An extensive body of work shows that women experience a wage loss of approximately 5-10% per child after they become mothers. Sociologists refer to this as the motherhood penalty. Birth intention, whether or not a birth was wanted at the time of conception, has been extensively studied within demography and public health, but has not been explored as a potential contributor to the motherhood penalty. Women often spend substantial portions of their lives trying to avoid unintended births, suggesting that women themselves recognize that family planning and contraception are tools for achieving their educational or career goals. We will use panel data from the National Longitudinal Survey of Youth to analyze whether, and, if so, why, the motherhood penalty varies according to whether a birth is wanted, unwanted or mistimed. In addition, we will assess whether the impact of birth intention on the motherhood penalty varies across socioeconomic strata.