LAUSR

Objectives Gestational weight gain (GWG) may reflect dynamic changes to prenatal diet quality, however, this relationship has been understudied. This study explored the relationship between GWG, pre-pregnancy BMI, and prenatal diet quality. Methods A secondary analysis examined a subset of 1268 women in the longitudinal Infant Feeding Practices Study (IFPS II) with 3rd trimester Diet History Questionnaire data. Diet quality was assessed with the Alternative Health Eating Index for Pregnancy (AHEI-P). Self-reported pre-pregnancy BMI, and total GWG (72% response rate) were used to classify GWG as inadequate (I), adequate (A), and excessive (E) according to the Institute of Medicine's recommendations. Tukey-adjusted generalized linear models, adjusting for sociodemographic factors, Women, Infants, and Children participation, parity, and energy intake, compared GWG groups on mean AHEI-P scores. The interaction between pre-pregnancy BMI and GWG group was tested and if significant, models were stratified by BMI group. Sensitivity analyses using multiply imputed GWG data were conducted. Results On average, AHEI-P scores were 61.3 (of 130), women were 28.9 years, higher socioeconomic status (40% college graduates) and mostly non-Hispanic White (84%). Pre-pregnancy BMI and GWG were inversely associated with AHEI-P scores (P < 0.0001). The association between GWG and diet quality was modified by BMI group (P = 0.04). In stratified adjusted analyses, GWG was associated with AHEI-P scores (P < 0.05) among women with pre-pregnancy underweight (I = 54.4 ± 3.9, A = 59.7 ± 3.6, E = 63.5 ± 3.5), normal weight (I = 59.2 ± 1.5, A = 61.0 ± 1.2, E = 59.3 ± 1.2), overweight (I = 62.3 ± 2.9, A = 60.7 ± 1.6, E = 59.4 ± 1.5), and obesity (I = 59.2 ± 1.8, A = 57.8 ± 2.0, E = 60.6 ± 1.5). However, no significant post-hoc differences between GWG groups were observed among any of the pre-pregnancy BMI groups. Findings from the multiple imputation analysis did not differ from complete case analysis findings. Conclusions GWG and prenatal diet quality differed according to pre-pregnancy BMI in this study. Adherence to GWG recommendations during pregnancy is an important predictor of maternal diet quality and should be examined in conjunction with pre-pregnancy BMI. Funding Sources There are no funding sources to disclose.