Sirisha, a science teacher, was half way through her pregnancy when doctors identified a 99 percent blockage in the foetal aortic valve, leakage in mitral valve and shrinkage of the left side of the heart. (Representational image )Reuters

A 25-year-old woman in Hyderabad has become the first person in the country to successfully undergo a surgery to correct certain heart defects in her unborn baby.

Sirisha, a science teacher, was half way through her pregnancy when doctors identified 99% blockage in the foetal aortic valve, leakage in mitral valve and shrinkage of the heart's left side, Bangalore Mirror reported.

Aortic valve serves as a connecting bridge between the heart and aorta, the main blood vessel that transports oxygen-rich blood from the heart to different parts of the body. It opens and closes to facilitate blood flow from the heart and prevent it from re-entering the heart.

Mitral valve, that divides the upper left chamber atria from the lower left chamber ventricles, regulates blood flow in the heart by transporting blood from the left atrium to the left ventricle and by closing the valve when the lower chamber is full. It is the left ventricle that pumps blood into the aorta.

The first surgical procedure conducted at 25 weeks of pregnancy was a failure. However, through a two and half hour long surgery conducted on 23 October, chief paediatric cardiologist Dr K Nageswara Rao and his medical team, including eight cardiac specialists and 22 assistants at the Care Hospital in Banjara Hills, operated on the 27-weeks-old foetus and reduced the blockage to 60%.

"After waiting for a good foetal position, Sirisha and the foetus were given general anaesthesia. A needle was inserted into her abdomen, which then advanced to uterus, baby's chest and finally reached left ventricle," paediatric cardiologist Sai Leela told The Hindu. The team used a wire and a tiny balloon to repair the defect.

Doctors credited the expecting mom for their achievement. "A normal course in such cases is abortion. But we suggested an intervention that could save the life of the baby. A science teacher, Sirisha courageously accepted the advice," Dr Rao, told The Hindu Business Line.

During a chat with Bangalore Mirror, he revealed his plans to repeat the procedure after the baby's birth. "I have been waiting for ten long years to perform this surgery. Though we tried one three years ago (a different case), the surgery failed and the baby died. Now, this baby will be born healthy and will be normal once the remaining part of the correction is carried out."

Sirisha, who lives with her husband Arun (29) and 20 month-old son in Injapur village of Ranga Reddy district, is now 29-weeks pregnant, and has fully recovered from the surgery. She is expected to welcome her baby in the third week of December.

Foetal Surgery- How Common is it?

Though prenatal surgeries are carried out in different parts of the world, this is the first foetal surgery to be performed in India.

Four-year-old Leyna Mykaella Gonzalez from the US is the first baby in the world to successfully undergo a surgery while in her mom's womb, according to the BBC.

In May 2010, her mother, Tammy Gonzalez, underwent a surgery at the Jackson Memorial Hospital in Miami, to remove a tumour from the baby's mouth. The case has been reported in the American Journal of Obstetrics and Gynecology.

In another case, doctors at the Children's Hospital in Philadelphia, saved the life of a baby boy by conducting a heart surgery months before his birth.

Through a statement posted on its website, the Children's Hospital of Philadelphia announced that it had already carried out 1,000 foetal surgeries, by 6 June 2013. The experts also estimated the total number of foetal surgeries around the world to 4,000 at that time.