Body dimensions of infants exposed to antiepileptic drugs in utero: observations spanning 25 years

Prenatal exposure to antiseizure medications and fetal growth: a population-based cohort study from the Nordic countries

Background

The short- and long-term consequences of restricted fetal growth cause considerable concern, and how prenatal exposure to different antiseizure medications (ASMs) affects fetal growth remains uncertain.

Methods

This was a population-based cohort study of liveborn singleton children born in Denmark, Finland, Iceland, Norway, and Sweden from 1996 to 2017. Prenatal exposure was defined as maternal filling of prescriptions for ASM during pregnancy registered in national prescription registries and primary outcomes were adjusted odds ratios (aORs) of microcephaly or being born small for gestational age.

Findings

We identified 4,494,918 children (males: 51.3%, 2,306,991/4,494,918), including 38,714 (0.9%) children of mothers with epilepsy. In the overall population, prenatal monotherapy exposure with carbamazepine (aOR: 1.25 (95% CI: 1.12-1.40)), pregabalin (aOR: 1.16 (95% CI: 1.02-1.31)), oxcarbazepine (aOR: 1.48 (95% CI: 1.28-1.71)), clonazepam (aOR: 1.27 (95% CI: 1.10-1.48)), and topiramate (aOR: 1.48 (95% CI: 1.18-1.85)) was associated with risk of being born small for gestational age, and carbamazepine was associated with microcephaly (aOR: 1.43 (95% CI: 1.17-1.75)). In children of mothers with epilepsy, prenatal exposure to carbamazepine (aOR: 1.27 (95% CI: 1.11-1.47)), oxcarbazepine (aOR: 1.42 (95% CI: 1.18-1.70)), clonazepam (aOR: 1.40 (95% CI: 1.03-1.89)), and topiramate (aOR: 1.86 (95% CI: 1.36-2.54)) was associated with being born small for gestational age; carbamazepine, with microcephaly (aOR: 1.51 (95% CI: 1.17-1.95)). No associations with small for gestational age and microcephaly were identified after prenatal exposure to lamotrigine, valproate, gabapentin, levetiracetam, phenobarbital, acetazolamide, phenytoin, clobazam, primidone, zonisamide, vigabatrin, ethosuximide and lacosamide, but except for lamotrigine, valproate, gabapentin, and levetiracetam, numbers of exposed children were small.

Interpretation

Prenatal exposure to carbamazepine, oxcarbazepine, clonazepam, and topiramate was associated with increased risk of being born small for gestational age in both the overall population and in children of women with epilepsy suggesting that prenatal exposure to these drugs is associated with fetal growth restriction.

Funding

The NordForsk Nordic Program on Health and Welfare (83539), the Independent Research Fund Denmark (1133-00026B), the Danish Epilepsy Association, the Central Denmark Region, the Novo Nordisk Foundation (NNF16OC0019126 and NNF22OC0075033), and the Lundbeck Foundation (R400-2022-1205).

Levetiracetam Use During Pregnancy in Women With Active Epilepsy: A Hospital-Based, Retrospective Study from a Tertiary Care Hospital in North Eastern INDIA

Background and Purpose

Epilepsy during pregnancy is a therapeutic challenge. Since the 1990s, the number of licensed antiepileptic drugs has substantially increased, but safety data on managing epilepsy during conception, pregnancy, and postpartum period use of newer generation antiepileptic drugs and birth defects are limited. We analyzed efficacy and safety of levetiracetam during pregnancy in northeast Indian women with active epilepsy (WWAE) which is being presented here.

Design

Hospital based retrospective study.

Patients and Methods

A retrospective analysis was conducted based on clinical records at a tertiary care teaching hospital and referral center in Northeast India between June 2008 through June 2018 without any personal identifying information. The Obstetric data from pregnancy register was supplemented with detailed neurologic data retrieved from medical records.

Results

Of 103 women with active epilepsy, 47 (45.6%) received levetiracetam as monotherapy and 56 (54.4%) as polytherapy. During pregnancy, the seizure frequency was unchanged, or the change was better in the majority (61.1%) of the patients. With one twin pregnancy, there were 96 live births, 5 spontaneous abortions, 2 induced abortions, 1 stillbirth. However, the rate of small for gestational age was higher in WWAE, Apgar score at 5 min was lower in infants of WWAE, and the need for care in the neonatal ward and neonatal intensive care was higher. Seven of 103 exposed pregnancies had a major congenital malformation (6.79%), all 7 were exposed to other antiepileptic drugs. Generalized epilepsy accounted for 57.2%.

