Valproate Prescribing for Female Adolescents and Management of the Associated Teratogenicity Risk, Royal Children's...

To assess the frequency of valproate prescribing for female patients of childbearing age at the Royal Children's Hospital, Melbourne, and to assess the frequency of documented discussions with these patients about the teratogenicity of valproate and the discussions or prescribing of contraception.

Retrospective audit of hospital electronic medical records data; analysis of Pharmaceutical Benefits Scheme (PBS) valproate dispensing data.

13- to 18-year-old girls or women prescribed valproate at the Royal Children's Hospital, Melbourne during 29 May 2022-29 May 2024; PBS valproate dispensing data for Australia for the 2023 calendar year.

Characteristics of adolescent female patients prescribed valproate; documented discussions of valproate-related teratogenicity, and discussions or prescribing of contraception; population valproate prescribing rates for Australia and by state.

Valproate was prescribed for 245 female patients aged 13-18 years during 2022-2024 (median age, 16 years; interquartile range [IQR], 14-17 years); the median prescribed daily dose was 600 mg (IQR, 400-800 mg; range, 200-2000 mg). Valproate was prescribed for treating epilepsy for 221 patients (90%), including 97 (44%) with drug-resistant epilepsy; 160 patients (65%) had neurodevelopmental disabilities. Teratogenicity was discussed with 32 patients (13%), less frequently with patients with a neurodevelopmental disability (9% vs. 20%; odds ratio [OR], 0.41; 95% confidence interval [95% CI], 0.19-0.88). Contraception was discussed with 69 patients (28%); the proportion was larger for patients with neurodevelopmental disabilities (34% vs. 16%; OR, 2.66; 95% CI, 1.37-5.14). Contraception was prescribed for 50 patients (20%); the proportion was larger for patients with neurodevelopmental disabilities (25% vs. 12%; OR, 2.50; 95% CI, 1.18-5.30). The national PBS-subsidised dispensing rate during 2023 was 621 per 100,000 girls and women aged 13-18 years; in Victoria it was 556 per 100,000 girls and women aged 13-18 years.

Despite the risk of teratogenicity, valproate was prescribed for a considerable number of female adolescents at the Royal Children's Hospital during 2022-2024 and across Australia during 2023. Its teratogenicity was discussed with few patients, nor were discussions or prescribing contraception frequent. Contraception was more frequently discussed and prescribed for patients with neurodevelopmental disability, but teratogenicity was discussed less often.