近日，加拿大英属哥伦比亚大学Michael R Law团队研究了全民免费覆盖对长效可逆避孕和所有处方避孕使用情况的影响。2025年7月28日，《英国医学杂志》发表了这一成果。

为了估计在加拿大不列颠哥伦比亚省推行的一项政策对处方药避孕使用的普遍、无成本公共覆盖的影响，研究组在加拿大的10个省进行了一项基于人口、对照、中断的时间序列分析。2021年4月1日至2024年6月30日期间，向加拿大不列颠哥伦比亚省育龄期（15-49岁）女性居民发放的处方药，与来自加拿大其他九个省份的合成对照组以及不列颠哥伦比亚省859845名女性个体（15-49岁）的基于人群的队列进行了比较。

2023年4月实施全民避孕覆盖政策，由公共保险公司支付100%的处方费用。观察指标为长效可逆避孕（LARC）和所有形式处方避孕（包括LARC）的月用量、育龄女性居民使用LARC和使用所有形式处方避孕的百分比、使用处方避孕的人群中使用LARC的比例（LARC市场份额）。通过比较政策实施15个月后的预期结果值（即，从政策实施前的趋势和控制变化中得出的反事实值）与观测值，使用自举估计95%置信区间（CI），使用分段回归模型来估计政策效果。

2021年4月，不列颠哥伦比亚省共发放了3249（95%置信区间[CI]为3066至3391）份长效可逆避孕（LARC）处方，在政策实施前，每月发放量呈下降趋势，每月减少17（30至7）份。不列颠哥伦比亚省政策变更后，LARC的月发放量立即增加了1050（942至1487）份，并在政策出台后呈现稳步增长趋势。与预期数量相比，政策实施15个月后，LARC的月发放量额外增加了1273（963至1698）份，估计增长了1.49倍（1.34至1.77）。

所有处方避孕（包括LARC）的月发放量增加了1981（356至3324）份，增长了1.04倍（1.01至1.07）。在人口中859845名15至49岁的女性居民中，2021年4月有9.1%使用LARC。政策实施15个月后，使用LARC的人数比无政策情况下的预期值多出11375（10273至13013）人，相当于人口额外增加了1.3%（1.2%至1.5%）。该政策导致使用任何处方避孕的人口额外增加了1.7%（1.5%至2.3%）。政策实施15个月后，LARC的市场份额比预期值高出1.9%（1.2%至2.3%）。

研究结果表明，由于LARC使用的增加，不列颠哥伦比亚省普遍的、无成本的公共保险增加了处方避孕的总体使用。因此，在人口水平上，成本似乎是避孕使用和方法选择的重要因素。

附：英文原文

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

Author: Laura Schummers, Lucy Cheng, Martin Odendaal, Elisabet Rodriguez-Llorian, I Fan Kuo, Wendy V Norman, Amanda Black, Andrea Stucchi, Mary Helmer-Smith, Elizabeth Nethery, Amanda Downey, G Emmanuel Guindon, Kim McGrail, Erin A Brennand, Sabrina Lee, Amy Metcalfe, Stirling Bryan, Elizabeth K Darling, Stefania Bertazzon, Vanessa Poliquin, Nathan C Nickel, Fiona Clement, Michael R Law

Issue&Volume: 2025/07/28

Abstract:

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 859845 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 859845 female residents aged 15-49 years in the population, 9.1% were using LARC in April 2021. 15 months after the policy, 11375 (10273 to 13013) 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.

DOI: 10.1136/bmj-2024-083874

Source: https://www.bmj.com/content/390/bmj-2024-083874