Conclusion

Pregnancy course is uncomplicated and neonatal outcome is good in the majority of women with active epilepsy with proper antenatal and neurologic care. Levetiracetam taken in monotherapy can be considered as safer alternative for women with epilepsy of childbearing age. Long-term follow-up of neuropsychological and cognitive development of the children of WWAE is still needed.

Relation of in-utero exposure to antiepileptic drugs to pregnancy duration and size at birth

BACKGROUND

The associations of individual antiepileptic drugs (AEDs) with pregnancy duration and size at birth, and potential dose relations, are not well characterized.

METHODS

This cohort study used nationwide Swedish register data (1996-2013). Adjusting for smoking, epilepsy and other AED indications, we used linear and quantile regression to explore associations with pregnancy duration, and birth weight, length, and head circumference (the last three operationalized as z-scores). We used logistic regression for preterm delivery, small for gestational age, and microcephaly. Lamotrigine was the reference drug.

RESULTS

6,720 infants were exposed to AEDs in utero; AED exposure increased over the study period. Relative to lamotrigine-exposed infants, carbamazepine-exposed infants were born, on average, 1.3 days earlier (mean [95% confidence interval]: -1.3 [-2.3 to -0.3]); were 0.1 standard deviations (SDs) lighter (-0.1 [-0.2 to 0.0]); and had a head circumference that was 0.2 SDs smaller (-0.2 [-0.3 to -0.1]). Pregabalin-exposed infants were born, on average, 1.1 days earlier (-1.1 [-3.0 to 0.8]); were 0.1 SDs lighter (-0.1 [-0.3 to 0.0]); and had the same head circumference as lamotrigine-exposed infants. Levetiracetam-exposed infants were born, on average, 0.5 days earlier (-0.5 [-2.6 to 1.6]); were 0.1 SDs lighter (-0.1 [-0.3 to 0.0]); and had a head circumference 0.1 SDs smaller (-0.1 [-0.3 to 0.1]). Valproic acid-exposed infants had, on average, the same duration of gestation and birth weight z-score as lamotrigine-exposed infants, but had a head circumference 0.2 SDs smaller (-0.2 [-0.2 to -0.1]). Associations between carbamazepine exposure and pregnancy duration and between valproic acid exposure and pregnancy duration and birth weight z-score were more negative at the left than at the right tails of the outcome distributions. Effect-measure modification and dose-response relations were noted for some of the associations.

CONCLUSIONS

Relative to lamotrigine, valproic acid and carbamazepine were associated with smaller head circumference.

Treatment of Peripartum Bipolar Disorder

Bipolar disorder affects women throughout their childbearing years. During the perinatal period, women with bipolar disorder are vulnerable to depressive episode recurrences and have an increased risk for postpartum psychosis. Perinatal screening is critical to identify women at risk. Although medications are the mainstay of treatment, the choice of pharmacotherapy must be made by the patient based on a risk-benefit discussion with her physician. For optimal dosing in pregnancy, therapeutic drug monitoring may be required to maintain effective drug concentrations. Residual symptoms of bipolar depression are treatable with bright light therapy as an alternative to medication augmentation.

Emilia-Romagna Study on Pregnancy and Exposure to Antiepileptic drugs (ESPEA): a population-based study on prescription patterns, pregnancy outcomes and fetal health

OBJECTIVES

To assess the prevalence of antiepileptic drug (AED) exposure in pregnant women and the comparative risk of terminations of pregnancy (TOPs), spontaneous abortions, stillbirths, major birth defects (MBDs), neonatal distress and small for gestational age (SGA) infants following intrauterine AED exposure in the Emilia Romagna region, Italy (4 459 246 inhabitants on 31 December 2011).

METHODS

We identified all deliveries and hospitalised abortions in Emilia Romagna in the period 2009-2011 from the certificate of delivery assistance registry (Certificato di Assistenza al Parto- CedAP) and the hospital discharge card registry, exposure to AEDs from the reimbursed drug prescription registries, MBDs from the regional registry of congenital malformations, and Apgar scores and cases of SGA from the CedAP. Records from different registries were linked.

