PEARLS randomized lifestyle trial in pregnant Hispanic women with overweight/obesity: gestational weight gain and offspring birthweight

Background: Inappropriate gestational weight gain (GWG) has been associated with adverse perinatal events. High rates of GWG have been reported among Hispanic women. Observational studies indicate that dietary and physical activity interventions during the prenatal period may improve maternal and infant health, but very few randomized trials have been conducted among high-risk overweight/obese Hispanic women. Accordingly, we conducted a lifestyle intervention among high-risk pregnant women and evaluated its impact on achieving appropriate GWG and on improving birthweight. Methods: Eligible overweight/obese women presenting at the University Hospital in Puerto Rico with a singleton pregnancy before 16 gestational weeks were recruited and randomized to lifestyle intervention (n=15) or control group (n=16). The lifestyle intervention focused on improving physical activity and diet quality and optimizing caloric intake. We evaluated the impact of the lifestyle intervention on achieving appropriate GWG and on infant birthweight. Poisson and linear regression analyses were performed. Results: The primary intent to treat analysis showed no significant effect on achievement of appropriate GWG/week through 36 weeks in the intervention group (4/15 women) when compared with the control group (3/16 women) (adjusted incidence rate ratio = 1.14; 95% CI: 0.20, 6.67). Although not statistically significant, women in the intervention group (6/15) were 1.7 times more likely to achieve appropriate weekly GWG until delivery when compared with controls (4/16 women) (adjusted incidence rate ratio = 1.67; 95% CI: 0.40, 6.94). We observed lower adjusted birthweight-for-length z-scores in the intervention compared with the control group among male newborns with z-score difference -1.74 (-3.04, -0.43), but not among females -0.83 (-3.85, 2.19). These analyses were adjusted for age and baseline body mass index. Conclusion: Although larger studies are required to determine whether women with obesity may benefit from prenatal lifestyle interventions targeting GWG, our results are suggestive of the intervention improving adherence to established Institute of Medicine guidelines.