Teens' contraceptive use marked by inconsistency.
D000569:Americas; D001519:Behavior; D003267:Contraception; D003268:Contraception Behavior; D003710:Demography; D019049:Developed Countries; D005193:Family Planning Services; D005298:Fertility; D009656:North America; D011153:Population; D011157:Population Dynamics; D011247:Pregnancy; D011253:Pregnancy in Adolescence; D012725:Sexual Behavior; D014481:United States
Adolescent Pregnancy; Americas; Behavior; Contraception; Contraceptive Usage; Demographic Factors; Developed Countries; Family Planning; Fertility; North America; Northern America; Population; Population Dynamics; Pregnancy, Unplanned; Reproductive Behavior; Sex Behavior; Technical Report; United States