SHANGHAI -- Shanghai couples are being encouraged to have a second child after just 4 percent filed application following the city easing its one-child policy last year, officials said Tuesday.

Brought in last March, the policy allows Shanghai couples to have a second baby if either parent is a single child.

But as of the end of 2014, only 16,600 of Shanghai's 370,000 qualifying couples had applied, Fan Hua, an official with the Shanghai Municipal Commission of Health and Family Planning, said at the municipality's annual legislative session.

The application rate, 4.59 percent, is much lower than the national average of 9 percent, which translates to nearly 1 million of 11 million qualifying couples applying for a second child last year.

"Two children are good for family stability and social development and couples that qualify are encouraged to have a second baby," Fan said, adding the municipality still needs the national guideline in place to fully lift the one-child policy.

Vice chairperson of the Shanghai Municipal Women's Federation, Zhu Ming, said the high cost of raising a child, nursing and career pressure were behind the low take up rate.

According to Zhu, to raise an infant until it turns 22 years old costs nearly 1 million yuan ($162,970) on average in Shanghai.