Contraceptive preferences transitioning from adolescence to adulthood

Abstract

Abstract

Background: Contraceptive preferences and behavior are known to change over time, yet few studies follow individuals longitudinally from adolescence into adulthood. This thesis investigates such transitions using data from the Fit Futures study, which includes three survey rounds conducted over a twelve-year period (2010-2022).

Objective: To describe trends and shifts in contraceptive use among female participants from adolescence (median age 16) to early adulthood (median age 27), and to explore changes in method preference over time.

Methods: This descriptive study used self-reported data on contraceptive use from 584 female participants across Fit Futures 1, 2, and 3 (FF1–FF3). Contraceptive use was categorized by method type and hormonal content for each timepoint. A subgroup of 297 participants who responded at all three time points were used for longitudinal analysis. Trends in method use and transitions over time were analyzed using descriptive statistics and visualized using a Sankey diagram.

Results: The proportion of contraceptive users increased from 37% in FF1 to 67% in FF3. Oral contraceptives (both combined and gestagen-only) remained the most used method at all time points, though their use declined slightly in FF3 as long-acting reversible contraceptives (LARCs), such as implants and intrauterine devices (IUDs), gained popularity. In FF3, 25% of participants reported using a LARC. There was also a clear shift away from combined hormonal contraceptives (CHCs) to gestagen-only methods, with gestagen-only increasing from 13% of hormonal contraceptive users in FF1 to 56% in FF3. Within the subgroup of consistent participants, transitions were common: 51% of users in FF2 had not used contraception in FF1, and 24% of FF2 users stopped using contraception by FF3. 11% reported never using contraception at any point during the study. While usage trends in the subgroup reflected the full sample, potential selection bias should be considered. It’s also important to note that FF1 and FF2 were conducted before the 2015 introduction of national reimbursement for LARCs, which may partly explain the lower use of these methods in earlier survey rounds.

Conclusion: Contraceptive use increased over time, with a marked shift toward gestagen-only methods and LARCs in early adulthood. The trends suggest changing needs and preferences as participants got older. This underscores the need for accessible and flexible contraceptive counseling during the transition from adolescence to adulthood. Comparisons with findings from other studies, covering periods both before and after the Fit Futures surveys, suggest broader time trends in contraceptive behaviour, potentially influenced by policy changes and shifting cultural attitudes. Future research should continue to explore reasoning for method choices and transitions, especially in the context of growing interest in hormone-free alternatives and the discourse around hormonal contraception.

Keywords: contraception, Norwegian adolescents, adulthood, longitudinal study, gestagen-only, oral contraceptives, LARC, Fit Futures