What is Diprosopus?

Article Details
  • Written By: Marjorie McAtee
  • Edited By: W. Everett
  • Last Modified Date: 11 October 2019
  • Copyright Protected:
    Conjecture Corporation
  • Print this Article
Free Widgets for your Site/Blog
As President of Uruguay, José Mujica refused to live in the presidential mansion and gave away 90% of his salary.  more...

October 16 ,  1964 :  China became the fifth country in the world to successfully detonate a nuclear bomb.  more...

Diprosopus, also known as craniofacial duplication, is a rare congenital disorder. Babies both with this condition are generally considered a type of conjoined twin. These babies often have two sets of facial features. Some may have only a few duplicate facial features. For instance, two noses or two pairs of eyes may appear on the face, while other facial features appear as normal. In the most extreme cases of diprosopus, two complete faces can be found on a single head. The rest of the body generally appears normal.

Conjoined twins are rare, occurring in only about 10% of twins born alive. Conjoining of twins is believed to occur between the 13th and 25th days of pregnancy. Conjoining of twins probably occurs when two sperm fertilize the same egg, and the embryo fails to properly split into two separate fetuses. Diprosopus is considered the most rare form of conjoined twin, with only about 35 recorded cases occurring in the whole world since the condition was first documented in 1884.


Most fetuses stricken with this severe developmental abnormality are stillborn. Many babies born alive with diprosopus don't live long after birth. In 2008, a baby girl named Lali Singh was born in the Indian village of Saini. Lali was born with complete craniofacial duplication, meaning that she possessed two complete faces on a single head. Though Lali was believed to be in otherwise good health at the time of her birth, doctors believe her condition caused serious complications that ultimately led to her death at six weeks of age.

When this condition is discovered during pre-natal ultrasounds, abortion is usually recommended. These fetuses often suffer serious abnormalities in addition to craniofacial duplication. Spinal and brain abnormalities have been spotted on fetuses with diprosopus. These babies often possess two brains as well as two faces, but these brains are usually improperly formed. Some fetuses with diprosopus have been found to be lacking in proper cerebral development, and suffering from hydroencephaly.

These babies generally have a poor chance of surviving in utero until birth, and those that do usually don't survive long after. Babies with craniofacial duplication have been known to survive after birth, if only one brain is present. These fetuses usually develop abnormally large heads, which can make natural vaginal birth dangerous for the mother.


You might also Like


Discuss this Article

Post 4

@Nefertini - This abnormality is caused by an excess of a protein called sonic hedgehog homolog or SHH. The excess SHH production causes widening and duplication of facial features.

Post 3

Do scientists know what causes this congenital disorder?

Post 2

@SimpleByte - you're correct. Diprosopus can also affect cats. Felines with this birth defect are called Janus cats, a name derived from the two-headed Roman deity, Janus. Like humans with diprosopus, cats with the condition usually don't live long. However, a cat named Frank and Louie with the defect lived twelve years and made it into the Guinness Book of World Records.

Post 1

Lali Singh was a tragic case, and the little girl suffered from other birth defects including a cleft palate and opaque corneas. Doesn't this condition sometimes affect cats also?

Post your comments

Post Anonymously


forgot password?