Other factors behind the decline include teens waiting longer to have sex and using more than one form of contraception during sex, according to the California Department of Public Health. Female teenagers nationwide are using contraception more 81% of those interviewed say they used birth control the first time they had sex, according to 2011-2015 data from the National Survey of Family Growth. The percentage has increased from just under 75 % since 2002. More teens are using long-acting, reversible contraceptives such as intrauterine devices and contraceptive implants. And the percentage of female teens who have used the morning-after pill tripled over that time, to nearly 1 in 4. More than half of California high schoolers reported using a condom the last time they had sex, according to the federal Centers for Disease Control and Prevention. And 30% reported relying on the birth control pill, shot, or IUD the last time they had sex. California law since 2016 has required traditional public schools to provide comprehensive sex education, based on medically accurate facts and that does not mostly stress abstaining from sex. The law was expanded to public charter schools last year. It was the first sex-ed update since 2003, when the state began requiring schools to teach students how to prevent HIV/AIDS.