In studies of the fertility of migrants in which the data are confined to the migrants only, estimation bias will normally appear in comparisons of childbearing before and after migration. The same issue arises in studies of union formation before and after first birth, marriage formation before...

Until the late 1980s there was little non-marital cohabitation in Romania. After the fall of state socialism, the overall fraction in consensual unions grew steadily, and by 2005 it had reached some 10%. This development had consequences for the patterns of childbearing. The present paper...