What You Need To Know About Fetus In Fetus (parasitic Twins)

The first case of fetus in fetus was reported in 1800. Since then, about 200 cases have been reported worldwide. The rarity of this anomaly and its geographical dispersion prevented in-depth studies of this phenomenon.

Meckel first discovered this strange anomaly. He gave it the name fetus in fetus to refer to those cases in which a parasitic twin is found inside his healthy brother, who serves as his host.

It is very common for doctors to initially diagnose this problem as a painless lump. 89% of cases were detected in the first 18 months of life. However, there are also many cases of delayed diagnosis.

Fetus to fetus is a rare problem

This abnormality is one of those rare diseases. To date, 7,000 diseases have been included in this category. Fetus in fetus is among the 10 rarest diseases discovered so far.

There are only about 200 documented cases worldwide. This abnormality occurs in about 1 in 500,000 births. In most cases, doctors diagnose it during childhood. However, the problem was also discovered in adults up to 47 years old.

It is a variant of the parasitic twins

The anomaly is a variant of the phenomenon known as parasitic twins. This is a condition in which there are twins attached and one of them has a much smaller body than the other.

In these cases, the host twin allows the parasite to survive because the latter does not have its own organs. It has also been considered an extreme case of Siamese twins.

Fetus in fetus is an accident

Scientists do not know exactly the cause of this phenomenon. I only know that it is an accident that happens at some point during the formation of the zygote. For some reason, the twins do not separate completely and remain attached.

All this happens before the embryo is formed. After that, one of the twins develops normally, while the other atrophies. For this reason, it remains inside the healthy twin and depends entirely on it for survival.

The humanoid looks weird

It is common for the host fetus to die before birth. The baby has a swelling in the area where the parasitic twin is housed. In 80% of cases, this happens in the abdominal region. However, it is possible for parasitic twins to make their way into the scrotum, skull, etc.

Fetus in fetus is a humanoid. When doctors remove it, it is wrapped in a membrane that makes it look similar to a chicken egg. However, it is extremely heavy and quite large. When removed from the membrane, the parasitic twin is white. When doctors perform this procedure, the parasitic twin dies because it depends entirely on the healthy brother.

Fetus in fetus and teratoma

A teratoma is an encapsulated tumor that contains remnants of tissues and even organs. There are known cases of teratomas that contain hairs, teeth, bones and even hearts, although this is quite rare.

Due to its characteristics, the teratoma is sometimes confused with the fetus in the fetus. The researchers established criteria to differentiate the anomalies. Teratomas can become malignant, but not the fetus. Likewise, to name it fetus in fetus, the humanoid must have a spine.

It poses a risk to the host

Parasitic twins pose a risk to healthy twins. It turns into a load that you carry inside your body for no purpose and can weigh up to 1 kilogram (2.2 lbs). They do not have a brain, but an empty cranial cavity and also do not have a thoracic cavity, but only muscle tissue.

The risk also depends on the location of the parasitic twin. As already mentioned, it is almost always located in the abdomen. However, there are cases in the oral cavity (6), skull (7-9), liver (10) and other dangerous locations. 13 cases have been reported in which more than two parasitic twins coexist.