Background: Korea is encountering major challenges related to its declining birth rate and aging population. Various policies have been introduced to prevent further population decrease and boost the birth rate, but their effectiveness has not been verified. Therefore, this study examined the effects of assisted reproductive technology (ART) insurance coverage on marriage, pregnancy, and childbirth in women of childbearing age.

Methods: All information on marriage, pregnancy, childbirth of women of childbearing age was obtained from Statistics Korea and Korean National Health Insurance Service database. During a total follow-up period of 54 months (July 2015 to December 2019), an average of 12,524,214 women of childbearing age per month, and 29,701 live births per month were included in the analysis. An interrupted time series with segmented regression was performed to analyze the time trend and changes in outcomes.

Results: The implementation of ART coverage policies had no significant impact on marriage or pregnancy rates. However, it did affect multiple pregnancy and multiple birth rates, which increased by 1.0% (Exp(β3) = 1.010, P-value = 0.0001) and 1.4% (Exp(β3) = 1.014, P-value = < 0.0001), respectively, compared to the pre-intervention period. Although the effect of covering ART treatment on total birth rates were not confirmed, a slightly slower decline was observed after the intervention (Exp(β1) = 0.993, P-value = < 0.0001, Exp(β1 + β3) = 0.996 P-value = 0.012).

Conclusion: This study identified the effects of ART health insurance coverage policy on the rates of multiple pregnancies and births. After the policy implementation, the downward trend in the total birth rate reduced slightly. Our findings suggest that interventions to support infertile couples should be expanded to solve the problem of low fertility rates. To address the intricate problems related to low birth rates, the Korean government introduced a policy that provides financial support and health insurance coverage for assisted reproductive technology (ART) treatment for infertile couples. As a result of evaluating the effectiveness of the ART coverage policy, it led to higher rates of pregnancies and births. In addition, although the total birth rate has been continuously decreasing over time, the decline may have been slowed down slightly by this policy.