Trends and patterns of antiseizure medication prescribing during pregnancy between 1995 and 2018 in the United Kingdom: A cohort study

Abstract

ObjectiveTo examine antiseizure medication (ASM) prescription during pregnancy.DesignPopulation‐based drug utilisation study.SettingUK primary and secondary care data, 1995–2018, from the Clinical Practice Research Datalink GOLD version.Population or Sample752 112 completed pregnancies among women registered for a minimum of 12 months with an ‘up to standard’ general practice prior to the estimated start of pregnancy and for the duration of their pregnancy.MethodsWe described ASM prescription across the study period, overall and by ASM indication, examined patterns of prescription during pregnancy including continuous prescription and discontinuation, and used logistic regression to investigate factors associated with those ASM prescription patterns.Main Outcome MeasuresPrescription of ASMs during pregnancy and discontinuation of ASMs before and during pregnancy.ResultsASM prescription during pregnancy increased from 0.6% of pregnancies in 1995 to 1.6% in 2018, driven largely by an increase in women with indications other than epilepsy. Epilepsy was an indication for 62.5% of pregnancies with an ASM prescription and non‐epilepsy indications were present for 66.6%. Continuous prescription of ASMs during pregnancy was more common in women with epilepsy (64.3%) than in women with other indications (25.3%). Switching ASMs was infrequent (0.8% of ASM users). Factors associated with discontinuation included age ≥35, higher social deprivation, more frequent contact with the GP and being prescribed antidepressants or antipsychotics.ConclusionsASM prescription during pregnancy increased between 1995 and 2018 in the UK. Patterns of prescription around the pregnancy period vary by indication and are associated with several maternal characteristics.

Risk of Major Congenital Malformations and Exposure to Antiseizure Medication Monotherapy

“…Most importantly, we observed major changes in the pattern of ASM prescription over time, resulting in a prominent decline in the overall prevalence of MCMs. Considering that there are up to 12 million WWE of childbearing potential worldwide and that additional women are exposed to ASMs for other indications, 4 , 37 , 38 , 39 a 39% decline in the prevalence of MCMs in their offspring has major public health implications. Continued monitoring of teratogenic outcomes by registries and health databases is needed to assess the safety of prenatal exposure to newer generation ASMs.…”

“…Because most women with epilepsy (WWE) need to continue ASM treatment during pregnancy, identifying the safest treatment options for these women is essential. This information could also be applicable to women of childbearing potential who are taking ASMs for nonepilepsy conditions such as psychiatric disorders, migraine, and neuropathic pain . The assessment of pregnancy outcomes after exposure to different ASMs faces many challenges.…”

“…This information could also be applicable to women of childbearing potential who are taking ASMs for nonepilepsy conditions such as psychiatric disorders, migraine, and neuropathic pain. 3 , 4 The assessment of pregnancy outcomes after exposure to different ASMs faces many challenges. Ethical constraints preclude the conduction of randomized studies, leaving observational studies as the sole option.…”

First-trimester use of antiseizure medications and the risk of miscarriage: a population-based cohort study

“…There is now consensus that the use of certain ASMs during pregnancy leads to an increased risk of congenital malformations in offspring. 1 During pregnancy, the developing fetus is exposed to ASMs in utero through the placental transport of…”

“…Between 6 and 34 in 1000 pregnant women use ASMs during pregnancy, with the numbers rising over time. 1 2 The use of ASMs during pregnancy must balance the beneficial effects of treatment on disease management, such as preventing seizures or bipolar relapses, with the potential for teratogenic effects of in-utero drug exposure on the developing fetus. Pregnancy is a risk factor for discontinuation of ASMs, 1 3 despite discontinuation posing serious risks to both mother and child.…”