RESULTS

We identified 145 243 pregnancies: 111 284 deliveries, 16 408 spontaneous abortions and 17 551 TOPs. Six hundred and eleven pregnancies (0.42%; 95% Cl 0.39 to 0.46) were exposed to AEDs. In the AED-exposed group 21% of pregnancies ended in TOPs vs 12% in the non-exposed women (OR: 2.24; 95% CI 1.41 to 3.56). Rates of spontaneous abortions, stillbirths, neonatal distress and SGA were comparable. Three hundred and fifty-three babies (0.31%; 95% CI 0.28 to 0.35) were exposed to AEDs during the first trimester. MBD rates were 2.3% in the exposed vs 2.0% in the non-exposed pregnancies (OR: 1.12, 95% CI 0.55 to 2.55).

CONCLUSION

The Emilia Romagna prevalence of AED exposure in pregnancy was 0.42%, comparable with previous European studies. Rates of spontaneous abortions, stillbirths, neonatal distress, SGA and MBDs following AED exposure were not significantly increased. The rate of TOPs was significantly higher in the AED-exposed women.

Risks and benefits of psychotropic medication in pregnancy: cohort studies based on UK electronic primary care health records

BACKGROUND

Although many women treated with psychotropic medication become pregnant, no psychotropic medication has been licensed for use in pregnancy. This leaves women and their health-care professionals in a treatment dilemma, as they need to balance the health of the woman with that of the unborn child. The aim of this project was to investigate the risks and benefits of psychotropic medication in women treated for psychosis who become pregnant.

OBJECTIVE(S)

(1) To provide a descriptive account of psychotropic medication prescribed before pregnancy, during pregnancy and up to 15 months after delivery in UK primary care from 1995 to 2012; (2) to identify risk factors predictive of discontinuation and restarting of lithium (multiple manufacturers), anticonvulsant mood stabilisers and antipsychotic medication; (3) to examine the extent to which pregnancy is a determinant for discontinuation of psychotropic medication; (4) to examine prevalence of records suggestive of adverse mental health, deterioration or relapse 18 months before and during pregnancy, and up to 15 months after delivery; and (5) to estimate absolute and relative risks of adverse maternal and child outcomes of psychotropic treatment in pregnancy.

DESIGN

Retrospective cohort studies.

SETTING

Primary care.

PARTICIPANTS

Women treated for psychosis who became pregnant, and their children.

INTERVENTIONS

Treatment with antipsychotics, lithium or anticonvulsant mood stabilisers.

MAIN OUTCOME MEASURES

Discontinuation and restarting of treatment; worsening of mental health; acute pre-eclampsia/gestational hypertension; gestational diabetes; caesarean section; perinatal death; major congenital malformations; poor birth outcome (low birthweight, preterm birth, small for gestational age, low Apgar score); transient poor birth outcomes (tremor, agitation, breathing and muscle tone problems); and neurodevelopmental and behavioural disorders.

DATA SOURCES

Clinical Practice Research Datalink database and The Health Improvement Network primary care database.

RESULTS

Prescribing of psychotropic medication was relatively constant before pregnancy, decreased sharply in early pregnancy and peaked after delivery. Antipsychotic and anticonvulsant treatment increased over the study period. The recording of markers of worsening mental health peaked after delivery. Pregnancy was a strong determinant for discontinuation of psychotropic medication. However, between 40% and 76% of women who discontinued psychotropic medication before or in early pregnancy restarted treatment by 15 months after delivery. The risk of major congenital malformations, and neurodevelopmental and behavioural outcomes in valproate (multiple manufacturers) users was twice that in users of other anticonvulsants. The risks of adverse maternal and child outcomes in women who continued antipsychotic use in pregnancy were not greater than in those who discontinued treatment before pregnancy.

LIMITATIONS

A few women would have received parts of their care outside primary care, which may not be captured in this analysis. Likewise, the analyses were based on prescribing data, which may differ from usage.

CONCLUSIONS

Psychotropic medication is prescribed before, during and after pregnancy. Many women discontinue treatment before or during early pregnancy and then restart again in late pregnancy or after delivery. Our results support previous associations between valproate and adverse child outcomes but we found no evidence of such an association for antipsychotics.

FUTURE WORK

Future research should focus on (1) curtailing the use of sodium valproate; (2) estimating the benefits of psychotropic drug use in pregnancy; and (3) investigating the risks associated with lifestyle choices that are more prevalent among women using psychotropic drugs.

FUNDING DETAILS

The National Institute for Health Research Health Technology Assessment programme.

