The second half of the 20^th century saw a dramatic increase in women’s participation in the labor market. Statistics from last decade, however, suggests that the labor force participation rate of married mothers with young children decreased during the last decade after reaching the peak in the 1990s. Media attributed the recent drop in women’s labor force participation working women ‘opting out’ – leaving their professional career to become stay-at-home mothers for full time childrearing. However, some social scientists argue that they do not yet have a clear answer to this recent change in the trend of mothers’ employment

Women’s labor force attachment is an important public policy consideration for multiple reasons. Many previous studies suggest that once working mothers leave the labor market, re-entering the workforce becomes difficult. It is also well known that it is hard to continue at a similar job level or position as where they left off. Moreover, work interruptions can have a significant, negative impact on a woman’s earnings when she returns to the labor force; career exit is attributed to be one of the major contributions to the large gender gap in lifetime earnings.

Despite the importance of this issue from the public policy standpoint, it appears there is less discussion on the broader population of working mothers. The existing work has focused almost exclusively on high-skilled female professionals leaving the workforce. A woman’s first childbirth is an interesting event to study her labor supply, as she has to figure out how to combine work and childcare responsibilities. This paper contributes to the exiting literature by documenting the behaviors of labor market attachment of new mothers from a nationally representative cohort. In particular, it focuses explicitly on women’s exits and returns around the timing of their first childbirth using the National Longitudinal Survey of Youth (NLSY79) and examines whether there are systematic differences in these behaviors.