Henry VIII’s reign is often remembered for his many marriages and his relentless pursuit of a legitimate heir. While his marital antics have become the stuff of legend, less attention is paid to the potential medical reasons behind his inability to ensure the Tudor hold on power. Modern science suggests that Henry’s reproductive woes might not have been the fault of his wives as Henry often claimed. Instead, the early deaths of many of his children or their fetal demise may have been caused by the very genetics that made up King Henry VIII himself.
Failed Marriages Because of Missing Heirs

Henry VIII’s first two wives, Catherine of Aragon and Anne Boleyn, endured an unbelievable amount of pregnancies that ended without a healthy, living child for the realm. Between 1509 and 1519, Catherine had at least six pregnancies, only one of which resulted in a surviving child — Mary. Anne Boleyn’s record was even more tragic; during her 1,000-day reign, she had three known miscarriages out of four pregnancies between 1533 and 1536.
Among the rare children who did survive childbirth, Henry’s firstborn son, Prince Henry (born in 1511) lived for less than two months. Jane Seymour, Henry’s third wife, eventually gave birth to the long-desired male heir (an act which killed her) but she too experienced pregnancy complications, possibly suffering one or two miscarriages before Edward’s birth.
The recurrent miscarriages and infant deaths have led both historians and medical professionals to speculate about the role of underlying health issues in one or both of the parents. One theory that has gained some traction is that Henry’s wives, particularly Catherine and Anne, may have suffered from undetected anemia.
If an anemic woman becomes pregnant, her eggs may degrade over time, leading to non-viable pregnancies. This could prevent the proper division and growth of fetal cells, increasing the likelihood of miscarriage. Repeated miscarriages, in turn, could exacerbate the anemia, creating a vicious cycle of trying for a royal baby, getting pregnant, and then the pregnancy terminating before birth.

At least in his early years, Henry didn’t seem to struggle to get his wives with child. There is documentation suggesting that a couple of Henry’s marriages may have been hastened along due to evidence that his potential queens were already carrying his child. For instance, Jane Seymour’s swift marriage to Henry eleven days after Anne Boleyn’s execution might have been driven by a suspected pregnancy. Likewise, Katherine Howard, Henry’s fifth wife, was reported by several ambassadors to be pregnant remarkably shortly after her late July marriage to the king.
In September 1540, the Venetian ambassador Francesco Contarini noted that “the new Queen Katherine is said for certain to be pregnant.” Three months later, Charles de Marillac of France described Katherine as “grosse,” a term used in French to refer to pregnancy at that time. These reports continued into 1541, with de Marillac stating that the court was preparing for both Katherine’s coronation and the christening of her child. However, no further mention of this pregnancy was made after Lent of 1541, leading to speculation that Katherine may have suffered a miscarriage or that the reports were exaggerated.
Katherine Parr, Henry’s sixth wife, also faced an uphill battle regarding childbirth. When she married Henry in July 1543, she was 31 years old — and on her third husband. There is no record that there was ever a rumor she was carrying the King’s heir. Yet, five years later, at 36, she did become pregnant, much to the concern of her friends who feared for her safety and much to the joy of her fourth husband, Thomas Seymour. Although Katherine Parr never bore Henry a child, the marriage was consummated, and Henry even made provisions in his will in case she was pregnant when he died.

This string of reproductive failures raises questions about whether the problem lay solely with Henry’s wives, or if the king himself might have contributed to the issues through genetic or health-related factors. As we explore further, we’ll consider the possibility that Henry’s own medical conditions, some of which may have been passed down through his interconnected family tree, played a significant role in the tragic outcomes of his marriages.
After all, Bessie Blount and Mary Boleyn both went on to make marriages after their affairs with Henry and the bearing of his children — marriages that were much more fruitful than any of Henry’s would ever be. They were very much the ones who got away and thrived while doing so.
It All Could Have Ended With Henry of Cornwall

The reign of Henry VIII is often defined by his relentless quest for a male heir, a quest that led to seismic shifts in England’s religious and political landscape. But what if that desperate search hadn’t been necessary? What if Henry, Duke of Cornwall, the princely son of Henry VIII and Catherine of Aragon, had lived? The ripple effects of his longer life would have reshaped the very fabric of English history, possibly preventing the cascade of events that followed his tragic death.
On New Year’s Day in 1511, England’s prayers for an heir were answered with the birth of Prince Henry. Hall’s Chronicle paints a bright picture of the realm’s rejoicing as the queen took to her birthing chamber, and the king celebrated Christmas at Richmond Palace. As the new year dawned, the nation rejoiced at the arrival of a male heir, a moment that was met with grand celebrations, fountains filled with wine free for the peasants’ enjoyment, and preparations for the boy’s christening. The ceremony was as illustrious as the moment demanded and took nearly a week to plan.