Birth defects and epilepsy medication

Epilepsy is one of the most common neurological problems in pregnancy. Approximately one in 200 pregnancies is to a woman with epilepsy taking antiepileptic drugs. For the majority of women, pregnancy proceeds without any apparent difficulties but there is growing evidence of an increased risk of major malformations and later cognitive problems in children exposed to antiepileptic drugs in utero. This review summarizes the available evidence for these risks and examines the implications of these in the counseling and treatment of women with epilepsy.

The use of central nervous system active drugs during pregnancy

CNS-active drugs are used relatively often during pregnancy. Use during early pregnancy may increase the risk of a congenital malformation; use during the later part of pregnancy may be associated with preterm birth, intrauterine growth disturbances and neonatal morbidity. There is also a possibility that drug exposure can affect brain development with long-term neuropsychological harm as a result. This paper summarizes the literature on such drugs used during pregnancy: opioids, anticonvulsants, drugs used for Parkinson's disease, neuroleptics, sedatives and hypnotics, antidepressants, psychostimulants, and some other CNS-active drugs. In addition to an overview of the literature, data from the Swedish Medical Birth Register (1996-2011) are presented. The exposure data are either based on midwife interviews towards the end of the first trimester or on linkage with a prescribed drug register. An association between malformations and maternal use of anticonvulsants and notably valproic acid is well known from the literature and also demonstrated in the present study. Some other associations between drug exposure and outcome were found.

Impact of early life exposure to antiepileptic drugs on neurobehavioral outcomes based on laboratory animal and clinical research

Epilepsy affects approximately 1% of children under the age of 15, making it a very common neurological disorder in the pediatric population (Russ et al., 2012). In addition, ~0.4-0.8% of all pregnant women have some form of epilepsy (Hauser et al., 1996a,b; Borthen et al., 2009; Krishnamurthy, 2012). Despite the potential deleterious effects of antiepileptic drugs (AEDs) on the developing brain, their use is still required for seizure control in pregnant women (Krishnamurthy, 2012), and they represent the standard approach for treating children with epilepsy (Chu-Shore and Thiele, 2010; Quach et al., 2010; Verrotti et al., 2011). Even when AEDs are effective, there are potential side effects, including cognitive and affective changes or altered sleep and appetite. The consequences of AED exposure in development have been studied extensively (Canger et al., 1999; Modi et al., 2011a,b; Oguni, 2011). Despite intensive study, there is still debate about the long-term consequences of early life AED exposure. Here, we consider the evidence to date that AED exposure, either prenatally or in early postnatal life, has significant adverse effects on the developing brain and incorporate studies of laboratory animals as well as those of patients. We also note the areas of research where greater clarity seems critical in order to make significant advances. A greater understanding of the impact of AEDs on somatic, cognitive and behavioral development has substantial value because it has the potential to inform clinical practice and guide studies aimed at understanding the genetic and molecular bases of comorbid pathologies associated with common treatment regimens. Understanding these effects has the potential to lead to AEDs with fewer side effects. Such advances would expand treatment options, diminish the risk associated with AED exposure in susceptible populations, and improve the quality of life and health outcomes of children with epilepsy and children born to women who took AEDs during pregnancy.

Generalized tonic-clonic seizures and antiepileptic drugs during pregnancy--a matter of importance for the baby?

This study investigates the impact of generalized tonic-clonic seizures (GTCS) and antiepileptic drugs (AED) during pregnancy on gestational age (GA) and anthropometric data of newborns. One hundred twenty-nine singleton pregnancies resulting in live births from September 1999 to October 2010 in 106 women with epilepsy on AED therapy, recorded within the framework of the EURAP (International Registry of Antiepileptic Drugs and Pregnancy) program at the Department of Neurology, Medical University Innsbruck, Austria, were studied. Occurrence of ≥ 1 GTCS during pregnancy was associated with a shorter GA [median (range) 37.5 [35.1-41.6] vs. 39.7 [29.1-46.3] weeks; p ≤ 0.001], an overall five times higher preterm risk (p = 0.042) and a reduced birth weight in boys (2,900 [2,050-3,870] vs. 3,205 [1,575-4,355] g; p = 0.040). In primipara, when compared to multipara, GTCS ≥ 1 significantly reduced the GA (37.9 [35.1-41.6] vs. 39.7 [29.4-44.9] weeks; p = 0.020) and raised the incidence of low birth weight (LBW) (p = 0.022) in neonates. Antiepileptic drug polytherapy significantly increased the risk for small-for-gestational-age regarding weight (SGA(W); p = 0.035) and regarding weight and/or length (SGA(W/L); p = 0.046) when compared to monotherapy. GTCS during pregnancy was associated with diverse negative effects comprising shorter GA, an increased incidence of prematurity and LBW in primiparous women. Furthermore, AED polytherapy was correlated with an enhanced risk for SGA delivery. Re-evaluating the need for drug therapy (in particular polytherapy), maintaining seizure control for a given period before pregnancy and counseling about the importance of preventing GTCS might improve pregnancy outcome in women with epilepsy.

