Around 8000 babies are aborted each year by married women, with more than half saying they already had enough children, the Sunday Times said.

Another 6000 abortions are performed each year on single women.

One in four women said that financial constraints and emotional exhaustion held them back from having more children, the paper said, quoting health ministry sources.

"By the time the third child comes along, parents who have limited financial resources and who feel they cannot give it the best of everything may decide to abort," said social worker Chua Wei Leng.

The government last year announced a slew of monetary incentives worth s$260 million (us$144 million) to encourage Singaporeans to have two or more kids.

"If their decision to terminate is solely monetary, how much is the state prepared to pay," said Dana Lam-Teo, president of the Association of Women for Action and Research.

Earlier this year, the city-state's founding father Lee Kuan Yew urged educated women to give birth to three children to help maintain a hard core of native Singaporeans.

Singapore's birth rate has fallen from an ideal 50,000 in 1991 to 42,000 last year which is not enough to replace the population.

Immigration could counter for the loss but "natural replacement is better," Lee had said.

Singapore's population passed the four-million mark for the first time in 2000 with foreigners accounting for close to half of the nearly one million increase since 1990.

Starting a family has taken a backseat for Singaporeans who placed career and making money their top priorities.