Yet, the joy was tragically short-lived. After only 52 days, on February 22, the young Prince Henry passed away at Richmond Palace, apart from his parents’ royal presence. His death was sudden and shocking, with no prior record of illness. Hall’s Chronicle describes the event with solemnity saying that the boy’s death caused his mother deep lamenting and his father to have to comfort her in front of the court.
The implications of Prince Henry’s survival are tantalizing to consider. Had he lived, Henry VIII’s obsession with securing a male heir might never have had to take root, thereby altering the course of history. The infamous break with Rome, which was largely fueled by Henry’s desperation to annul his marriage to Catherine in pursuit of a younger, more fertile Anne Boleyn, might never have occurred. Without the need to seek a divorce, Henry might have remained a steadfast ally of the Pope, preserving England’s Catholic identity for a longer period.
In this alternate reality, the English Reformation could have taken a very different path — or perhaps not occurred at all. The Dissolution of the Monasteries, the rise of Anglicanism, and the violence of the religious conflicts that followed might have been avoided or at least delayed. England’s political, religious, and dynastic landscape would be unrecognizable from the history we know today. Think of it: Henry and Catherine could have remained married; Anne Boleyn would have been allowed to marry her Irish cousin; there would have been no King Edward or Queen Elizabeth; Mary would have been born later and allowed to make a dynastic marriage at a younger age; and Henry could’ve lived to see a grandson born who could carry the Tudor line into the far future.

The cause of Prince Henry’s death remains one of history’s mysteries. He appeared to be a healthy infant at birth, as evidenced by his delayed Christening — sickly infants were usually baptized immediately to allow access to heaven. His was well documented and conducted five days after his birth, suggesting no immediate concern for his well-being. Yet, without enough warning to call his parents to his side, he was gone. Theories have been floated, from crib death to a respiratory infection—after all, the Tudors were constantly claiming their lungs were affected by bad air—but the true cause of the little prince’s death is likely lost to time.
In the end, the death of Henry, Duke of Cornwall, was not just a personal tragedy for his parents but a fulcrum that would set the stage for the dramatic events of the Tudor Dynasty. It was a moment where history hung in the balance, and with the loss of a single infant, the future of England was put on a collision course with Rome.
Maybe It Wasn’t the King but His Ancestors

While Henry VIII is often the focal point of discussions about the Tudor Dynasty’s reproductive struggles, it is worth considering that the problems might have originated with his ancestors. The Tudor line was relatively new, established by Henry VII after his victory at the Battle of Bosworth in 1485, making him a king by force rather than by right.
The Tudors, like many royal families, practiced endogamy, marrying within a limited gene pool to preserve their claim to the throne (the older King Henry VII’s was tenuous at best). This practice could have introduced or perpetuated genetic conditions that affected Henry VIII and his offspring. Exploring the medical history of Henry’s parents and grandparents might provide clues about the inherited health issues that eventually ended the line of Tudor sovereignty.
Blood Conditions

One crucial but often overlooked factor that played a role in Henry’s repeated failures to secure a healthy male heir may very well have been rooted in something as microscopic as his very blood cells. Specifically, the Kell blood group and Rh incompatibility may have been the silent saboteurs at the Tudor court.
The Kell blood group is a genetic marker that can cause significant complications in pregnancy when the mother and fetus have incompatible blood types. In Henry VIII’s case, the issue wasn’t just about bad luck; it may have been about bad blood — literally. Henry was likely Kell positive, something experienced by less than 10% of the British population, and his Kell-positive blood was passed on to his children in utero. The immune systems of his wives, all of whom were likely the far more common Kell negative, may have responded with deadly consequences.

The first pregnancy for a Kell-negative mother might proceed without issue because her immune system has not yet encountered Kell-positive blood. However, during childbirth, if the mother’s blood is exposed to the baby’s Kell-positive blood, her immune system becomes “primed.” Like an immune system encountering the common cold for the first time, the body learns that something is harmful and fights it off, though with the Kell blood group the fighting happens in subsequent pregnancies, making it so her body would see any Kell-positive blood as a threat and start producing antibodies to destroy it. These antibodies would then attack the blood cells of any future Kell-positive fetuses, leading to hemolytic disease in the newborn.
In the 16th century, such a condition would have been undetectable and therefore fatal for the either unborn or newborn child, with no hope for intervention. We do know that some of Henry’s babies made it through the turbulence of a Tudor birth but succumbed to unknown circumstances quickly after.
Today, thanks to advancements in medicine, babies affected by hemolytic disease can often be saved through blood transfusions, sometimes even while still in the womb. But in the time of Henry VIII, such medical interventions were unheard of and the science behind such procedures was generations away.

