The birth defect rate in China has increased over 70 percent from 87.7 per 10,000 in 1996 to 149.9 per 10,000 in 2010, the Ministry of Health said in a report on Wednesday.

Congenital heart disease, hyperdactylism, cleft lip with or without cleft palate, congenital hydrocephalus, and neural tube defects account for 49.1 percent of the total defects, surveillance data from hospitals in 2010 revealed.

Qin Huaijin, a senior official from the MOH, said the rate's rise in recent years was caused by various factors, including environmental changes and a reluctance to undergo premarital health check-ups.

Children born with birth defects and learning difficulties average 1.2 million out of the 20 million new born babies each year in China, said Bian Xuming, director of the maternity department of Peking Union Medical College Hospital.

Meanwhile, maternal and infant death rates in China have dropped sharply over the past decade, according to the Report on Women and Children's Health Development, which was released on Wednesday by the Ministry of Health; the first of its kind in China.

The maternal mortality rate stood at 30 per 100,000 in 2010, down 43.4 percent from 2000's mortality rate, Xinhua news agency reported, citing Qin Huaijin.

The infant mortality rate was 13.1 per 1,000 in 2010, dropping 59.3 percent from 2000, while the mortality rate for children under five fell 58.7 percent to 16.4 per 1,000 in 2010.

However, due to China's massive population, the reduced mortality rates still indicate that 209,000 infants and 261,000 children under five died last year, the report said.

The report lists five main causes of child mortality, including premature birth, congenital heart disease and accidental asphyxia, China Daily reports.