(Reuters Health) – Formal instruction about birth control and other aspects of sexual health in the U.S. is on the decline, according to an analysis of survey data from 2006 to 2013. “The declines in formal sex education we observed since 2006 are distressing, but unfortunately are part of a longer term retreat from sex education, especially instruction about birth control methods,” said lead study author Laura Duberstein Lindberg of The Guttmacher Institute in New York. “For example, in 1995 more than four out of five teens were taught about birth control—in the most recent data this is only about half,” she said. The researchers used interviews taken from nationwide household surveys administered continuously between 2006 and 2010 and between 2011 and 2013, focusing on respondents aged 15 to 19 years.