Parasitic twins: I have accepted my baby born with two heads and three arms

parasitic twins,birth defects, twins, Heterophagus twins

It is thought that the occurrence of parasitic twins, also known as heteropagus twins, is 1 in 500,000 to 1 in 1,000,000 births. 

Photo credit: SHUTTERSTOCK

What you need to know:

  • Heterophagus twins are a special type of conjoined twins in which tissues of an incompletely formed twin are attached to and depend on the normal twin to survive.
  • It is thought that in the early part of pregnancy, as identical twins form, any injury to the developing placenta may compromise one of the twins, interfering with their development.
  • The surviving tissue may latch on to the normal twin to access oxygen and nutrition to ensure survival. 

Speranza* could not wait for the rain to stop. At 5 am, she had woken up, taken a shower, packed her bag, and headed to the hospital. She was 35 weeks pregnant and in labour. She knew she needed someone to check on her baby. She hadn’t felt her baby move all night, and it wasn’t quite time for baby to come. 

Speranza’s taxi pulled into the hospital entrance just as dawn broke over the city horizon. The sleepy security officer helped her to the labour ward, seeing that she was alone. The exhausted midwife mechanically took her through the preliminaries, listing her complaints and performing a quick examination. Her demeanour changed when she realised that, try as she may, she could not hear the baby’s heartbeat. 

She admitted Speranza to the ward and immediately alerted the doctor who was busy with morning reviews. The doctor was dog-tired. It had been a chaotic night in the busy maternity unit. This wasn’t how she wanted her shift to end but she too had confirmed that Speranza’s baby was no more. Further, Speranza’s baby was coming bottom first, in breech. 

By the time I took over the shift at 8 am, Speranza had cried her heart out at the news. The midwife attending to her briefed me before we got to her bedside. Despite the grief, Speranza still had to valiantly bear with the labour until she delivered her little angel. I prescribed a repeat injection to ease some of her pain as she neared delivery. 

I went on to review the other patients in the unit but an hour later, I was urgently summoned back to Esperanza’s bed. Her baby had been delivered partially. The legs and most of the body had come out but the head and arms were still stuck inside her. A lot more hands showed up to help and with the help of some unusual manoeuvres, the baby slid out, followed by the placenta. 

There was a collective gasp from the midwives while I tried to keep a poker face. Speranza nearly sat up, wanting to see what had shocked the midwives. 

I gently pushed her back on the bed, carefully wrapped her baby as best as I could and cut the umbilical cord. The recovering midwives took over the remaining tasks while I tried to find the words to explain to Speranza that her baby wasn’t going to be easy to see.

Speranza wasn’t one to be subdued. She insisted on seeing her baby. Save for the lifeless grey skin tone, the little one looked completely normal from his navel downwards. Above the abdomen, not so much! 

Speranza’s baby had three arms, two on each side and one sticking out his upper back. He also had mass just below the neck that closely resembled a second head, mostly covered with hair. The actual head was slightly flattened and misshapen. It appeared that Speranza had lost not one, but two babies. This wasn’t a sight for any mother who had just given birth to a still born baby. 

Speranza had given birth to a baby who had a parasitic twin attached, an exceptionally rare condition all world over. It is thought that the occurrence of parasitic twins, also known as heteropagus twins, is 1 in 500,000 to 1 in 1,000,000 births. The numbers are so few that the existing literature on the condition is based on case reports. 

In 2018, the Elsevier Journal of Paediatric Surgery published a case series from our neighbouring country, Ethiopia, detailing five children born with this condition, treated in a teaching and referral hospital over a nine-year period. All of them successfully underwent surgery and made it out alive. 

Heterophagus twins are a special type of conjoined twins in which tissues of an incompletely formed twin are attached to and depend on the normal twin to survive. It is thought that in the early part of pregnancy, as identical twins form, any injury to the developing placenta may compromise one of the twins, interfering with their development. The surviving tissue may latch on to the normal twin to access oxygen and nutrition to ensure survival. 

As a result of the unpredictability of what type of parasitic tissue survives and where the attachment occurs, the parasitic twin may be attached to any level of the spine, along the back, from the neck to the sacrum; the hip, the abdomen or the chest. The attachment may just be soft tissue or may involve bones. 

The ultimate treatment is to separate the parasitic twin from the normal baby by surgery. The complexity of the surgery depends on the location of the parasitic tissue, the organs involved, the size and any other underlying medical complications the baby may have. For instance, where the spinal cord is involved, surgical injury can easily result in paralysis of the limbs, with lifelong confinement to a wheelchair. 

For the Ethiopian study, one child, a 12-year-old, had an extra leg growing out of his right side, at the level of the pelvis. The second one was a baby with a leg, complete with the buttocks, growing out of his abdomen, attached to his liver and lower end of sternum. The third baby had a complete leg and buttock growing out of the lower back. The fourth baby had a shapeless mass on the lower back with male genitalia sticking out of it. The last one had a complete pelvis, with buttocks and both legs, growing out of the lower back, facing away. 

All these babies had a successful surgery to remove the parasitic tissue, restore normal function and improve the general aesthetics of these little ones. Surgery also ensures that the baby’s heart and lungs are not overwhelmed by the additional duty of providing oxygen to these parasitic tissues, a state that can compromise their function. Recovery is a long road, with physiotherapy to improve function and family support through such a difficult diagnosis.

Speranza wasn’t so lucky. Her babies did not live to benefit from possible surgery. I pray that the experience did not frighten her out of motherhood.

Dr Bosire is an obstetrician/gynaecologist