A new £4m unit where women with serious mental health problems will be able to keep their babies with them ends a "postcode lottery", a doctor has said.
The Kingfisher Mother and Baby Unit at Hellesdon Hospital, near Norwich, will officially open on Monday.
Consultant psychiatrist Zeyn Green-Thompson said new and expectant mothers sometimes had to travel more than a hundred miles for treatment.
Mother Naomi Farrow said women must seek the help they need.
Ms Farrow, from Norfolk, suffered post-natal depression after her twins' births and set up a charity, Get Me Out The Four Walls, which is now working with the new unit.
She said: "I walked into my bedroom and sank to my knees and thought 'what on earth have I done'.
"I composed myself and went back to my three-year-old who was trying to put the dummies back in the twins' mouths.
"It was at the point that I wasn't being the best mum I thought I was being and needed help."
The eight beds in the unit, which is in the grounds of Hellesdon Hospital, are for patients from Cambridgeshire, Norfolk and Suffolk.
The Norfolk and Suffolk Mental Health Trust-run centre will treat women with illnesses such as postnatal depression, severe anxiety and postpartum psychosis - a condition causing hallucinations and delusions in women who have just given birth.
The trust said it had often faced a "conundrum" of women not wanting to leave their babies, but who were not well enough to remain at home.
Dr Green-Thompson said: "We know women suffering from ill health in late pregnancy or with young children were reluctant to separate from their families and travel to London, Birmingham or further afield.
"Obviating the postcode lottery and having a high quality in-patient service locally means all the difference."