Caution: premarital cohabitation may be hazardous to your marriage. At least, that's what seemed to be the conclusion of a study of 4,996 Swedish women ages 20 to 44, conducted for the National Bureau of Economic Research, a Cambridge, Mass., think tank. The report found that couples who had lived together and then wedded were 80% as likely to separate or divorce as those who had lived apart.
What may skew the poll's results is the fact that two-thirds of all Swedish couples have lived together before marriage; among the young, the level is almost 90%. (Although there are no reliable...