Valproate-containing medicines (VPA) are first-line treatment for epilepsy; however, they pose teratogenic risks, restricting their use in women of childbearing age. We aimed to estimate the secular trends in use of VPA and alternative treatments in young women, and to characterise dose/strength, treatment duration and indication in new VPA users We conducted a population-based cohort study using primary care records from the Netherlands, Spain and the UK, primary and outpatient specialist care records from Germany and Belgium (and hospital records from Finland, all mapped to the OMOP Common data model. All women present in the databases aged ≥12 years and ≤55 years on 1st of January of each year in the period 2010-2022 (or latest available), with at least 365 days of prior observation were included. Incidence and prevalence of VPA use in young women decreased between 2010 and 2021, while prevalence of the alternative treatments pregabalin and gabapentin increased, especially in CPRD (it rises from 0.5% to 1.5%). Median age of new VPA users ranged between 40-43 years. Anxiety and depressive disorder were frequent comorbidities, and use of hormonal contraceptives low. Average treatment duration varied substantially across databases . Incidence and prevalence of use of VPA among young women declined since 2015. Conversely, alternative antiepileptics have increased in uptake, particularly gabapentinoids. The use of standardized federated analytics allowed for a rapid assessment of VPA utilisation, supporting the regulatory agencies in their decision making and improving patient safety across Europe.