Letter: Contraceptive practice and unplanned pregnancy in students.
D000367:Age Factors; D003268:Contraception Behavior; D003276:Contraceptives, Oral; D004739:England; D005260:Female; D006801:Humans; D011247:Pregnancy; D011275:Pregnancy, Unwanted; D013334:Students
D003276:Contraceptives, Oral