Antenatal magnesium sulphate for preterm foetal neuroprotection in low- and middle-income countries: a scoping review of research studies and guidelines.

Background: Antenatal magnesium sulphate reduces the risk of cerebral palsy (CP) for infants born very preterm. While endorsed by the World Health Organization for global implementation in 2015, studies underpinning this recommendation were conducted in high-income countries. Our objective was to systematically gather, organise, and map published research studies on the use of antenatal magnesium sulphate for preterm foetal neuroprotection in low- and middle-income countries (LMICs), and to obtain existing relevant national and international clinical practice guidelines from (or for) LMICs. Methods: Following scoping review methods, we searched nine databases and the websites of societies/ministries of health for relevant qualitative or quantitative studies and national or international guidelines, published from 2015, from any LMIC. We screened each publication for inclusion, and two reviewers independently extracted information. Content analysis included narrative summaries and descriptive statistics. Results: In total, 57 research studies (12 randomised controlled trials) and 25 clinical guidelines were included in the analysis. Most (n = 75) were in English, from lower-middle (n = 45) and upper-middle (n = 31) countries, and published between 2020 and 2025 (n = 60). The most common research scope was effects and/or safety (n = 38). The remaining studies focused on intervention uptake or quality improvement programmes (n = 10), mechanisms of action (n = 5), or regimen comparisons (n = 4). Short-term outcomes were common, and CP was described in only four studies. Regarding clinical guidelines, magnesium sulphate was usually included in general guidelines (n = 24), those published by professional associations (n = 18), or those published by government bodies (n = 6). After categorisation, an upper gestational limit of 32 weeks was most common (n = 18). Treatment regimens varied, commonly including a 4 g intravenous loading dose (n = 12) and a 1 g/h intravenous maintenance dose (n = 11). One in three recommended no specific regimen. Conclusions: A sizeable number of heterogeneous studies and clinical guidelines exist, primarily from middle-income countries, regarding magnesium sulphate for neuroprotection. Further context-specific research may include regimen comparisons, impact, and implementation studies, informing future updates to clinical guidelines globally. Registration: OSF 10.17605/OSF.IO/ASN67.