Consider Catherine of Aragon, Henry’s first wife, who endured an agonizing series of pregnancies. She produced five babies who died within days or weeks of delivery, three of whom were sons. Only Mary, born in 1518, seven years after elder brother Henry of Cornwall whom she’d never meet, survived. If Catherine was Rh-negative and either of her husbands—first Arthur, Henry’s elder brother, and then later Henry himself—was Rh-positive, her body might have developed antibodies due to exposure that compromised her eventual pregnancies. This would explain why her obstetric journey, especially those resulting in male children, ended in neonatal death. The destruction of the baby’s red blood cells due to these antibodies could have been a primary factor in these losses.
Adding another layer to this genetic puzzle is the fact that Henry VIII was related to all of his wives in some way, thanks to the intricate web of the European aristocracy. This cousinhood could have exacerbated any underlying genetic conditions, making the likelihood of complications even higher. In a time when royal bloodlines were more a matter of prestige than genetics, the interconnectedness of the European nobility may have been more a curse than a blessing.

Henry’s second wife, Anne Boleyn, faced similar struggles. After the birth of Elizabeth, Anne suffered multiple miscarriages, which some historians speculate could have been due to the same Kell-related issues that plagued Catherine. Jane Seymour, Henry’s third wife, managed to produce a male heir—Edward VI—but she too may have suffered from miscarriages before successfully carrying Edward to term. Was Edward one of the lucky babies to be Rh negative, like his mother?
The cruel irony of Henry’s reign is that his obsessive quest for a male heir may have been thwarted not by fate, but by the very blood coursing through his veins. No matter the cause, it is clear that the story of Henry VIII’s heirs is as much a tale of biology as it is of politics and inheritance.
Diabetes and Chronic Malaria

Imagine a young, vibrant Henry — strong, handsome, and full of life. This was a man who had survived smallpox, numerous sore throats, and even the dreaded “ague,” known today as malaria. In those days, malaria was a common affliction, especially in marshy regions and places where mosquitoes surrounded the River Thames. The disease was so prevalent that it was almost an expected part of life for those living near the river, with outbreaks continuing well into the Victorian Era.
If Henry suffered from chronic malaria, it might have been the starting point of his fertility issues. Malaria was a frequent and deadly companion in the damp Thames marshes, and its effects could linger long after the initial infection, causing recurring fevers, chills, and a general decline in sperm quality.
As if the ravages of malaria weren’t enough, Henry could’ve been diabetic, a condition that, in the 16th century, was a death sentence in slow motion. The king’s legs, once strong and capable, became sites of unbearable pain and decay. He suffered from varicose veins that ulcerated, leaving open sores that refused to close properly. This was a common complication for diabetics, where even a small cut, particularly on the lower legs or feet, could lead to a gangrenous ulcer — a wound that would only deepen with time.
And worsen it did. The smell of Henry’s rotting legs reportedly preceded him by several rooms, a pungent reminder of the once-great monarch’s mortality. In modern times, these ulcers would be treated with advanced medical care, possibly even leading to amputation to prevent the spread of infection. But for Henry, there was no such relief. If he did have uncontrolled diabetes, it may have ravaged his body while simultaneously contributing to his difficulties in producing a hale and hearty male heir.

Recent research indicates a strong link between diabetes and male infertility. A study found that a majority of men with diabetes experienced subfertility and, in the worst-case scenarios, complete infertility. If Henry’s blood sugar levels were as uncontrolled as his temper, it is no wonder that he struggled to father children who could survive infancy.
The image of Henry VIII that persists in popular culture often focuses on his larger-than-life personality, his tyrannical rule, and his six ill-fated marriages. But beneath the crown and the royal accouterments was a man slowly being eaten away by disease — his own body betraying him in ways that no political enemy could. It is a question of either or both when considering diabetes and chronic malaria that could have afflicted Henry. On their own, each of these conditions could’ve played a significant role in the tragic infant losses that haunted his lineage.
Lupus Erythematosus and Klinefelter’s

