Abstract: Many countries vary in their regulations regarding premarital health examinations, which is a form of information disclosure. To examine how premarital health examinations aect marriage quality and children’s health, we exploit a policy shock in China that changes premarital health examinations from mandatory to voluntary. Consistent with our theoretical predictions, this policy shock significantly increases the marriage probability while decreasing positive assortative matching in health among married couples. We also find an increase in low birth weight rates after the policy shock. Our findings suggest that mandatory premarital examination is bene cial in promoting the quality of marriage and children’s health.