Teenagers do not fear warts and bodily havoc caused by sexually transmitted diseases.  The ones who abstain from sex are more worried about the wrath of God.

A report by the National Center for Health Statistics that surveyed 4,662 teenagers, asked those who abstained why they had chosen not to have sex. The top reason for both males and females between the age of 15 and 19, was that sexual intercourse was “against religion or morals.”  They were least likely to be concerned about STDs.

The report on teenage sexual activities released Wednesday found that the rate of teenagers having sex has declined slightly from the last report released in 2002, but this change was not substantial.  It follows an overall trend of decline in teenage sex in the last 20 years.

The data came from the Centers for Disease Control and Prevention’s national survey.

“This study helps inform public health and to try to understand the factors behind teen pregnancy rates and birth rates,” said lead author, Gladys Martinez, a statistician at the National Center for Health Statistics.  

The report also found increases in male teens using condoms and females using injectable birth control such as Depo-Provera,  contraceptive patches at the time of their first sexual intercourse.

Here are 10 of the study’s findings by the numbers:

39.1  -  U.S. birth rate for females ages 15 to 19 in 2009. 

The birth rate of 39.1 births per 1,000 females is a historic low for the United States, which had teenage birth rates as high as 53 in 1988.  But the report points out that the teen birth rate has fluctuated in the last two decades.

The U.S. teenage birth rate remains fairly high compared with Canada, which had 14 teenage births per 1,000, Germany at 10 and Italy at 7.

43%  – female in the 15-19 range who’ve never been married, who have had sexual intercourse at least once

This percent was based on 2,284 females surveyed for the report – the largest sample ever interviewed for this type of report.

“Overall, in the 20-year period from 1988 through 2006–2010, the percentage of teenaged females who were sexually experienced declined significantly (from 51% in 1988 to 43% in 2006–2010),” according to the report.

Historically, black female teenagers were more likely to be sexually experienced than Latinos and whites.  The rate of sexual experience was 57% for black teenagers in 2002, but has now dropped to 46%.

Because of that decrease, “now we don’t see a racial difference” among female teenagers, said Martinez.

42% –  males 15-19, who’ve never been married, who have had sexual intercourse at least once

This percent was based on 2,378 males surveyed.

Unlike the females, the racial differences in teenage sexual experiences are still present.

“Black teenagers had significantly higher percentages sexually active (38%) compared with both Hispanic (30%) and non-Hispanic white (25%) teenagers,” according to the report.

41% - female teenagers who say they abstained because of religious or moral reasons

For males, 31% of them cited this reason. The second most common reason for males was that they hadn’t “found the right person yet,” followed by the fear of getting a girl pregnant.

For females, their second most common answer was that they didn’t want to get pregnant followed by not having found the right person yet.

50 - percentage of total  U.S. STD cases that occur in the 15-24 age group

While teenagers and young adults in this age group represent only about a quarter of the population, they comprise 50% of all new STD cases.

Females between the ages of 15  and 19 have the highest rates of chlamydia and gonorrhea.

53- 54% - the percent of teenagers who've had sex and come from single-parent home

“If the teenagers have been raised with both parents, they’re less likely to have sex,” Martinez said.

The data have shown for years that teenage sexual activity differs between family structures.  Teens raised in families with two parents are 35% likely to have sex during ages 15 to 19.

18% - girls who had their first sexual intercourse under the age of 14 who didn’t want it to happen

At the same time, 30% of the teens who had sex before they turned 14, said they wanted the intercourse to happen. The remainder reported mixed feelings.