Magnesium sulfate for neuroprotection before preterm birth: Uptake and adherence in clinical practice after National Guideline Implementation.

INTRODUCTION: Magnesium sulfate (MgSO4) administered before very preterm birth reduces the risk of cerebral palsy in surviving infants and is recommended in international guidelines. In April 2020, a national guideline for MgSO4 for fetal neuroprotection was introduced in Denmark. We evaluated clinical uptake and adherence following guideline implementation. MATERIAL AND METHODS: This retrospective medical chart review study included women who delivered at gestational age 24 + 0 to 31 + 6 weeks of gestation at nine different Danish hospitals between April 2020 and December 2023. These departments handled around 50% of all deliveries in Denmark in this period. Data were obtained from electronic medical records. The primary outcome was administration of MgSO4 for fetal neuroprotection among eligible women. Secondary outcomes included temporal trends in uptake, differences by gestational age and hospital size, and documented reasons for non-administration. Descriptive statistics were used to summarize uptake rates and patient characteristics, and comparisons were performed using appropriate statistical tests. RESULTS: A total of 583 eligible women were included. Overall, 481 women (83%) received MgSO4 for fetal neuroprotection; of these, 340 women (71%) received MgSO4 within 24 h of birth. Uptake was highest among women delivering before 28 weeks of gestation, where MgSO4 was administered in nearly all eligible cases. Among women delivering between 28 + 0 and 31 + 6 weeks, approximately one in five did not receive treatment. Uptake did not increase over the study period, suggesting early adoption followed by stable implementation. Large-volume hospitals demonstrated higher treatment rates compared with smaller hospitals. The most frequent reasons for non-administration were lack of guideline awareness/oversight at later gestational ages and rapid delivery or maternal/fetal instability at earlier gestations. CONCLUSIONS: Following the implementation of the national guideline, uptake of MgSO4 for fetal neuroprotection in Denmark was high but incomplete. Persistent gaps in treatment, particularly among women delivering after 28 weeks of gestation, indicate a need for targeted implementation strategies to improve adherence and ensure equitable neuroprotective care.