U.S. teens are getting sex education, but most are not learning about birth control from their parents, new government data showed on Thursday.

And rates of infection with sexually transmitted diseases reflect this -- the annual rate of AIDS diagnoses for boys aged¹ 15 to 19 years has nearly doubled in the past 10 years.

The numbers show that U.S. youth need better sex education, the U.S. Centers for Disease Control and Prevention said.

The new administration of President Barack Obama has been dropping some of the more controversial policies of the former Bush government, including an emphasis on abstinence-only education.

"The data presented in this report indicate that many young persons in the United States engage in sexual risk behavior and experience negative reproductive health outcomes," the CDC wrote in its weekly report on death and disease.

For its report, the CDC compiled data from many different studies of hundreds of thousands of children and young adults aged 10 to 25.

Among 18 and 19-year-olds, 49.8 percent of girls and just 35 percent of boys had talked with a parent about methods of birth control.

More than 80 percent of boys and girls said they had received formal instruction before age 18 on how to say no to sex.

Nearly 70 percent of teen girls and 66 percent of boys had received instruction on methods of birth control.

Thirty percent of girls aged 15 to 17 reported they had engaged in sex; this rose to 70.6 of girls aged 18 to 19.

For boys, 31.6 of those aged 15 to 17 had ever had sex; 64.7 percent of those aged 18 to 19.

Nearly 10 percent of young women aged 18 to 24 said their first intercourse² was involuntary.

Infections with the human immune deficiency virus that causes AIDS rose among boys aged 15 to 19 from 1.3 cases per 100,000 in 1997 to 2.5 cases in 2006.

美国政府于上周四发布的最新调查数据称，美国的青少年在接受性教育，但大部分并不是从父母那里了解避孕知识。

性传播疾病的感染率印证了这一事实。在过去10年间，15岁至19岁的男青年艾滋病年确诊率几乎翻了一番。

美国疾病控制及预防中心称，这些数据表明，美国青少年需要接受更好的性教育。

新上任的奥巴马政府已放弃布什政府实施的某些更具争议的政策，其中包括“唯禁欲”教育政策。

美国疾病控制及预防中心在死亡与疾病周报中写道：“报告中的数据表明，美国很多年轻人有过危险性行为，并尝到过生殖健康疾病的苦果。”

为完成这份报告，美国疾病控制及预防中心汇集了针对几十万儿童和青少年进行的多种不同研究的数据，这些青少年年龄在10岁至25岁之间。

在18岁至19岁的受访者中，49.8%的女孩和仅仅35%的男孩曾与父亲或母亲谈论过避孕措施方面的话题。

超过80%的男女受访者称，在18岁前，他们接受过如何拒绝性要求的正式指导。

近70%的年轻女孩和 66%的男孩称曾接受过避孕指导。

报告称，在15岁至17岁的受访者中，有30%的女孩称曾发生性行为，而在18岁至19岁的女孩中，这一比例升至70.6%。

15岁至17岁的男孩中，31.6%的受访者曾发生性行为，在18岁至19岁的男孩中这一比例升至64.7%。

在18岁至24岁的年轻女性中，有近10%称首次性行为并非自愿。

在15岁至19岁的男孩中，可导致艾滋病的人类免疫缺陷病毒感染率从1997年的10万分之1.3升至2006年的10万分之2.5。

Vocabulary:

abstinence-only：布什政府出台的“唯禁欲”政策，号召美国青少年在婚前节制性欲，减少性病传播和少女怀孕现象。