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Updated: Jan 20, 2026

Chronic Social Defeat Stress in Early Adolescent Male Mice
Published on: January 24, 2025
Trends in sexual initiation and contraception use among Czech adolescents between 2002-2022
Anna Ševčíková1, Vít Suchý1, Peter Kolarčik2,3
1Psychology Research Institute, Faculty of Social Studies, Masaryk University, Brno, Czech Republic.
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 (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.
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