When Dr. Mushtaq Ahmed operated on ten-month-old baby Shazia to remove what was suspected to be a cyst, he was stunned to see a pair of half-formed feet inside her stomach.
"My team expected to find a cyst or abdominal mass in this baby who had been crying in pain for months, but when we opened the baby's abdomen and saw the toes and spine, I was momentarily speechless.
"I have not come across a case like this in the 15 years I have been working as a pediatric surgeon," says Dr. Ahmed.
Describing this amazing discovery, Dr. Mushtaq says his team realized they were looking at the fetus of an unborn twin baby Shazia.
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He was probably eight to nine weeks old when he stopped developing.
"We could clearly see the beginnings of all four limbs with clearly visible toes, and we could even notice shapes resembling eyes," he says.
The operation to remove the fetus was performed in Pakistan, at the Sheikh Zayed University Hospital in Rahim Yar Khan, in the southern Punjab region.

'Fetus in fetu'
In the medical world, this rare condition where an unformed parasitic fetus resides in the body of its twin is called "fetus in fetu".
It is not known what causes it, but this condition occurs in the early stages of development, when one fetus wraps around another.
The enveloped fetus does not fully develop, but becomes a "parasite," relying on the host twin to survive.
Such twins usually die before birth.
It is estimated that this anomaly occurs once in every 500.000 births, according to the report 2000 American Academy of Pediatrics.
So far, only 200 cases of this anomaly have been reported in the world.

Excessive crying
Baby Shazia's stomach began to swell a month after birth.
Her parents say that she was crying because of the pain and that it lasted for a long time.
"We didn't know what the problem was, but her stomach was hard to the touch," says Muhammad Asif, Shazia's father.
Farmer Asif and his wife, along with two other children, took Shazia to several doctors in their hometown of Sadiqabad.
But due to the lack of medical facilities and the condition being so rare, Shazia was not diagnosed.
When the baby's condition worsened, they decided to travel 25 kilometers to the better-equipped Sheikh Zayed Hospital in Rahim Yar Khan on August 30.
A few hours later, they met Dr. Mushtaq.
"When I examined the baby, I felt some kind of tumor.
"I did an ultrasound and diagnosed some kind of cyst in the abdomen.
"I didn't even consider the possibility that it could be something else," he says.

Parents could not afford magnetic resonance imaging, which would have enabled a more accurate diagnosis.
Doctor Mushtak advised that surgical removal of the cyst is the best option.
"That scared them, they didn't understand why such a small baby needed an operation and they got worried," says the doctor.
Shazia's parents refused the operation and went home.
But a few days later they returned, desperate to do anything to make their child's life easier.
"The family is very poor and barely making ends meet, so our clinic gave them a big discount so they could pay for the surgery," explained Dr. Mushtak.
But when a team of doctors made the startling discovery about Shazia's unborn twin during surgery on August 29, they realized they had to perform a delicate procedure to remove the fetus.
"We were amazed when we discovered that this malnourished baby was carrying the fetus of its own twin," the doctor points out.
The fetus acted like a parasite, attaching itself to the baby's small intestine, drawing blood and depriving Shazia of vital nutrients.

Doctor Mushtaq says that Shazia recovered almost immediately after the operation and is now growing normally.
"She stopped crying and we noticed that her condition has improved since the operation," he says.
Shazia was released from the hospital on September 4, four days after the procedure.
The pediatric care team will monitor her condition in the coming months and report the details of this case in a scientific journal.

Rumors about the "pregnancy" of the baby
Due to the rarity of the case, there was huge media interest in Shazia's story.
Her father turned off his cell phone to avoid answering disturbing questions.
"Newspapers and TV stations called to ask how we were dealing with the baby's pregnancy and asked us all sorts of uncomfortable questions," he says.
The hospital team says it has provided clarification to local journalists and counseling to Shazia's parents, who are upset over questions about false "pregnancy" reports.
Dr. Nadim Aktar, head of the pediatric surgery department at the Pakistan Institute of Medical Sciences (PIMS) in the capital Islamabad, emphasizes that "fetus in fetu" has nothing to do with pregnancy.
"Many journalists wrongly report on this topic and, due to ignorance, associate this case with pregnancy, which upsets the patient's family
"This fetus-like mass doesn't necessarily always have the ability to grow or spread in the body, as a pregnancy or a tumor would.
"It usually stays where it was formed, mostly in the lower abdomen," says Professor Aktar.
Other cases of "fetus in fetu"
A widely reported case was that of a thirty-six-year-old man from India whose alleged tumor had grown so large that he had difficulty breathing.
Doctors operated on him after he complained of severe stomach pains.
They expected to find a large tumor, but instead found a huge mass consisting of the half-formed body of his unborn twin brother.
The fetus managed to survive for so long because it behaved like a parasite, forming an umbilical cord-like structure to draw blood from the human bloodstream.
Doctors say that it is possible for someone not to know that they have a fetus inside them if they live in villages or smaller towns, where access to health facilities is limited.
This city in India is full of twins - and no one knows why:
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