had returned to work," she recalls.

But this time she had a social worker, who taught her thought processes and techniques to deal with her anxiety. A physiotherapist assisted Jayden when she had concerns about his foot, and a nutritionist was on hand.

A nurse continues to visit monthly, checking Jayden's milestones.

"There are a lot of different people on my side who can help," she says. "I am grateful. Without them I have no idea where I would be. There's no way I would have returned to work."

Ms Alarca, who lives in Hamlyn Terrace near Wyong, said it was important that the support came to her home.

"It takes the pressure off having to pack everyone up and get them through the door. When you are in that space it is debilitating and paralysing."

The Baird government will include $22.8 million in Tuesday's NSW budget to expand the Sustaining NSW Families program, which has run successfully for five years in Wyong, Maitland, Fairfield, Arncliffe and Ballina.

The Minister for Mental Health and Women, Pru Goward, said the program was being expanded to areas of Sydney with high birth rates: Canterbury, Auburn, Parramatta and Campbelltown.

Ms Goward said the program intervened early when young families were having problems "before something small becomes a crisis".

"Having a baby is the most wonderful thing but I know how scary it is... mothers worry about not having enough milk, whether their baby is growing as fast as other babies," she said.

It is important to "nip it in the bud" when these worries spill into a more serious anxiety.

"When I was having children we were told you all get depressed, it's the baby blues, it was dismissed a bit lightly. But for 15 per cent of mothers, we know, it's very scary and can go on for a long time."

Most women who suffer from postnatal depression have experienced anxiety and or depression in pregnancy.

Families with identified vulnerabilities will receive home visits by specially trained nurses supported by a range of health and psychosocial staff, from pregnancy until the child reaches two years of age.