In early February 2004, the press reported the birth of a ‘Two-Headed Baby’ in the Dominican Republic. Eight weeks earlier, on 10 December 2003, Rebeca Martinez (below, with her family) had been born with a second head joined to her own, crown to crown, but without any other obvious developmental defect. The second head had partially developed eyes, ears and lips and grew quicker than the lower one, probably due to hydrocephalus caused by defective venous drainage. Leading American surgeons with considerable experience of separating conjoined twins were consulted, a charity paying for all expenses, and they planned to operate before the weight of the second head made it impossible for Rebeca to lift her own. The operation started out well, and the surgeons even issued an optimistic press statement halfway through their work. But, tragically, the unfortunate little girl died from a heart attack caused by the massive blood loss during the 11-hour operation on 7 February 2004. (See FT179: 6-7 for other recent examples of conjoined twins).
The sad story of the ‘Two-Headed Baby’ was a five-day wonder all over the world. From Maine to Mexico and from Stockholm to Sydney, newspapers gave their views on this singular event. Some papers tried their best to present a factual account, although struggling hard to understand the medical facts, while others painted a gory and sensational picture of the brave little girl and the horrific operation she was to undergo. Without exception, the press coverage was ill-informed, indicative of the failure of modern ‘medical journalism’ in which the reporters appear to understand very little of what they are writing about. In this unfortunate situation, they have a tendency to rely on dubious authorities, like a local ‘expert’ on conjoined twins who held a press conference after what must have been a very brief session reading up on his subject.
Following this dubious authority, the world’s press unanimously regurgitated the false information that although there had been some previous instances of this malformation, none of them had been live-born.
The majority of newspapers followed the age-old tradition and presented the Two-Headed Baby as a mysterious ‘freak of nature,’ without making any attempt to satisfy the curiosity of their readers about what could have caused a newborn infant to have a second head fused with its own. The explanation is relatively simple. Conjoined twins are divided into groups from the area of conjunction, one of the groups being craniopagus twins, i.e. joined at the skull. In rare instances, the body of one craniopagus twin atrophies in utero due to deficient placental blood supply, and the result is craniopagus parasiticus conjoined twins, where the ‘normal’ twin has a parasitic head and rudimentary body attached to the crown of the head. There are nine previously described cases of craniopagus parasiticus, two of whom have been live-born. The only one capable of prolonged extra-uterine life was the famous Two-Headed Boy of Bengal, born in 1783. Just like the recent Dominican Republic case, this boy had a parasitic head on top of his skull. This parasitic head was reasonably well developed and showed clear signs of independent life.
In 1790, the Two-Headed Boy of Bengal was described by the surgeon Everard Home. Home was the brother-in-law and principal assistant of the celebrated John Hunter, and a medical scientist of some repute. He rightly claimed that the Two-Headed Boy was “a species of lusus naturæ so unaccountable, that, I believe, no similar instance is to be found upon record.” Home never went to India to see the boy, but collected several descriptions and drawings of him from laymen. The Two-Headed Boy was born in May 1783 in the village of Mundul Gait in Bengal; his parents were poor farming people. Immediately after the child had been delivered, the midwife, who was terrified by its strange appearance, tried to destroy the infant by throwing it into the fire; he was saved from the flames with burns on one eye and one ear of the upper head. The parents soon realised the possibility of earning money by exhibiting their child in Calcutta, where he attracted much attention. Large crowds gathered to see the Two-Headed Boy; to hide him from the eyes of people sneaking up to see him, his parents had to cover him up between the shows. In this way the boy spent his short and miserable life; his emaciated and sickly appearance, Home thought, was caused by his being covered with sheets most of the time. The Boy’s fame soon spread all over India, and several noblemen and civil servants had him exhibited in their houses. One of these, Colonel Pierce, described him in a letter to the President of the Royal Society, Sir Joseph Banks, who later gave the letter to Everard Home.
The two heads were of equal size and covered with black hair at their junction; the upper head ended in a neck-like stump, which one observer likened to a small peach. When the boy cried or smiled, the features of the upper head were not always affected, and their movements seem to have been purely reflex: a pinch in the cheek produced a grimace, and when it was given the breast, its lips attempted to suck. The natural head and body were quite normally developed, but a number of anomalies were noted in examining the parasitic head: the corneal reflexes were absent and the eyes’ reaction to light was weak. No pulsations could be felt in the temporal arteries of the parasitic head, but its superficial facial veins were well filled with blood. The ears were malformed, and the tongue small. The lower jaw was rather small, but capable of motion. The secretion of tears and saliva was plentiful. When the child slept, the eyes of the parasitic head could be observed to be open and moving. When he was first awakened, all four eyes moved in the same direction, but normally, the two heads’ eye-movements were independent.
