Aug. 4, 2008 -- Schizophrenic women who get an estrogen patch along with their regular antipsychotic medications have fewer symptoms than women who get inactive placebo patches.

The finding, from a four-week study of 102 women of childbearing age with schizophrenia, comes from Jayashri Kulkarni, MBBS, PhD, and colleagues at Monash University in Melbourne, Australia.

During her psychiatric training, Kulkarni spoke with many schizophrenic women who kept telling her, "It's my hormones, Doc." They also told her, "No one takes any notice when I say that it's to do with my hormones."

Kulkarni took notice. She and her colleagues have now completed a series of small studies showing that estrogen can be very effective in reducing symptoms such as delusions, hallucinations, and disordered thinking.

"We are proud of the science, but the best thing is seeing the great improvement in our patients' quality of life," Kulkarni tells WebMD via email. "One woman who had been a nurse, developed schizophrenia soon after she had a baby and had the worst form of the illness. For eight years, she was more in hospital than out. She made a dramatic improvement on estrogen -- and went from being unable to even attend to her personal hygiene, constant auditory hallucinations, and paranoia to now being able to work as a clerical assistant and live independently."

Kulkarni is quick to add that one patient's experience does not prove the treatment will work for others. But she's seen rapid improvement in other women who were resistant to standard treatment, particularly those who developed schizophrenia just after having a child.

Several lines of evidence point to a major role for estrogen in schizophrenia:

The female sex hormone estrogen has important effects on chemical signals in the brain. These signals go haywire in schizophrenia.

Women's first episodes of schizophrenia occur later in life than men's, suggesting a protective role for estrogen.

In women, schizophrenia symptoms often appear just after childbirth and during menopause, when estrogen levels plunge.

Women with schizophrenia often relapse during the low-estrogen phase of their menstrual cycles.

And women with schizophrenia tend to have better outcomes than men do, notes Dost Ongur, MD, PhD, clinical director of the schizophrenia and bipolar disorder program at McLean Hospital in Belmont, Mass.