After the Berlin Wall fell, hundreds of thousands of people fled the former communist east for a better life in the west and an overwhelming number of them were young women.
The result, 20 years on, is one of the worst demographic imbalances in the whole of Europe which threatens the future of entire German regions, especially in the northeast.
Experts fear that the female exodus might indirectly fuel a rise of far-right extremism among bored young men, many of whom lack education and job prospects - and a girlfriend.
Between 1991 and 2005, as many as 400,000 eastern German women under the age of 30 moved west across the former Iron Curtain, compared to "only" 273,000 young men under 30.
This has led now to a situation in some northeastern villages in which there are just 45 women for every 100 men.
In 60 eastern German towns with more than 5,000 inhabitants, there are just 80 women for 100 men in the 18 to 29 age bracket, said Steffen Kroehnert of the Berlin Institute for Population and Development.
"The problem is worse in eastern Germany than even in areas of northern Finland or Sweden which have long seen an exodus of women," he added.
The problem is starkly evident in the small northeastern town of Wittstock, halfway between Berlin and Hamburg, which in two years up to 2008 saw 436 citizens aged between six and 26 leave out of a youth population of only 3,181. Of these, 54 per cent were female and 46 per cent male.
"Young people go to train elsewhere. After their studies, they don't come back," according to one of the women responsible for youth services in the town.
"Local economic activity is geared to agriculture and offers little prospects to women with higher education," she added.
And indeed, in the former communist east, only seven percent of girls left school without a diploma, compared to 15 per cent of boys, said Mr Kroehnert.
"That's one of the reasons why young women leave, because a diploma gives them more freedom to settle elsewhere. Young men, many of them unqualified, often stay where they were born," he said. Women were the first to be hit by growing unemployment in eastern Germany after the fall of the Berlin Wall but the trend has changed more recently and there are now more men than women out of work.
But this hasn't stopped the women from deserting their homelands.
Until the country reunified in 1990, "all the women in the former GDR (East Germany) worked. There was a system of creches and it was considered normal that they earned the same amount as men," according to Dagmar Bischof, president of the Business and Professional Women (BPW) network.
"Today the women of eastern Germany are still different from those in the west because they want to combine motherhood with a full-time job," according to sociologist Anne Biernat. One of the biggest problems caused by the demographic imbalance is that young eastern German men are struggling to find potential marriage partners.
In the small town of Freital, near Dresden, in southeastern Germany, mayor Klaus Maettig advertised to attract women, offering €2,000 to those who settled in the town, along with help in finding a job.
But the idea was ditched after local women protested at what they saw as unequal treatment.
Some sociologists now fear the emergence in some regions of a "male proletariat" of young men who might be attracted to extreme political parties, especially the far-right.
"When you look at the lives of young neo-Nazis you realise that it's when they find a girlfriend that they drop out of such peer groups," according to a local councillor.