by the process of German unification since 1989. In both parts of Berlin, geography, nutritional traditions, the degree of urbanization and industrialization, language, and genetic background were virtually identical. Both countries took pride in no-cost access to prenatal care and advanced perinatal medicine available to everybody. However, while medicine had the same scientific roots and similar traditions in both parts of Germany, social and economic systems started to differ vastly after 1945, with an ever-increasing distance after the two German states were founded in 1949 and the wall was built in 1961. Consecutively, the socio-political infrastructure and with that the organization of health care diverged progressively. After the political unification, the percentage of VLBW infants increased and the mortality of VLBW infants decreased in both parts of Germanywomen (> 35 years of age) and women who were migrants from developing countries (mostly Turkey in West Berlin, and Vietnam in East Berlin) constituted a larger proportion of the West than of the East Berlin group. The levels of both maternal and paternal education were also distributed differently in the East and West Berlin groups, with larger fractions having either low (less than 10 years) or high (12 years or more) school education in West Berlin, as opposed to East Berlin.

Factors associated with VLBW infant delivery in East and West Berlin

Separate univariate logistic models for East and West Berlin data yielded partly differing results. Among the obstetric history variables, only previous preterm delivery in East Berlin, and previous fetal loss (stillbirth or spontaneous abortion) in both sites