The effects of antenatal interventions on gestational weight gain in low and middle-income countries: a systematic review

Background Gestational weight gain (GWG) during pregnancy is a critical factor that affects maternal and child health outcomes. The considerable burden of inadequate GWG and the rising tide of excessive GWG are overlooked challenges in low and middle-income countries (LMICs). Methods This systematic review assessed the impact of antenatal interventions on GWG in LMICs. Randomised controlled trials (RCTs) on antenatal interventions on GWG in LMICs were included. These interventions included educational, behavioural, nutritional supplementation and pharmacological therapies. A systematic literature search was conducted using PubMed, Embase, Web of Science, CINAHL and the Cochrane Library from the start of each database through September 2025. Results Out of the 33 642 unique articles identified, 70 articles were included in our systematic review, with 59 individual RCTs and 11 cluster RCTs. Nutritional interventions (31 studies) included food and micronutrient supplementations. Micronutrient supplementation such as multiple micronutrient supplementations was found to reduce the risk of severely inadequate or inadequate GWG among pregnant women compared to iron only or iron and folic acid supplementation (Grading of Recommendations Assessment, Development and Evaluation GRADE: moderate certainty). Food supplementation showed mixed results, although most trials demonstrated higher mean GWG among undernourished pregnant women and a greater likelihood of achieving Institute of Medicine-recommended ranges (GRADE: moderate certainty). Behavioural (counselling/education) interventions (20 studies) were associated with significant reductions in excessive GWG among pregnant women with overweight or obesity and improved adequacy of GWG (GRADE: moderate certainty). Physical activity (seven studies) was found to reduce the risk of excessive GWG (GRADE: moderate certainty). Combined dietary and physical activity interventions (six studies) were found to reduce the risk of excessive GWG among pregnant women (GRADE: low certainty). Conclusions Well-structured antenatal interventions, initiated before 20 weeks of gestation and continuing beyond this period, tailored to local cultural contexts and available resources, can effectively help pregnant women in LMICs in achieving optimal GWG. PROSPERO registration number CRD42022366354.