Falling population rates in Eastern Europe ever since the fall of communism will aggravate the problem of an aging population in the enlarged European Union, experts said.
Until the end of the 1980s the eight ex-communist East European countries due to join the EU in 2004 had higher birth rates than their western neighbors.
They now have large, mainly young workforces, but the brutal transition to a market economy has brought with it falling birth rates - a worrying development for the region's future.
Poland, which has the largest population in Eastern Europe with 38.3 million inhabitants, has already lost 1 million inhabitants in four years and is expected to have a population of just 34 million in 2050, according to the Population Reference Office, a U.S.-based demographic institute.
By that time, Estonia's population will have dropped by 36 percent and Hungary, which currently has a 10.1 million population, will have lost a fifth of its inhabitants.
"The European Union will age even more quickly after the eastern countries are included, because the demographic drop is bigger there. These countries are seeing a process which will be visible here in 30 years," German demographic analyst Rainer Muenz said.
All the countries in the region have birth rates of less than 1.5 children per woman, including strongly Catholic Poland, which still had 2.5 children per woman in the mid-1980s.
At the end of the 1990s Slovenia, the Czech Republic and Latvia had the lowest birth rates in the world.
Slovakia saw 55,400 births in 2000, compared with 80,400 in 1990 - a drop of more than 30 percent. A study by the Center for Demographic Research in Bratislava said the average age of the Slovakian population would climb from 36 in 2001 to nearly 48 in 2050.
In these countries, where unemployment is making new records, "bringing children into the world carries with it a very high risk of falling into poverty," explained Zsuzsa Karpati, a member of the Hungarian parliamentary commission on health.
"Under communism homes were distributed according to the number of children, women's employment was guaranteed, and there were plenty of crèches and nursery schools," but social systems have collapsed during the economic transition, said demographic expert Heinz Fassmann.
In a report on the demographic consequences of EU enlargement he said that the aging population would cause serious problems for pension systems and social security financing.
Paradoxically, the crumbling population is not worrying the general public in Eastern Europe - with the exception of Hungary, one of the few countries addressing the problem.
In autumn Hungary's Socialist government increased family grants by 20 percent and nearly doubled grants to help families with children build their own homes.
Elsewhere, worries about falling birth rates mainly affect conservative groups. Poland's Catholic Church regularly slams new Western ways of life, which it blames for the decline.