Georgina Somerset, who has died aged 90, lived the first 34 years of her life as a man, having been wrongly registered at birth as a boy; a high-profile “intersexual” (a person born with both male and female characteristics), in 1962 she became the first known woman legally to marry in church after officially changing sex.

Her earliest recollections were of wanting to be a girl, although she had been brought up as George Turtle, the youngest son of a Surrey dentist. George grew up asexual, attended boys’ schools, went to college and joined the Navy in the dying days of the Second World War.

By the mid-1950s, practising as a dentist himself, Turtle had recognised himself as an intersexual and had started to develop breasts while being treated with oestrogen hormones. But in November 1957, while trying to live as a woman, he was dragged into a field and raped.

In 1960 Turtle’s birth certificate was finally corrected to show “him” as a girl named Georgina Carol Turtle. Two years later, she married Christopher Somerset, a design engineer, and settled at Hove, where she ran a busy dental practice until her retirement in 1985.

Georgina Somerset with her husband Christopher /Photo: REX

The youngest of three children, Georgina was born on March 23 1923 at Purley, Surrey, and christened George Edwin Turtle. Educated at Croydon High School for Boys and later Reigate Grammar School for Boys, he studied dentistry at King’s College Hospital in London, qualifying in 1944. After being called up as the war in Europe ended, he served as a pipe-smoking surgeon-lieutenant in the Royal Navy until 1948, at which point he established a dental practice in Croydon.

During the 1950s Turtle undertook a traumatic quest for medical and legal acceptance as a woman. As he put it in his book Over The Sex Border (1963), society’s attitude was that “one was either wholly male with a short back and sides, or wholly female”.

There were few aspects of his life that remained untouched by the rigid distinctions of the day: in 1945 his father, a prominent Freemason, had initiated both his sons into the Craft, but George felt compelled to resign from his Lodge in 1953 after being advanced to the rank of Worshipful Master.

Obstetricians of the 1920s worked mainly on the evidence of their own eyes, although Turtle believed that in his case there must have been some confusion, because his birth was registered outside the legal time limit. In the days before genetic tests and more rigorous development checks, what Turtle described as a “malformed penis” decided his sexual destiny.

His parents never referred to any possible confusion, and Turtle remembered longing to wear pink dresses and always regarded himself as a girl. He found ways to change for games out of sight of his schoolmates, and was accepted into the Navy after the most cursory of medical examinations.

After the war, however, while insisting that he had been neither homosexual nor effeminate, “I found it increasingly difficult to pretend to be the 'man’ that my upbringing demanded of me”. A psychiatrist who believed Turtle’s problem to be psychological, suggested electric shock treatment, but when Turtle turned to the leading sexologist of the day, he was told that he was physically a hermaphrodite, unable to function as a man and with dominant female characteristics.

Turtle was told what he had known all along: that biologically he was female, his body possessed female receptors, and that he needed oestrogen “like a baby needs milk”.

As a boy, a tiny, non-functioning testicle on one side had been removed, but the sexologist detected signs of a second, failed gonad on the other which, he warned, would almost certainly turn out to be an ovary. Later, during an appendectomy, Turtle was also found to have a rudimentary womb. The answer, he was told, was a sex change. After taking one look at Turtle, fresh from his dental surgery clad in black morning coat and pinstripe trousers, the eminent plastic surgeon Sir Harold Gillies waved him away, explaining later: “I do not really think you look or could be made to look like a woman.”

In January 1957, after minor corrective surgery performed by another consultant, Georgina Turtle finally felt she had become herself, leaving the clinic in her first outfit of women’s clothes. She moved to a rented bungalow near Bognor Regis to let her hair grow and to establish herself as a female.

But her rape ordeal the following November confined her to bed for several weeks with pneumonia and, after contemplating suicide, Turtle cut off her long hair and went back to living like a man; other men mocked her in the street (“Cor, Davy Crockett!”), and it was only when she retreated to a rented cottage at Plumpton, near Brighton, that she felt able to revert to a female persona.

Her father’s funeral in July 1959 posed a problem, since the rest of the family were expecting George, the youngest son, to be present; Georgina had her hair shorn again, her manicured nails trimmed, and went to the funeral wearing a man’s dark suit . After this she lived as a man again for a further nine months while her father’s affairs were wound up.

Early in 1960 Turtle sold her dental practice, leaving Croydon as a man and arriving at her new home in Hove as a woman; this time the metamorphosis was final and irrevocable and, after sworn medical testimony from her doctors and surgeons, she was issued with a corrected birth certificate that registered her as Georgina Carol Turtle (Carol after Carol White, the heroine of a Daily Mail strip cartoon of the day).

The sex-change of Gina Turtle, as she preferred to be called, caused a Fleet Street frenzy, as did her engagement, announced on the Court and Social page of The Daily Telegraph in June 1962.

At her wedding to Christopher Somerset at St Margaret’s, Westminster, in October, Gina asked her brother to give her away, then two uncles and finally her family doctor: all declined. Her Plumpton landlord stepped in, and what The People newspaper billed as the “strangest fashionable wedding on record” went ahead without a hitch.

Although re-registered as a woman, Gina Somerset was nearly 40 when a genetic test revealed a rare mosaic of chromosomes: a Y male chromosome (accounting for her deep contralto voice) coupled with the female chromosomal make-up of Turner’s syndrome, a disorder which, without oestrogen treatment, can stunt growth and lead to infertility and retarded breast development.

Georgina Somerset’s birth registration mistake returned to haunt her at the age of 60 when, on applying for her state pension, she was told that she would have to work another five years. For 30 years the social security authorities had never changed her status, but agreed to do so when it was pointed out that the applicant was now, legally, a woman.

She published a memoir, A Girl Called Georgina, in 1992 when she was 68, having lived for 34 years as a man and 34 as a woman, reporting that she was in better health than ever, even though she had taken no oestrogen for some 20 years.

She declared herself to be a regular size 12, weighing 130lb, 5ft 8in tall, slim, with a 34in bust, long slender fingers, brown eyes, blonde hair and a very fair complexion — on account, perhaps, of the fact that she had never shaved in her life, even as a man.

Her husband, Christopher Somerset, a distant kinsman of the Dukes of Beaufort, survives her.

Georgina Somerset, born March 23 1923, died November 30 2013

Telegraph