Effect of universal no-cost coverage on use of long-acting reversible contraception and all prescription contraception: population based, controlled, interrupted time series analysis

Objective: To estimate effects of a policy introducing universal, no-cost public coverage for prescription contraception on use in British Columbia, Canada.

Design: Population based, controlled, interrupted time series analysis.

Setting: 10 Canadian provinces.

Participants: Prescription medications dispensed to reproductive aged (15-49 years) female residents of British Columbia, Canada, compared with a synthetic control derived from the nine other Canadian provinces and a population based cohort of 859 845 female individuals in British Columbia (age 15-49 years) between 1 April 2021 and 30 June 2024.

Intervention: Introduction of a universal contraception coverage policy in April 2023, where the public insurer pays 100% of prescription costs.

Outcome measures: Number of monthly dispensations for long-acting reversible contraception (LARC) and number of monthly dispensations for all forms of prescription contraception (including LARC), percentage of reproductive aged female residents using LARC and using all forms of prescription contraception, and the proportion of people using prescription contraception who use LARC (LARC market share). Segmented regression models were used to estimate policy effects by comparing the expected outcome values after 15 months of the policy (ie, the counterfactual, derived from trends before the policy and changes in the control) with the observed values, with 95% confidence intervals (CIs) estimated using bootstrapping.

Results: In April 2021, 3249 (95% CI 3066 to 3391) LARC prescriptions were dispensed in British Columbia, with a declining slope trend of −17 (−30 to −7) fewer dispensed per month before the policy. Monthly LARC dispensations increased by 1050 (942 to 1487) immediately after British Columbia’s policy change and saw a steady increasing trend after the policy introduction. An additional 1273 (963 to 1698) monthly LARC prescriptions were dispensed 15 months after policy implementation compared with the expected volume, representing an estimated 1.49-fold (1.34 to 1.77) increase. Dispensations for all prescription contraception (including LARC) increased by 1981 (356 to 3324) per month, representing a 1.04-fold (1.01 to 1.07) increase. Among the 859 845 female residents aged 15-49 years in the population, 9.1% were using LARC in April 2021. 15 months after the policy, 11 375 (10 273 to 13 013) more individuals were using LARC than expected without the policy, representing an additional 1.3% (1.2% to 1.5%) of the population. The policy led to an additional 1.7% (1.5% to 2.3%) of the population using any prescription contraception. 15 months after the policy, the LARC market share was 1.9% (1.2% to 2.3%) higher than expected.

Conclusions: Universal, no-cost public coverage in British Columbia increased prescription contraception use overall, driven by increased LARC use. As such, cost seems to be an important contributor to contraception use and method selection at the population level.