The Shifting Burden of Body Weight for Women’s Childbearing Experiences

Michelle Frisco, Pennsylvania State University
Margaret M. Weden, RAND Corporation
Adam M. Lippert, Pennsylvania State University
Kristin Burnett, Pennsylvania State University

Clinical research indicates that obesity impedes conception. Less is understood about population-level links between weight and women’s childbearing trajectories, the social component of this association, or whether it is malleable over time. This study examines these issues. Analysis of data from the NLSY79 female sample shows how weight and childbearing trajectories are linked among two cohorts of women who experienced similar historical fertility contexts but different normative weight contexts. We find that BMI is negatively related to Cohort 1's childbearing trajectories but not Cohort 2's. These cohort differences suggest that biological factors alone do not drive the overall impact of obesity on fertility. Rather, the fertility consequences of obesity among U.S. women of childbearing age has been, and may continue to be, malleable over time and due in part to social processes.