TY - JOUR A1 - Olsen, J. A1 - Schmidt, M.M. A1 - Christensen, K. T1 - Evaluation of nature-nurture impact on reproductive health using half-siblings Y1 - 1997 DO - 10.1097/00001648-199701000-00001 JF - Epidemiology VL - 8 IS - 1 SP - 6 EP - -11 ER -