The Morriston Hospital consultant said incidents of cleft lip and palate were higher in India than Wales.
Drake, a consultant, said working in India had improved his skills as a maxillofacial surgeon.
Each year, he travels to India with his colleague Chris Penfold from North Wales, who works at Alder Hey Children's Hospital in Liverpool. The trips are organised by the UK-based charity the Northern Cleft Foundation.
The surgeons undertake marathon operating sessions - between 12 and 14 hours at a time - and help train local doctors.
"In India the healthcare system is basically private, and as a lot of people come from rural, agricultural backgrounds, their families can't afford the cost of the operations. There are around 35,000 babies born with a cleft lip and palate every year in India compared with just over 1,000 in the UK," he said.
"Parents in India are the same as parents the world over and only want the best for their children. Initially they are often quite shocked when they see their child following an operation. But that is followed by a huge sense of relief because they realize the massive impact on their child's future that the surgery will make," he adds.