Seventeen test-tube babies have gathered at Tangdu Hospital of the 4th Military Medical University in Xi'an, capital city of northwest China's Shaanxi Province, to celebrate the medical institution's advances in assisted reproductive technology.

An American test-tube pigeon pair, Doudou and Miaomiao, receive a physical checkup on Saturday, September 19, 2009, at Tangdu Hospital in Xi'an, where they were born in 2005. [Sanqindaily.com]

A report in the local newspaper Sanqin Daily quoted Wang Xiaohong, an expert on reproductive technology, as saying the hospital's doctors have assisted with the births of 1,069 test-tube babies since September 1999 and have made great strides towards adopting international standards for the practice.

Of the hospital's test-tube babies, the oldest one is now nine years old and the youngest two months old. All the test-tube babies underwent physical checkups last weekend, including brain X-rays, cardiograms and tests for bone mineral density.

An American pigeon pair, Doudou and Miaomiao, received most of the attention at the hospital gathering. Their parents are an American couple working in Xi'an. The wife underwent an in vitro fertilization operation in November 2004 since the couple failed to conceive after they got married in 2002. She became pregnant within a month after the medical procedure, and her male and female set of twins was born in September 2005.