A total of 315 adolescent offspring participated in a follow - up study when they were 15 years old; 280 (89 %) were born to white mothers, 195 (62 %) to unmarried mothers, 151 (48 %) to mothers younger
than 19 years, and 186 (59 %) to mothers from
households of low socioeconomic status at the time of
registration during pregnancy.