Behind the change is improved medical care and more acceptance of hospital births. More than 90 percent of Tibetan women choose hospital births now. Tibet covers hospital costs for mothers from rural areas and offers a one-off payment of 1,000 yuan (around 150 U.S. dollars) each time they deliver in a hospital.

With 22 medical staff, the People's Hospital of Tsonyi County can treat simple illnesses and perform some surgery. Patients with severe problems still have to go to Lhasa.

"The medical situation in Tsonyi has improved a lot in recent years," said Yang. Tibetans who were once unable to afford to see a doctor, now regularly visit government clinics and hospitals.

Through a government "pairing-up" program since 1994, various provinces, municipalities, central government departments and state-owned enterprises have provided personnel, materials, financial and technological support to Tibet.

In 2002, CNPC, China's largest oil and gas producer and supplier, began to support the county, said Li Anming, director with the emergency office of CNPC Central Hospital. Affiliated hospitals started to send medical teams to the county in 2009. So far, nearly 100 doctors have volunteered to go there. Local Tibetan doctors and nurses also visit affiliated hospitals for training each year.

Hou's medical team received more than 950 patients and performed four operations, including the two caesareans, in just a week.

"Most of patients traveled over 200 km to see us. I was touched by their trust," said Huo.

Before leaving Tsonyi, Huo put the photos of the two Tibetan babies in his suitcase.

"I started missing this place before I even left, missing my 'daughter' and 'son,'" he said.