National Health Statistics Reports, Number 104, June 22, 2017

Recent sexual activity 

Recency of sexual activity is an 

important component for monitoring the 

risk of pregnancy and STIs. Having had 

sex in the past 3 months or past 12 months 

are commonly used indicators of “current” 

exposure, and having had sex in the past 

3 months is commonly used to define the 

“sexually active” population at a given 

point in time. 

As shown in 

Table 5

, in 2011–2015, 

38.9% of female teenagers and 39.5% 

of male teenagers had sexual intercourse 

at least once in the past 12 months. This 

prevalence did not change significantly 

from 2002 for male and female teenagers. 

Regarding the percentage who were 

sexually active (had sex) in the past 3 

months, no significant change was seen 

between 2002 and 2011–2015 for male 

teenagers. Among female teenagers, the 

percentage decreased between 2002 and 

2006–2010, from 35.7% to 31.3%, while 

no significant change occurred thereafter 

(30.2% in 2011–2015). Among female 

teenagers, the percentage who were 

sexually active in 2011–2015 varied little 

among Hispanic, non-Hispanic white, 

and non-Hispanic black females. For 

male teenagers, however, non-Hispanic 

black teenagers had higher percentages of 

those who were sexually active (39.9%) 

compared with both Hispanic (28.2%) and 

non-Hispanic white (27.8%) teenagers.

Male and female teenagers aged 

18–19 were more than twice as likely to 

have had sex in the past 3 months and 

within the past 12 months compared 

with teenagers aged 15–17. For 

female teenagers living in a household 

with both parents present, a smaller 

percentage—19.0%—had had sex in 

the past 3 months compared with 31.3% 

and 33.9% for those from both step-

parent and single-parent households, 

respectively. For male teenagers, 

having a mother who gave birth to her 

first child during her teen years was 

associated with a significantly higher 

percentage who were sexually active. 

For male teenagers whose mothers had 

less than a high school degree, 33.6% 

were sexually active compared with 

those whose mothers had at least some 

college (25.9%).