By Nick Thorpe
BBC News, Poland
Population levels across many parts of the developed world are declining, but this is particularly noticeable in former Eastern Bloc states where the number of children being born has plummeted within a generation.
The exception is Slovakia, where a bundle arrives every day with a postmark from the 1970s. Former Czechoslovak leader Gustav Husak keeps sending gifts.
Many people in Central Europe are now delaying having children
During his regime, cheap flats, long maternity leave and, for want of a politer word, sheer boredom, produced a baby boom. And his major boom is reproducing a minor baby boom today.
The girls conceived in the tall panel houses of the Petrzalka suburb of Bratislava, or beneath the weeping willows along the shores of the Danube, have reached the age of peak fertility. Slovakia is suddenly the only country in Central Europe where births outnumber deaths.
"Yes, it is an achievement," beams Dr Robert Paldia, deputy head of obstetrics at the Cyril and Methodius hospital, embedded deep among the high-rise towers of Petrzalka.
As populations plunge throughout the region, the plucky Slovaks are proudly producing offspring.
In an incubator in the intensive care ward on the third floor, Anna Krisztina inspects her new surroundings. Only half an hour old, born by caesarean, I see her even before her mother does.
Something to do
Boris Vano, from the Slovak Demographic Research Centre is less impressed by the numbers.
"In 1974, 100,000 babies were born in Slovakia - now barely 50,000 a year," he laments. And when the boom girls have had their baby - two if we are lucky - he foresees Slovakia slipping back into the same, shrinking population straits as the rest of Central Europe.
In the 1970s, his counterpart in Prague Jan Hartl explains, couples married on average after only three months of acquaintance. The girl was 22 and usually pregnant.
Those marriages may not have survived, but their copious young are now delaying conception until their early thirties. They have access to an arsenal of contraceptives their parents could not have dreamt of. Under Communism, abortion was the most commonly available method.
Gustav Husak's gift might have been even more substantial. The unintended children of yesterday could have had intended children today.
Another irony in Europe's formerly communist countries was that the crushing of popular resistance under the tank tracks often ended in the maternity ward.
In Hungary after the failed 1956 revolution, in Czechoslovakia after the Prague Spring in 1968 and in Poland after martial law in 1981, the birth rate rose spectacularly. It was as if the youth, frustrated in their desire for greater political freedom, took consolation in their desire for one another.
In Warsaw, Families Minister Joanna Kluzik Rostkowska is watching the calendar.
Will Joanna Kluzik Rostkowska's plans reverse a declining birth rate?
The final baby boom generation of the communist years, the class of 1983, is just beginning to think of procreation. Her conservative government is looking for ways to encourage them.
"Our research proves that Polish women still want to have babies," she explains. But they also want to carry on working.
So she has drawn up a package of measures, including increased maternity and paternity leave, tax breaks for businesses, flexibility for the self-employed and enabling workplaces to establish kindergartens and nurseries in the hope that her compatriots can be persuaded back into bed.
It is a model which appears to have succeeded in France, where the population is increasing by a quarter of a million a year.
Elsewhere in Warsaw, demographer Krystyna Iglicka says it cannot be done in Poland.
She has studied the French statistics in detail, and says the only women having lots of children in France today are immigrants. "And we don't let our immigrants stay long enough."
Poland has a growing labour shortage, as its young and skilled workers flood west, to countries like Britain and Ireland. And the latest research shows they plan to stay longer than they originally thought.
The Polish babies of the future may be born in Dublin, and Darlington.
At the other end of the demographic scale, Jan Hartl in Prague mourns the disappearance of the profession of grandparent.
In the 1970s, you became a grandparent at 45, he says. Grandparents saw their main role in life to care for their grandchildren.
Now the elderly can expect to live longer, but families are more scattered, and the children, by the time they start having children of their own, are more financially secure.
So the children sit at computer or television screens. And the line of transmission of knowledge, from the old to the very young, breaks down.
The elderly feel they have no-one to talk to.
From the park benches in Budapest and Bratislava, Prague and Warsaw, they watch, bemused, as their fellow pensioners from America and Britain, France and Austria sail past, dressed to the nines, flailing cameras and credit cards. An average pension in Hungary is $400 a month (£200; 296 euros), and many live on less.
With little to do with their time, and little money for material goods, depression is a growing problem.
"Depression, not cancer, is the scourge of our age," says Ferenc Benkovich, founder of Saint Anna's old peoples' home in Gyor, in western Hungary.
"I'm a priest, from a village, and the greatest gift of my life is that, from childhood I enjoyed the company of the elderly."
From Our Own Correspondent was broadcast on Saturday 4 August, 2007 at 1130 BST on BBC Radio 4. Please check the programme schedules for World Service transmission times.