Katharina Dalton, who has died aged 87, put the treatment of premenstrual syndrome (PMS) - the connection between the hormonal changes of the menstrual cycle with emotional mood swings - on the medical map.
She had first studied the syndrome while a GP in north London, and later ran the world's first PMS clinic. She also had her own consulting rooms adjacent to Harley Street. She wrote extensively on the subject, and acted as an expert witness in many high-profile criminal cases.
Katharina Kuipers, known as Kittie, was born in London to a Dutch businessman and his wife who had come to England to launch a branch of his stockbroking company. He died while his daughter was still young and, as he had been a freemason, she was educated at the Royal Masonic school. She then trained in chiropody, winning a scholarship to the London foot hospital. She practised for 12 years, and wrote Essential Chiropody For Students (1959).
Dalton had always wanted to be a doctor, and went to the Royal Free hospital medical school, qualifying on July 7 1948, the day the national health service started. She went into general practice in Wood Green, north London, and later in Edmonton. Within months, she noticed that her women patients had symptoms that coincided with their menstrual cycles; indeed, the idea that there was such a thing as premenstrual syndrome had only recently been aired.
Dalton contacted Sir Raymond Greene, one of her former teachers, and, in 1952, they published the first paper on it. This led to pioneering work on the effects of PMS on schoolwork, accidents, crime, psychiatric illness and behaviour. Dalton even showed that men suffered from their wives' PMT - salesmen, for example, achieved fewer sales while their wives were premenstrual.
She produced more than a hundred articles and research papers on PMS, postnatal depression, the importance of steady blood sugar levels and the dangers of vitamin B6 overdose (B6 is a treatment for PMS). In addition, she wrote nine popular and semi-scholarly books, in cluding one on her medicolegal work; they were translated into 17 languages and several are still in print.
In 1957, Dalton started the world's first PMS clinic, at University College hospital, London, which she ran for 40 years, unpaid. From 1964, she took rooms in Wimpole Street, where she saw private patients. She gradually spent more time there, and eventually gave up her GP work.
Her treatment for PMS consisted of recommending a good diet: sugar or starch every three hours - so that patients did not suffer from low blood sugar - and lots of fruit and vegetables. If that did not work, patients were treated with natural (not synthetic) progesterone. At one time there was a long waiting list, and patients were sent dietary advice; half of them subsequently cancelled their appointments, saying the diet had worked.
Dalton was often approached by lawyers defending women accused of crimes. She always insisted that she could not act as an expert witness on their behalf unless their symptoms were repetitive, cyclical and responded to treatment. She turned down many cases that failed to meet these criteria, including that of a murderer who claimed that he was tipped over the brink by his wife's PMS.
There were two famous cases in which her evidence was part of a successful defence: that of Anna Reynolds, who killed her mother while suffering from postnatal illness, and Nicola Owen, an arsonist who set fire to homes in Richmond and Twickenham, in south-west London, at intervals that were multiples of 28 days.
Professional opinion was always divided about Dalton, who was outspoken and worked largely on her own. There were those who recognised that she had developed the use of menstrual charts for PMS, the use of progesterone to treat it, and had done more trials and written more on it than anyone else.
On the other hand, there were those who felt that PMS is a condition with a huge psychosomatic element, and rejected Dalton as a fringe celebrity. On a scientific level, many believed that her diagnosis was sound, while her views on treatment were not. Fasting does not cause low blood sugar, and natural progesterone is immediately inactivated by the liver.
Dalton retired in 2000, aged 84, and moved to Hereford, and then Dorset.
Her first husband, Wilfred Thompson, with whom she had a son, was killed in action in 1942; her second husband, Tom Dalton, whom she married in 1944, and with whom she had another son and two daughters, died in 1994. Her children survive her.
· Katharina Dorothea Dalton, doctor, born November 11 1916; died September 17 2004
