Abstract: Motherhood penalty is an important issue in the research field of family and gender inequality. China has experienced rapid economic growth and drastic social changes in recent decades, but existing studies fail to provide an overview of changes in motherhood penalty during this period. This paper uses the data from the China Health and Nutrition Survey(CHNS) from 1989 to 2015, and applies a multilevel mixed effect model to study the intensity of motherhood penalty and the various mechanisms that affect it over the period. The study shows:(1) Childbirth has a negative impact on female wages and its intensity continues to increase, showing motherhood penalty has strengthened over the time;(2) Although initially motherhood penalty is lower for single mothers than for married ones; it increases for both groups of women over the period. However, the rate of change is much faster for single mothers, and thus the difference between the two groups in motherhood penalty has narrowed gradually over the time; (3)The long-term effect of motherhood penalty is normally less weighty than the short-term effect, however, it has grown at much quicker rate over the years than the latter. In more recent years, these two effects are almost the same; (4) The higher the education level of women, the lower the motherhood penalty. However, as the penalty had intensified over the period, the difference among different educational levels has decreased;(5) Motherhood penalty for female employees in the non-state sector is greater than that of female employees in the state sector. The effect of the penalty on female employees in the non-state sector has increased rapidly, while the change has remained slow in the state sector, resulting in a widening gap between the two sectors. This study shows that the dramatic social and economic change in recent decades has placed women under greater and greater maternal responsibilities but has rewarded them disproportionately fewer benefits of the economic development.

Key words: motherhood penalty, earnings, women, employment