Myo-Inositol, Probiotics, and Micronutrient Supplementation From Preconception for Glycemia in Pregnancy: NiPPeR International Multicenter Double-Blind Randomized Controlled Trial

<b>Objective:</b> Better preconception metabolic and nutritional health are hypothesized to promote gestational normoglycemia and reduce preterm birth, but evidence supporting improved outcomes with nutritional supplementation starting preconception is limited. <p><b>Research Design and Methods:</b> Double-blind randomized controlled trial recruited from the community 1729 UK, Singapore and New Zealand women aged 18-38 years planning conception. We investigated if a nutritional formulation containing myo-inositol, probiotics and multiple micronutrients (intervention), compared with a standard micronutrient supplement (control), taken preconception and throughout pregnancy, could improve pregnancy outcomes. The primary outcome was combined fasting, 1-hour and 2-hour post-load glycemia (28 weeks’ gestation oral glucose tolerance test).</p> <p><b>Results</b>: Between 2015-2017, participants were randomized to control (n=859) or intervention (n=870); 585 conceived within 1-year and completed the primary outcome (295 intervention, 290 control). In an intention-to-treat analysis adjusting for site, ethnicity and preconception glycemia with pre-specified p<0.017 for multiplicity, there were no differences in gestational fasting, 1-hour and 2-hour glycemia between groups (β [95%CI] log_e mmol/L intervention versus control: -0·004 [-0·018, 0·011], 0·025 [-0·014, 0·064], 0·040 [0·004, 0·077], respectively). Between the intervention and control groups there were no significant differences in gestational diabetes (24·8% versus 22·6%, adjusted risk ratio aRR=1·22 [0·92, 1·62]), birthweight (adjusted β=0·05kg [-0·03, 0·13]), or gestational age at birth (mean 39.3 versus 39.2 weeks, adjusted β=0·20 [-0·06, 0·46]), but there were fewer preterm births (5·8% versus 9·2%, aRR=0·43 [0·22, 0·82]) adjusting for pre-specified covariates.</p> <p><b>Conclusions: </b>Supplementation with myo-inositol, probiotics and micronutrients preconception and in pregnancy did not lower gestational glycemia, but did reduce preterm birth. </p> <br>