The baby boy was born with extra limbs in Sukkur. He was Monday shifted to the National Institute of Child Health (NICH) in Karachi.
NICH director Jamal Raza said the infant has a parasitic twin.
"One of the twins is living, while the other has become parasitic. The infant is all right and has been admitted to the intensive care unit of the NICH, but the removal of the parasitic limbs could be a serious and time-consuming medical exercise including both inner and cosmetic surgeries," Dawn quoted Raza as saying.
A team of five surgeons will look into this case.
The baby's father, Imran Ali Sheikh, 31, is an X-ray technician who married Afshan, 27, about five years back.
The baby is their first child.
"I want the doctors to save my son's life," he pleaded.
"I am a poor man and have already spent my savings on the illness of my wife who delivered the child after a caesarean section April 12 at the Civil Hospital Sukkur," he added.
Photos: Vaani Kapoor, Poonam Pandey, Sana Khan at fashion event
Photos: Rishi Kapoor, wife Neetu, daughter Riddhima at book launch
How Angelic! 10 stunning pics of birthday girl Angelique Kerber
Photos: Sunny Leone, Shraddha Kapoor, Shriya Saran at Mumbai airport
Spotted: Shah Rukh Khan at Mehboob Studio