Dr Robert Edwards, 85, was named winner of the Nobel Prize for Medicine on Monday for his work on in-vitro fertilisation (IVF), which has helped millions of infertile couples around the world have children.
Edwards' work led to the birth of the world's first test tube baby, Louise Brown, in Britain on July 25, 1978. Since then, 4 million babies have been born using the IVF technique.
"His contributions represent a milestone in the development of modern medicine," the Nobel Assembly at the Karolinska Institute, Stockholm which selects the Nobel Prize winner for Medicine, said.
If Louise Brown was the first test tube baby, the second was created in India only 67 days later. But the event was mired in controversy.
According to the Indian Council of Medical Research, the baby was born on October 3, 1978, in Kolkata, but Dr Subhash Mukhopadhyay's effort was not initially accepted as an IVF procedure, as it was not scientifically documented.
The first validated IVF baby in India was born eight years later on August 6, 1986.
Dr Indira Hinduja used the technique for the birth of Harsha Chawda at the KEM Hospital in Mumbai. Infertility affects one in 10 couples worldwide, of whom an estimated 19-20 million live in India, according to the World Health Organisation.
The IVF procedure involves extracting an egg from a woman and fertilising it in a lab-dish with a donated sperm. When the egg divides and develops into an early-stage embryo, it is inserted into the uterus to grow into a baby.
The treatment does not promise 100 per cent success, with just about 25 to 30 per cent of fertilised eggs leading to childbirth. Long-term follow-up studies have shown that IVF children are as healthy as other children.