The economic consequences of unwed motherhood: using twin births as a natural experiment.
利用双胞胎出生作为意外生育的自然实验，比较未婚女性意外生育头胎与单胎头胎的经济后果，发现短期影响显著，但长期影响因种族而异。
Social scientists have long concluded that premarital childbearing exacerbates problems of both poverty and family instability. Out-of-wedlock and adolescent childbearing may reduce a mothers educational attainment lower the probability of her eventual marriage increase her probability of welfare recipiency and decrease family income. The authors use an exogenous fertility event the birth of twins to estimate the economic effects of unplanned births. The approach compares the economic outcomes of women experiencing premarital twin first births to those experiencing premarital single first births in the attempt to identify the consequences of an unplanned birth upon womens future fertility and marital decisions education labor force participation labor earnings welfare receipt and poverty status. 1970 and 1980 US Census micro data are used to identify twin births to unmarried women. Analysis found large short-term effects of unplanned births on labor-force participation poverty and welfare recipiency among unwed mothers but not among married mothers. Furthermore most adverse economic effects of unplanned motherhood dissipate over time for whites but larger and more persistent negative effects weigh upon black unwed mothers.