BACKGROUND: Gestational weight gain (GWG) below or above the Institute of Medicine (IOM) recommendations has been associated with adverse perinatal outcomes. Few studies have examined the effect of prenatal nutrient supplementations on GWG in low- and middle-income countries (LMICs). OBJECTIVES: To investigate the effects of multiple micronutrient supplements (MMS) and small-quantity lipid-based nutrient supplements (LNS) on GWG in LMICs. METHODS: A two-stage meta-analysis of individual participant data was conducted to examine the effects of MMS (45,507 women from 14 trials) and small-quantity LNS (6,237 women from 4 trials) on GWG compared to iron and folic acid supplements only. Percent adequacy of GWG and total weight gain at delivery were calculated according to the IOM 2009 guidelines. Binary outcomes included severely inadequate (% adequacy 125%) GWG. Results from individual trials were pooled using fixed-effects inverse-variance models. Heterogeneity was examined using I2, stratified analysis, and meta-regression. RESULTS: MMS resulted in a greater % adequacy of GWG (weighted mean difference (WMD): 0.86%; 95% CI: 0.28%,1.44%; P