The clinical management of bipolar disorder complexity using a stratified model

OBJECTIVE

To provide practical and clinically meaningful treatment recommendations that amalgamate clinical and research considerations for several common, and as yet understudied, bipolar disorder complex presentations, within the framework of a proposed stratified model.

METHODS

A comprehensive search of the literature was undertaken using electronic database search engines (Medline, PubMed, Web of Science) using key words (e.g., bipolar disorder, anxiety, rapid cycling, and subsyndromal). All relevant randomised controlled trials were examined, in addition to review papers, meta-analyses, and book chapters known to the authors. The findings formed the basis of the treatment recommendations within this paper.

RESULTS

In light of the many broad presentations of bipolar disorder, a stratified model of bipolar disorder complexity was developed to facilitate consideration of the myriad of complexities that can occur during the longitudinal course of illness and the appropriate selection of treatment. Evidence-based treatment recommendations are provided for the following bipolar disorder presentations: bipolar II disorder, subsyndromal symptoms, mixed states, rapid cycling, comorbid anxiety, comorbid substance abuse, and for the following special populations: young, elderly, and bipolar disorder around the time of pregnancy and birth. In addition, some key strategies for countering treatment non-response and alternative medication recommendations are provided.

CONCLUSIONS

Treatment recommendations for the more challenging presentations of bipolar disorder have historically received less attention, despite their prevalence. This review acknowledges the weaknesses in the current evidence base on which treatment recommendations are generally formulated, and additionally emphasises the need for high-quality research in this area. The stratified model provides a means for conceptualizing the complexity of many bipolar disorder presentations and considering their management.

Antiepileptic treatment in pregnant women: morphological and behavioural effects

It is well established that children exposed to antiepileptic drugs (AEDs) in utero have an increased risk of adverse pregnancy outcomes including foetal growth retardation, major congenital malformations and impaired postnatal cognitive development. However, due to the significant maternal and foetal risks associated with uncontrolled epileptic seizures, AED treatment is generally maintained during pregnancy in the majority of women with active epilepsy. The prevalence of major malformations in children exposed to AEDs has ranged from 4 to 10%, 2-4 times higher than in the general population. More recent studies suggest a smaller increase in malformation rates. Malformation rates have consistently been higher in association with exposure to valproate than with carbamazepine and lamotrigine. Some prospective cohort studies also indicate reduced cognitive outcome in children exposed to valproate compared to carbamazepine and possibly lamotrigine. Information on pregnancy outcomes with newer generation AEDs other than lamotrigine are still insufficient.

Population-based study of antiepileptic drug exposure in utero--influence on head circumference in newborns

PURPOSE

To study the effect of AED exposure on head circumference in the newborn.

METHODS

Data on all Swedish singletons births between 1995 and 2005, over 900,000 births, were obtained from the Swedish Medical Birth Registry. The effects of AEDs on birth-weight-adjusted mean head circumference (bw-adj-HC) were estimated by comparison with data from all births in an analysis which was adjusted for year of birth, maternal age, parity, maternal smoking, and maternal body mass index.

RESULTS

A significant reduction of mean bw-adj-HC was seen after both carbamazepine (CBZ) (standard deviation scores (SDS)=0.15, p<0.001) and valproic acid (VPA) (SDS=0.10, p=0.04) in monotherapy. No effect on mean bw-adj-HC was seen for phenytoin, clonazepam, lamotrigine and gabapentin. There was a significant increase in the occurrence of microcephaly (bw-adj-HC smaller than 2 SD below the mean) after any AED polytherapy (OR=2.85, 95% CI: 1.74-4.78) but not after AED monotherapy or monotherapy with CBZ or VPA. CBZ or VPA was taken by 71% of the pregnant mothers on AED, and the usage increased over time.

