Australian scientists are taking a novel approach in treating women with schizophrenia. They have just published the findings of a clinical trial using the female hormone oestrogen.

The link between women's hormones and their moods is well known.

Life cycle studies have shown that women are more vulnerable to a first episode of serious mental illnesses such as schizophrenia at times of hormonal changes, such as post-pregnancy or menopause.

There is also some evidence from animal studies that the female hormone oestrogen acts as an anti-psychotic.

Professor Jayashri Kulkarni from the Alfred Hospital and Monash University in Melbourne wanted to see what effect oestrogen had on women with schizophrenia.

One hundred and two women were given a patch of either active hormone or a placebo. Participants were not told what they were using. They took their other anti-psychotic medications during the trial.

Researchers said those on the hormone treatment had their symptoms significantly reduced.

"The women who received the oestrogen made a really good recovery from their auditory hallucinations, that's hearing voices or from their delusional beliefs, that's like they were being followed or other beliefs that weren't true in reality," Professor Jayashri Kulkarni said.

Anna Thomas took part in the trial and said the treatment made a big difference. "I noticed a significant improvement in my clarity of thought ... that I hadn't had since I was 13 or 14 ... and that was prior to my diagnosis and illness of schizophrenia," she said.

Patients reported some minor side effects like breast tenderness and bloating. Women were also given mammograms, because of the link with high oestrogen levels and breast cancer.

Researchers are hopeful that the treatment could also be used on men in the future. They are hoping to trial newer forms of oestrogen which act on the brain and do not have the same side effects as traditional female hormones.

The study was published in the Archives of General Psychiatry.