Whereas some arguments can be advanced suggesting that the life expectancy in east Germany should have declined directly after the fall of the Berlin Wall in 1989, other arguments suggest an increase. The aim of this study was to identify the actual developments and to explain the findings. Census data and mortality statistics from East and West Germany before unification were used to calculate standardized mortality ratios and life expectancies for various population groups. The differences in life expectancy between East and West were broken down according to age groups. The main finding was that the life expectancy of east German men declined in 1990 by 0.9 years, and only reached the 1989 level again in 1992. This was due solely to an increase in mortality for men under the age of 65. In 1990 and 1991, there were 3,400 more deaths among men under the age of 65 than would have been expected on the basis of the mortality rates of 1989. In contrast, the life expectancy of women hardly declined at all in 1990, and in 1992 it was already one year more than for 1989. The most important reasons for the increased numbers of deaths of men under the age of 45 were motor vehicle accidents, whereas ischaemic heart disease and cirrhosis of the liver were more significant for men between the ages of 45 and 65. Suicides did not increase after the fall of the Berlin Wall. It could be shown that the findings were not the results of artifacts.(ABSTRACT TRUNCATED AT 250 WORDS)