At least one in four teenage American girls, about 3.2 million, has a sexually transmitted disease (STD), suggests a first-of-its-kind federal study that startled some adolescent-health experts.

• 美国联邦疾病控制及预防中心的研究首次震惊发现，全国年龄在14岁到19岁之间的少女，至少1/4(约320万)患有性传染病。