Sociology Ph.D. Dissertations


Obesity and First Birth: Timing, Union Status, And Subsequent Union Formation And Dissolution

Date of Award


Document Type


Degree Name

Doctor of Philosophy (Ph.D.)



First Advisor

I-Fen Lin (Advisor)

Second Advisor

Kelly Balistreri (Committee Member)

Third Advisor

Susan Brown (Committee Member)

Fourth Advisor

Kara Joyner (Committee Member)

Fifth Advisor

Dara R. Musher-Eizenman (Committee Member)


During the past twenty years, the United States has experienced increasing prevalence rates of obesity, especially among women of childbearing age. For adolescent girls aged 12 to 19, the obesity prevalence rate has more than doubled since 1994, and it has increased by more than 15% for women aged 20 to 39 during the same time period. Consequently, individuals of prime childbearing age are more likely to be obese than prior generations, which is likely to redefine family formation behaviors. This dissertation examines how obesity is associated with first birth, specifically timing and union status, as well as union formation and dissolution following first birth using data from the 1997-2011 rounds of the National Longitudinal Survey of Youth 1997 (NLSY97). Consistent with the physical maturation hypothesis, I found overweight and obese women experienced a first birth at younger ages compared to normal weight/underweight women. Overweight and obese women were more likely to experience a first birth than their thinner peers, but this association was weaker for minorities than for whites. Consistent with the stigma of obesity perspective, compared to normal weight/underweight women, the odds of a marital first birth were lower for obese women, but only when age a first birth was controlled. However, when economic resources were controlled, the association between obesity and union status at first birth was nonsignificant. Minority women were less likely to experience their first birth in a union, but this association somewhat varied by body weight. The odds of a marital rather than a cohabiting first birth were 68% lower for Black obese women than white normal weight/underweight women. Among women who were single at first birth, obese women had lower odds of forming a cohabiting union following a first birth than normal weight/underweight, but the association became nonsignificant once age at first birth was controlled. The association between BMI and union dissolution following first birth was nonsignificant. Taken as a whole, these findings highlight the disadvantages obese women face in family formation experiences and how race and ethnicity is an important factor to understanding such experiences.