This study investigated the pattern of weight variability over 8 weeks and its associations with achieving weight gain goals and five biopsychosocial factors among pregnant women. We conducted a secondary analysis of 117 weeks of data from 16 pregnant women with a body mass index (BMI) ≥25. Weight variability was calculated from the difference of ending and beginning and maximum and minimum weights in a week and percent of each difference from baseline weight. Loess smoother, repeated measures model, and compound symmetric covariance matrix were used for analysis. The variability measure of maximum-minimum weight (overall mean: 2.1 ± 0.4 lbs.) was greater than the ending-beginning weight measure (overall mean: 0.7 ± 0.6 lbs.). Weight variability was negatively associated with achieving weight gain goals but not with biopsychosocial factors. Assessing weight variability is important during pregnancy so that preventive measures or lifestyle counseling can be instituted immediately to prevent excessive weight gain.
Keywords: clinical research areas; gestational weight gain; obesity; pregnancy; syndromes; weight management; weight variability.