On January 3, 1950, in Soviet Moscow, twin sisters Masha and Dasha Krivoshlyapova entered the world under extraordinary circumstances. As conjoined twins, their birth was already an anomaly—globally, such cases occur once in every 50,000 to 200,000 births. But their story would take a nightmarish turn almost immediately.
Instead of being placed in their mother’s arms, the newborns were seized by Soviet scientists, who saw them not as children, but as living test subjects. Their mother was told they had died.
As she grieved, her daughters were locked away in a Moscow hospital, where they would endure six years of relentless, dehumanizing experimentation.
Human Guinea Pigs in the Name of Science
The Soviet regime considered Masha and Dasha a biological goldmine. They shared the same blood system but had separate nervous systems, making them ideal for testing how the human body responds to extreme conditions. Scientists wanted to explore the limits of pain, endurance, and survival—and the sisters paid the price.
According to journalist Juliet Butler, who later befriended the sisters and wrote about them in “The Less You Know the Sounder You Sleep”, their childhood was a laboratory of horrors.
They were injected with radioactive iodine, not for treatment or any therapeutic purpose, but simply to observe how one twin’s exposure would affect the other. The experiments extended to electroshock procedures, where they were deliberately electrocuted to study nerve responses.
As if that weren’t enough, they endured extreme physical trials, including being burned and frozen to test human endurance in extreme temperatures. The cruelty did not stop there. The twins were starved and deprived of sleep, their bodies and minds systematically broken while doctors took meticulous notes on their suffering. “They were seen as the perfect human guinea pigs,” Butler later revealed.
A Stolen Childhood, a Stolen Life
After six years of torment, the experiments ended in 1956, three years after Stalin’s death. The twins, now old enough to walk and talk, were moved to a boarding school, hidden away from the public eye. It would take decades before they were allowed even a glimpse of the outside world.
In the 1980s, a brief reunion with their mother was arranged, but Masha—dominant and controlling—chose to sever ties. Dasha, described as kind and gentle, followed her sister’s lead. Their bond was unbreakable, but their relationship was fraught with imbalance.
Juliet Butler, who met them in 1988, described them as opposites:
- Masha: Charismatic but egotistical, a heavy drinker.
- Dasha: Quiet, kind, and forever trapped in her sister’s shadow.
Their later years were filled with struggle. Despite their fame as the oldest living conjoined twins, they lived in poor conditions and had to publicly plead for better treatment on Soviet television.
A Tragic End—One Twin’s Death, the Other’s Slow Poisoning
In 2003, Masha suffered a fatal heart attack. But for Dasha, the nightmare wasn’t over. Unable to be separated, she was forced to endure 17 agonizing hours, as toxins from Masha’s decomposing body poisoned her system. With no way out, she too succumbed.
Thus ended the lives of two sisters who had never been given a choice—from the moment they were born to the moment they died.
The story of Masha and Dasha Krivoshlyapova is one of cruelty disguised as science. While their case contributed to medical knowledge, it came at the cost of decades of suffering.