When the boy was four years old and in good general health, his mother left him one day, walking off to the village to fetch water. On her return, her son was dead from the bite of a cobra. Several scientific amateurs made offers to purchase the corpse, but the religious parents did not allow it; instead, they buried their child near the Boopnorain river, outside the city of Tumloch. The grave was later plundered by Mr Dent, the East India Company’s agent for salt in this city. He dissected the putrefied body and kept the skull, which he gave to Captain Buchanan of the same company. The captain brought the skull to England, where he gave it to his friend Everard Home. When Mr Dent had dissected the heads, he had noted that the brains were separate and distinct, each enveloped in its proper coverings. The dura mater of each brain adhered firmly and contained many large vessels, supplying the nutrition to the upper head. In his examination of the double skull, Everard Home noted that the halves were nearly of the same size. No septum of bone existed between the two brains. The natural skull was quite normal, but the parasitic one was imperfect in a number of particulars, and its facial bones were generally smaller. The skull can still be seen at the Hunterian Museum of the Royal College of Surgeons of London.
Everard Home much regretted that medical scientists never got the opportunity to examine the boy. The two brains and their influence on the intellectual principle fascinated him. Neither Home nor John Hunter speculated about how the Two-Headed Boy should be classified in the system of teratology. They do not seem to have noted the similarity between the boy and the symmetrical conjoined twins of the type craniopagus that are joined at the crowns of the heads. The junction may be more or less extensive: in partial craniopagi, the crania are intact or simply fused, while in total craniopagi, the two brains are encased in a common cranium. While, in the former subgroup, the brains are often quite intact, those of the latter subgroup are sometimes malformed. Craniopagi had been described several times in the old annals of teratology. The famous twins of Worms, born in 1495 and depicted in several crude woodcuts of the time, were frontal craniopagi and lived for 10 years. During the 18th century, several well-attested cases were reported. Today, at least 80 bona fide cases of craniopagus conjoined twins have been described; this type represents six per cent of all double monstrosities, making the incidence 0.6 per million births. The surgical techniques for separating craniopagus twins have greatly improved during the last decades, but the operation is still a most uncertain and difficult venture, especially in cases with total conjunction and malformations of the brains and their vascular supply.
In his Traité de Tératologie (1836), the famous French anatomist Isidore Geoffroy Saint-Hilaire was the first to note the similarity between the Two-Headed Boy of Bengal and craniopagus conjoined twins. He suggested that the Two-Headed Boy belonged to a special group of parasitic craniopagi, and quoted a similar French case, described by the Liège surgeon M Vottem in 1828. Here, the parasite had been much larger than in Home’s case, with incompletely developed arms and a rudimentary spinal column. The monstrous fœtus was seen to gasp for breath and move slightly for about half an hour; after its death, the mother was told she had given birth to a stillborn normal child, in order not to disturb her. In all, 10 cases of this teratological type have been reported. The teratogenetic mechanism is that the two fœtuses are originally conceived as symmetrical craniopagus conjoined twins, but that one twin loses its contact with the umbilical vesicle, which explains the underdevelopment of the parts not directly supplied with blood through anastomoses from the healthy twin. This theory is supported by the fact that in several cases, the neck-like stump on top of the parasite’s head has proved to contain a small sternum, clavicles and a number of underdeveloped ribs, as well as a rudimentary heart, pharynx and lungs
This has some interesting implications for the recent Dominican Republic case. It is not correct to state, as the newspapers did, that the parasitic head would ‘kill’ the normal twin, nor it is obvious that the parasite would seriously hinder the development of the natural brain. From the sketchy accounts of the operation, it appears that the ‘extra brain’ was successfully removed, and the cranium in the process of being closed, when the complications occurred. It is also notable that modern imaging techniques were used to investigate the relationship of the two brains, and in particular their blood supply and venous drainage, and there was probably a good reason why the operation was performed when the child was just two months old. This important question was never asked by the media, who appear to have found it obvious that the ‘hideous monster’ should be restored to normalcy with as little delay as possible.
It is also notable that there was no newspaper discussion about the legal status of the parasitic head. Just as in the Bengal case, it showed independent signs of life, although its features were much less distinct than in the earlier case. It was clearly observed that the eyelids of the upper head twitched, and that its lips moved when Rebeca was breast-fed.
According to the newspapers, tests detected activity in the second brain. From the point of view of the medical scientist, it makes sense to amputate the parasitic head, but would this be the view of the philosopher, who might have objections to deliberately killing a being that showed signs of independent life? We will never know in this particular case, since the journalists found it only natural that the ‘monster’ had to be ‘cured’: the second head was to be cut off like a wart. Such ‘sacrifice surgery’ where one viable conjoined twin is deliberately killed to save the life of another, is an ethical minefield, and is becoming more commonplace as surgical techniques improve and extensively conjoined twins are operated on.
The Two-Headed Boy of Bengal received a fitting obituary by two of the leading medical scientists of their time. Garbled accounts of his life are to be found in many of the popular works on monstrosities. The newspaper obituaries of his modern counterpart in the Dominican Republic, the second viable case of this extremely rare birth defect ever recorded, are less praiseworthy. Not only are they poor examples of medical journalism, in that many ‘facts’ were wrong, and that they failed to observe that there was an earlier instance , but they entirely avoided discussing some of the deeper issues that must have crossed the minds of many newspaper readers. What is monstrous and what is normal; is life as a conjoined twin a life worse than death; and what might have gone on in the semi-dormant brain of the parasitic head?