A four-armed randomised controlled demonstration trial of a multifaceted dietary intervention and probiotic capsules in obese pregnant women in the Counties Manukau Health region

This is a randomised controlled demonstration trial in 220 obese pregnant women to determine whether treatment with a probiotic capsule and/or dietary educational intervention: 1) Reduce excessive pregnancy weight gain 2) Reduce infant birthweight Participants will be randomly allocated to one of the four study groups: 1) Probiotic and dietary intervention (group 1) 2) Placebo and dietary intervention (group 2) 3) Probiotic and routine dietary advice (group 3) 4) Placebo and routine dietary advice (group 4, controls). Randomisation of participants to probiotics/placebo is double-blinded and the dietary intervention is unblinded. Probiotics: The oral probiotic capsules will contain Lactobacillus rhamnosus GG and Bifidobacterium lactis BB12 (Chr. Hansen A/S, Horsholm, Denmark) at a dose of 7*10x9 colony-forming units per day each. The probiotics capsules are taken once-daily from recruitment (between 12 weeks and zero days and 17 weeks and 6 days) until delivery. Compliance with probiotic/placebo will be assessed by counting and documenting capsule numbers remaining in canisters when repeat supplies are provided to participants at monthly intervals. Dietary intervention: Dietary education will be provided by a community health worker (CHW) trained in pregnancy nutrition, over four counselling sessions before the 26-28 week oral glucose tolerance test (OGTT). This will be complemented by 3-times weekly text messaging about healthy nutrition which will continue until birth. In-depth education will be provided by the CHW to women in the dietary intervention groups on healthy eating including: portion control, healthy food and drink choices, limiting energy dense foods, healthy recipes, label reading and managing cravings. Education on physical activity will cover four key physical activity messages (from the Te Wai o Rona program) which are relevant to pregnant women: look for ways to be active every day; increase daily exercise; move more, add more steps; and reduce sedentary leisure time. Each participant will have an initial 1 to 1.5 hour educational session (on average at about 14 weeks’ gestation) with the CHW. Three further 30 to 60 minute face-to-face sessions will occur with the CHW at two to three weekly intervals and be completed before the 26-28 week OGTT. Compliance with the dietary intervention will be assessed by the number of educational sessions participants attend with the CHW.