Historically, syphilis was extremely difficult to cure. Often patients would think that their disease had disappeared or been cured, only to have their bodies betray them with a resurgence of symptoms. This was the story outlined in Sunday night’s episode of Victoria – but aside from the obvious scientific questions about drugs and treatment regimes, it also raises points about the treatment of women.

In Victoria, things were finally looking up for Prince Ernest (David Oakes). He was responding well to treatment and, consequently, had been given the all-clear by his doctor to marry. Moreover, the Duke of Sutherland had considerately fallen off his horse, making Harriet (Margaret Clunie) a merry widow and prospective bride. But that was before a coppery rash appeared across Ernest’s splendid shoulders.

To a historian of medicine, this didn’t come as a great surprise. I’ve read hundreds of Victorian case notes on venereal-disease (VD) patients, and they often follow a dishearteningly familiar pattern. Having responded well to treatment, many relapsed several months or years later. Stigmatising infections, lengthy treatments and uncertain outcomes took an emotional toll on patients. Nineteenth-century doctors took seriously the notion that a diagnosis of syphilis could trigger acute despair and melancholia. Indeed, this was the subject of Arthur Conan Doyle’s short story Third Generation, which follows an aristocratic young man diagnosed with syphilis. Consumed by paranoia that his fiancee’s family will discover his secret, and fearing disgrace, he throws himself under a horse-drawn carriage.

Happily, such a fate has not befallen Ernest. But he’s nonetheless been dealt a terrible blow, all the more because he had believed himself cured. He also faces a moral dilemma familiar to many young Victorian men. Does he postpone his marriage to Harriet, thereby ruining their happiness? Or does he marry Harriet, thereby ruining their happiness? The first option, as Conan Doyle would have us believe, risks social ruin. The second has even more serious consequences. Ernest risks infecting her and any children they might have together.

As well as causing infertility, syphilis can induce miscarriages and stillbirths. Some children born to syphilitic mothers will never show any signs of infection. Others die in infancy or develop serious health complications. Today, routine antenatal screening in Britain catches most cases of syphilis among pregnant women. But in the 19th century, infection among wives and children was common across all social classes.

These domestic tragedies were often dealt with quietly. But occasionally they exploded into scandal, as in the very public breakdown in 1886 of the marriage of Gertrude Blood and Lord Colin Campbell. Unbeknown to Gertrude or her parents, Lord Colin was being treated for syphilis and knowingly infected her. The case became a cause célèbre as curious readers pored over salacious newspaper reports of the Campbell’s dysfunctional marriage. With the establishment of the divorce courts in 1858 women like Gertrude could theoretically extricate themselves from abusive marriages. But, whereas husbands needed only to prove adultery, wives needed additionally to prove either cruelty, desertion or bestiality. Able to demonstrate only cruelty through the wilful communication of syphilis, Gertrude had to settle for a judicial separation.

Women in Gertrude’s predicament contended with husbands who were protected by the medical and legal establishment. If a husband infected his wife with syphilis or gonorrhoea, a doctor went to great lengths, usually at the behest of the husband, to conceal the cause of her illness. She would know that she was ill, but she wouldn’t necessarily know that she had VD. Doctors who withheld information from women claimed that they were bound by patient confidentiality – a doctor couldn’t tell a wife that she was suffering from syphilis because doing so would reveal that her husband also had syphilis. A degree of pragmatic paternalism informed these decisions: doctors believed that they knew best and prioritised expediency. After all, a woman who discovered that she was infected with VD might cause a fuss and make her husband’s life difficult. And since the husband was usually the one paying the doctor’s fee, his interests took priority.

Moreover, in the minds of Victorian moralists, possessing knowledge of VD debased a woman. Ignorance was equated with innocence and purity. And the cost, all too often, was her health. Once the more obvious symptoms disappeared, a doctor might find himself compelled by the husband to terminate treatment lest the wife become suspicious. Certainly, not all women were victims of such negligence. The growing numbers of women doctors were especially willing to discuss diagnoses and treatments with their patients. Yet concealment was so common as to become the subject of fraught medical and social debate.

It’s tempting to condemn doctors for what we now consider to be the mistreatment of female patients. In our modern ethical framework, we prioritise the patient’s right to make decisions about their care and to be given the information needed to make those decisions. But other important factors informed 19th-century medical encounters. Victorian doctors were in a legal and professional bind. Disclosing information to their patients might at best result in dismissal from the case. At worst, they might be pursued through the courts for breaching confidentiality. Such inequalities are difficult to sustain in a nationalised health service, where doctors are not subject to market pressures. Indeed, the establishment of a state VD service during the interwar years helped to consolidate new types of healthcare protocols that resemble those of today. With a mandate to provide free, universal care, the VD clinics of the 1920s and 1930s helped to break down the economic power imbalances that had shaped Victorian doctor–patient relationships.

These changes were also the product of new debates over culpability and infection control. British medical authorities were preoccupied at mid-century with the idea that prostitutes were the primary carriers of infection. By the 1890s, however, public censure was shifting to the intemperate, affluent men who exploited working-class women and infected their own families. The threat posed to women like Harriet and Gertrude became the focus of a campaign spearheaded by the “New Woman” movement. Young, affluent and unchaperoned, the New Woman railed against sexual hypocrisy and demanded that women have knowledge of, and control over, their own bodies.

Syphilis was a capricious mistress and the Victorians were intolerant of those who crossed her path. Ernest may yet be cured, but if Harriet marries him before that happens, she could find herself in the same mess as Gertrude.

• Anne Hanley is a historian of medicine at Birkbeck, University of London and acted as a historical consultant on Victoria. For more about Victorian medicine, follow her on Twitter at @annerhanley.