Trends in Sexual Initiation and Contraception Use Among Czech Adolescents between 2002-2022

Objectives: This study examined trends in sexual behaviour and the timing of sexual initiation among 15-year-old adolescents in Czechia between 2002 and 2022, with a focus on the age of sexual debut (i.e., 15 and older; early at 14; very early at 13 or younger). It also investigated trends in condom and hormonal contraceptive use at most recent intercourse. Methods: Data were drawn from six nationally representative waves of the Czech Health Behaviour in School-aged Children study, which was conducted between 2002 and 2022. Only 15-year-olds were included (N = 19,384). Descriptive trend analyses were conducted using survey weights, with subgroup comparisons by gender and age at sexual initiation. Results: The findings indicate a shift toward later sexual initiation, particularly among girls, with increasing proportions initiating at age 15 or older and declining initiation at age 14. A significant gender gap emerged in 2022, with fewer girls (13.9%) than boys (18.7%) reporting a sexual experience. The prevalence of very early initiation (age 13 or younger) remained stable over time, yet this group—especially boys—consistently accounted for a substantial minority of sexually active adolescents. Condom use declined from 81.2% to 69.9% across all initiation groups between 2014 and 2022, with the most persistent decline among very early initiators. Conclusions: The findings suggest a modest postponement of sexual debut among Czech adolescents and highlight a growing gender disparity in sexual activity by age 15. Persistent early initiation and declining condom use highlight the need for differentiated sexual health education strategies, particularly for younger initiators.