BEIJING, July 20 -- China has bolstered its birth-defect prevention system, with the country now boasting over 4,000 agencies dedicated to prenatal screening tests and more than 3,000 agencies offering pre-marital and pre-pregnancy examinations, according to a symposium on rare-disease collaboration and communication on Saturday.

The number of prenatal diagnostic institutions in China has exceeded 500, while there are 259 centers dedicated to screening newborn diseases.

Currently, there are over 8,000 identified birth defects, with a notable portion of them being classified as rare diseases, according to Shen Haiping, deputy head of the maternal and child health department of the National Health Commission.

"Enhancing the prevention and treatment of birth defects is crucial for improving the diagnosis and treatment of rare diseases," Shen said.

China has included the prevention of birth defects as a crucial element in its Outline of Healthy China 2030, and issued multiple documents to give directions for medical institutions to offer equitable, accessible, high-quality and efficient services for the prevention of birth defects.

At present, a total of 24 provinces nationwide provide free pre-marital examinations and 23 provinces offer free pre-pregnancy examinations. Thanks to the endeavors in enhancing prenatal screening, diagnosis and intervention, the prenatal screening rate has increased to 91.3 percent in China.

The infant mortality rate and the mortality rate among children under five caused by birth defects have both decreased by more than 30 percent nationwide, compared to five years ago, Shen said.

Further efforts will be made to improve the prevention and treatment of birth defects, as well as to enhance the diagnosis and treatment of rare diseases, to better fulfill the aspiration of the public to have healthy children, Shen added.