Ripple effect of lifestyle interventions during pregnancy on untreated partners’ weight

OBJECTIVE: Weight loss interventions have a positive “ripple effect” on untreated partners weight, but ripple effects in pregnancy are unknown. The objective of this study is to determine whether prenatal lifestyle interventions that reduced gestational weight gain in pregnant women had a positive “ripple” effect on untreated partner weight. METHODS: Two clinical trials with the same outcome measures randomized pregnant women to lifestyle intervention or usual care. Untreated partners were randomized according to their pregnant partner’s group allocation and assessed at study-entry (~13 weeks’ gestation), 35 weeks’ gestation, 6 and 12 months postpartum. RESULTS: 122 partners (100% male, 23% Hispanic, 82% married, 48% obese) were randomized to intervention (N=59) or usual care (N=63). There was no intervention or intervention by time interaction effect on partner weight (P = 0.795). Partner weight changes were not statistically significant (P = 0.120) from study-entry to 35 weeks’ gestation (Mean 0.19 kg; 95% CI −0.73 to 1.24) or to 12 months postpartum (Mean 0.82 kg; 95% CI: −0.26 to 1.91 kg). CONCLUSIONS: There was no evidence of a ripple effect on partner weight. In a self-selected sample, partners of pregnant women appear not to experience sympathy weight gain.