Impact of National Health Insurance on maternal health behaviors and infant health outcomes: A natural experiment in Taiwan

One important goal of a universal health insurance is to improve the health outcomes of the population. This paper aims to estimate the impact of the introduction of the National Health Insurance (NHI) in Taiwan in 1995 on maternal health behaviors and infant health outcomes. The NHI provides the same health insurance for the entire population of Taiwan, where only government employees and their dependents had similar coverage before the NHI was implemented. We pool five household-based surveys with detailed information on infant birthweight, number of prenatal care visits and other maternal health behaviors including the receipt of prenatal examinations such as ultrasound and amniocentesis; maternal cigarette smoking; and the likelihood of breastfeeding. Information on sector of employment in these surveys enables us to create control and treatment groups. We employ a difference-in-differences estimation methodology to sort out the effects of NHI from unobserved trends. We also use the interactions between county and time dummies as instruments to predict the choice of treatment status. Overall, our results suggest that the NHI has no significant impact on maternal health behaviors and infant health outcomes.