Evaluation of psychosocial measures for understanding weight-related behaviors in pregnant women.

The greatest weight gain for US. women occurs during the childbearing years of 25 to 34, and many obese women attribute their adult weight gain to childbearing. Few studies have examined psychosocial influences on women's behaviors during pregnancy, in part because of the lack of valid and reliable measures of psychosocial constructs relevant to pregnant women. Based on existing theory and an in-depth interview study, the psychosocial constructs of locus of control, self-efficacy, body image, feelings about motherhood, and career orientation were identified. Scales for each construct were constructed by drawing items from existing validated scales and writing items based on the in-depth interviews; their content validity assessed using factor analysis with oblique rotation and their reliability using Cronbach's alpha. Construct validity was assessed by examining the associations between scale scores and preexisting conditions of participants. Data for evaluating the scales came from a study of 622 pregnant women in a rural health care system who completed questionnaires and whose medical records were audited. Cronbach's alpha of the scales ranged from 0.73 to 0.89. Scale scores were strongly associated with lifestyle behaviors, body weight, and demographic characteristics of the participants. The analysis provides evidence of the validity of measures of psychosocial factors related to health behaviors of pregnant women. These measures should be useful in studying weight-related behaviors in pregnant women.