[1] WASHINGTON UNIV, DEPT INTERN MED, ST LOUIS, MO USA
[2] TULANE UNIV, SCH MED, NEW ORLEANS, LA USA
[3] VET ADM HOSP, NEW ORLEANS, LA USA
[4] HOSP GINEC OBSTET 1, INST MEXICANO SEGURO SOCIAL, DEPT GYNECOL, GABRIEL MANCERA 222, MEXICO CITY 12, MEXICO