Demographic and social-cognitive factors associated with gestational weight gain in an Australian pregnancy cohort

AIM: To identify and describe the demographic and social-cognitive factors associated with excessive gestational weight gain using the Weight-Related Behaviours Questionnaire, within an Australian pregnancy cohort. BACKGROUND: Supporting women to achieve optimal weight gain in pregnancy is complex. Social-cognitive factors are recognised antecedents to, and mediators of, weight related behaviour change. Less is known about their role during pregnancy. METHODS: 159 women enrolled in a pregnancy cohort study completed the Weight-Related Behaviours Questionnaire (WRBQ) at approximately 19 weeks gestation, and total gestational weight gain was later measured at 36 weeks. Summary scores were reported descriptively. Multivariable logistic regression was used to test demographic (maternal age, pre pregnancy body mass index, parity, smoking status, marital status, education) and social-cognitive factors (weight locus of control, self- efficacy, attitudes towards weight gain, body image, feelings about motherhood, career orientation) as predictors of excessive gestational weight gain.FINDINGS: Maternal age was the sole demographic factor predictive of excessive gestational weight gain. Older participants (34-41 yrs) were less likely to gain excessive weight when compare to younger participants (18-24 yrs): Odds Ratio 0.20, 95% Confidence Interval 0.05, 0.82. Body image (measured as personal satisfaction and perception of own weight) was the sole social-cognitive factor associated with excessive gestational weight gain. For every one unit improvement in body image score, there was a 33% decreased odds of excessive gestational weight gain (OR 0.67, 95% CI 0.53, 0.85). CONCLUSION: This study suggests that younger maternal age and lower perceived body image are predictive of excessive gestational weight gain.