In the gallery of Henry VIII’s potential ailments, two rare but significant conditions may have further complicated his health and his relentless quest for a male heir: systemic lupus erythematosus (SLE) and/or Klinefelter syndrome. Both disorders, though vastly different in their manifestations, could have played a role in the mysterious decline of Henry’s health and the tragic pattern of infant mortality that plagued his marriages.
Systemic lupus erythematosus is a chronic autoimmune disease that can affect nearly any organ system, from the skin to the heart, kidneys, and lungs. It is a disease most commonly associated with young women, striking them at ten times the rate of men. But that doesn’t rule out the possibility that Henry VIII, with his broad spectrum of health issues, could have been the rare male sufferer. SLE is notorious for its unpredictable attacks and the production of antibodies that attack the body’s own tissues, leading to a host of debilitating symptoms.
Henry could have been an earlier version of another royal who struggled to produce heirs for England. Consider the horrific tale of Queen Anne, who endured a staggering 17 pregnancies, only to see each end in miscarriage, stillbirth, or the early death of her children. Modern historians believe she was plagued by SLE and its cruel companion, antiphospholipid antibody syndrome, a condition that causes blood clots, strokes, and repeated pregnancy losses. Could Henry VIII have faced a similar, albeit less understood, struggle? Like Henry, Anne had a single child survive, a longed-for son, who made it only to his eleventh birthday.

Henry’s bouts of illness, his chronic leg ulcers, and his apparent fertility issues might point toward an autoimmune disorder like lupus, though the exact cause remains speculative. If he had SLE, it is possible that his immune system was not only attacking his body but also complicating his wives’ pregnancies.
On the other hand, Klinefelter syndrome presents an entirely different challenge. This chromosomal disorder affects males, giving them an extra X chromosome, resulting in a typical karyotype of 47, XXY. Men with Klinefelter syndrome often face a range of physical and cognitive challenges, including tall stature, small testes, and infertility — traits that might have been easily overlooked or misattributed in Henry’s time.
While it is unlikely that Henry VIII exhibited the classic signs of Klinefelter syndrome, such as gynecomastia (enlarged breasts) or a lack of masculine traits, it is possible that a milder, less obvious form of the condition contributed to his difficulties in producing a viable male heir. The syndrome is also associated with neurocognitive and behavioral issues, which could offer some insight into the King’s increasingly erratic behavior as he aged. The progressive testicular failure associated with Klinefelter syndrome could have led to a gradual decline in fertility, exacerbating the pressures on Henry to secure a male successor.
Each failed pregnancy, and each lost child would have been a blow not just to the Tudor Dynasty but to Henry’s own sense of identity and value to his people as a monarch.
The possibility that Henry VIII could have been afflicted by either of these conditions underscores the complexity of his medical history — a history that was as tumultuous and tragic as his years on the throne.
Does Henry’s Line Live on Through His Unrecognized Daughter?

In the vibrant and politically charged court of Henry VIII, the king’s early mistresses, Bessie Blount and Mary Boleyn, stand out not just for their beauty but for their timing. Both women had Henry when he was young, virile, and seemingly less rocked by the maladies that would later ravage his body and mind. Bessie Blount bore him a son, Henry Fitzroy, who was openly acknowledged and given the best titles the king could offer an illegitimate child. Mary Boleyn, on the other hand, carried his legacy in a more covert manner.
As Henry’s health began to deteriorate—his body increasingly plagued by ulcers, possible diabetes, and perhaps a host of other conditions that impacted his fertility—his official unions became less fruitful. Yet, it is these early extramarital affairs, before the shadow of illness darkened the halls of Hampton Court Palace and Whitehall, that may have truly secured his line.
While Bessie Blount’s son lived a privileged life in a bright spotlight, it was Mary, the king’s quieter, more enigmatic lover, who might have ensured that the Tudor bloodline carried on in the most unexpected of ways. Catherine Carey, Mary’s daughter, is widely believed to have been Henry’s child. Unlike her half-brother, Fitzroy, Catherine was not acknowledged as Henry’s offspring, but the historical evidence and the timing of her birth suggest that she was indeed the king’s daughter.
Catherine Carey’s line leads directly to notable figures in modern history, including both Charles III and Diana, Princess of Wales. Charles traces his lineage back to Catherine’s daughter, Lettice, while Diana’s connection is through Henry Carey, Catherine’s younger brother. And in a twist that would surely have infuriated the notorious king, one of Catherine Carey’s descendants is none other than Kate Middleton, the current Princess of Wales.

Isn’t it ironic? Those who sit on the throne today are not as much Tudors as they are Boleyns. Kate Middleton, Catherine Carey’s several times granddaughter, is married to the current heir to the British throne and mother to another. Philippa Gregory, author of The Other Boleyn Girl, notes, “Catherine was born at the height of Henry’s passion for her mother.” And so, as Henry VIII continued to forge ahead with his ill-fated marriages, desperately seeking an heir, it may have been Mary Boleyn who truly carried his line forward. Through Catherine Carey, Henry’s blood—though unrecognized—survived and flourished in a lineage that now sits atop the British monarchy.