TOKYO (AFP) ― East Asia’s booming economies have for years been the envy of the world, but a shortfall in one crucial area ― babies ― threatens to render yesterday’s tigers toothless.

Some of the world’s lowest birth rates look set to slash labor forces in Singapore, South Korea and Taiwan, where fewer workers will support more retirees and their ballooning health care and pension costs.

Shuffling along in the vanguard of ageing Asia is Japan, whose population started slowly shrinking three years ago, and where almost a quarter of people are over 65 while children make up just 13 percent.

On current trends, Japan’s population of 127 million will by 2055 shrivel to 90 million, its level when it kicked off its post-war boom in 1955, warns the National Institute of Population and Social Security Research.

Asian population giant China may still be near its prime, with armies of young rural workers flocking to its factories. But, thanks to the 30-year-old one-child policy, its demographic timebomb is also ticking.

“Over the past 50 years, economic and social modernization in Asia has been accompanied by a remarkable drop in birth rates,” the Hawaii-based think-tank the East-West Center says in a new research paper.

“Gains in education, employment and living standards, combined with dramatic breakthroughs in health and family-planning technology, have led to lower fertility in every country of the region.”

Falling fertility rates are a common trend for societies as they grow richer, and many European nations are also below the level needed to keep a population stable ― about 2.1 children per woman over her lifetime.

While in traditional rural societies children tend to take over the farm and care for their elderly parents, in modern, urban societies, many couples, with better access to birth control, see offspring as an unaffordable luxury.

China now has 1.6 births per woman, Singapore has 1.2 and South Korea has slightly fewer than 1.1. Taiwan has just 1.03 births per woman.

One way to counter declining populations is to allow more immigration ― but governments from Singapore to Tokyo have been reluctant to do so.

At the same time Singaporeans, who have turned their city-state into an Asian hub of commerce and service industries, have long been famously disinclined to procreate.

The government has for years put on match-making events for university graduates on the assumption that Singapore’s best and brightest could be coaxed into producing a generation of brainy offspring.

While that model in social engineering has failed to bring a baby boom, bureaucrats across the region have sought to tweak policies and tax codes to get more couples in the mood, but seldom with great success.

At the core of the problem, say analysts, have been gender attitudes steeped in Confucian traditions ― with men still expecting their wives to handle the childcare and household chores that may not top a modern woman’s wish list.

Kim Hye-young, researcher at the Korea Women’s Development Institute, said: “The big problem is that South Korean women, compared to men, have too much to lose when getting married in this system.

“This reality makes marriage, let alone having a child, look like a very unattractive option in South Korea, perhaps far more so than in other countries,” she said.

In Japan, where women remain woefully under-represented in corporate boardrooms, falling pregnant still all too often spells career death.

“Women are voting with their wombs, refraining from having children because the opportunity costs are so high and rigid employment policies make many of them choose between raising a family or pursuing a career,” writes Jeff Kingston, director of Asian Studies at Temple University in Tokyo.

Other factors also play a role, he writes in a new book on contemporary Japan: many young people ― unlike their jobs-for-life fathers ― now skip between temporary jobs and lack the financial security to start a family.

Compounding the geriatric trend in Japan are long life expectancies ― a world-record 86.44 years for women and 79.59 years for men.

This means the social welfare burden is growing for a government that already has a debt-to-GDP ration nearing 200 percent, the rich world’s highest.