Contraceptive usage among teenagers.
D000028:Abortion, Induced; D000293:Adolescent; D003276:Contraceptives, Oral; D004363:Drug Utilization; D005193:Family Planning Services; D005260:Female; D005500:Follow-Up Studies; D006769:Hospitals, General; D006801:Humans; D007434:Intrauterine Devices; D010044:Outpatient Clinics, Hospital; D010414:Pennsylvania; D011181:Postnatal Care; D011247:Pregnancy; D011275:Pregnancy, Unwanted; D011295:Prenatal Care; D012959:Socioeconomic Factors; D013223:Statistics as Topic
D003276:Contraceptives, Oral