CONCLUSIONS

CBZ and VPA in monotherapy during pregnancy reduce mean bw-adj-HC. AED polytherapy increases the rate of microcephaly but no significant effect is seen of AED monotherapy. The possible significance for the further development of the child is uncertain but should be explored.

Postnatal onset of severe growth retardation after in utero exposure to carbamazepine and phenobarbital: a case report

Introduction

Anticonvulsant drugs taken by pregnant women to prevent seizures are among the most common causes of potential harm to the fetus. While the immediate harmful effects manifesting as congenital abnormalities are well known, the long-term effects on growth of children exposed in utero to antiepileptic drugs are still uncertain.

Case presentation

A 7-year-old boy presented to our clinic with severe short stature. His height was 110.4 cm (−2.4 standard deviation score), with a target height of 177 cm (+0.35 standard deviation score). Height corrected for target height was −2.75 standard deviation score. He presented with mild dysmorphic facial features, hypospadias and postnatal onset of severe growth retardation. Biochemical and endocrine tests were in the normal range. The child was exposed in utero to both carbamazepine and phenobarbital.

Conclusion

This case report shows for the first time that prenatal exposure to antiepileptic drugs may induce postnatal onset of severe growth retardation, suggesting the need for growth and endocrine monitoring of offspring exposed in utero to anticonvulsant drugs.

Idiopathic megalencephaly-possible cause and treatment opportunities: from patient to lab

Megalencephaly means an increased size or weight of a generally well-formed brain. It is a feature of a heterogeneous group of mostly familial human disorders with prenatal or early childhood onset. Seizures, motor deficits, mental retardation or milder cognitive impairment are sometimes present. This review discusses idiopathic megalencephalies with regard to possible etiology and treatment opportunities. Idiopathic megalencephalies with neurological deficits as well as unilateral megalencephaly are hypothesized to be caused by disturbances of proliferation, survival or migration of neurons in the brain. The current knowledge of postnatal and adult generation of neurons and survival of adult-borne neurons is reviewed. We show an example of how a genetic potassium channel dysfunction causes not only temporal lobe epilepsy, but also postnatal progressive megalencephaly in a mouse model. We also summarize novel data on neuro-protective effects of the antiepileptic drug carbamazepine in the treatment of brain overgrowth. Findings propose that potassium ion channelopathy may underlie disease for a group of infants or young children displaying idiopathic megalencephaly and early onset epilepsy or episodic ataxia type 1. Carbamazepine's remarkable protective effects on the neuronal plasticity in the hyperexcitable state should be further studied, and maybe this drug should be considered more in treatment of temporal lobe epilepsy and megalencephaly.

Carbamazepine protects against neuronal hyperplasia and abnormal gene expression in the megencephaly mouse

Carbamazepine (CBZ) is an anticonvulsant drug used to treat epilepsy and mood disorders. However, it can cause birth defects like reduced head circumference. It was recently shown to protect against brain overgrowth and seizure-induced abnormal plasticity in the megalencephalic mice Kv1.1(mceph/mceph), (mceph/mceph) despite remaining seizures. The mceph/mceph mouse displays two-fold enlarged hippocampus due to more neurons and astrocytes. Using stereology, we found that CBZ normalized the number of neurons and astrocytes in mceph/mceph hippocampus. To characterize CBZ's protective ability on brain growth we studied the gene expression profile of mceph/mceph and wild type hippocampus, with and without CBZ treatment. Microarray analysis revealed transcripts involved in proliferation, differentiation and apoptosis including; NPY, Penk, Vgf, Mlc1, Sstr4, ApoD, Ndn, Aatk, Rgs2 and Gabra5, where Vgf may be of particular interest. The results also support CBZ's effect on synaptic transmission through GABA A receptors, which could promote apoptotic neurodegeneration, affecting cell number.

Motor and mental development of infants exposed to antiepileptic drugs in utero

We prospectively evaluated the mental (MeDQ) and motor (MoDQ) developmental quotients of 395 (67.5% of the eligible) infants of mothers with epilepsy (IME) (mean age: 15 months) enrolled in the Kerala Registry of Epilepsy and Pregnancy between 1998 and 2004. The same developmental pediatricians, blinded to antiepileptic drug (AED) exposure, evaluated the children using the Indian adaptation of the Bayley Scale of Infant Development: Their mean MeDQ was 89.1+/-29.9 and mean MoDQ was 90.7+/-26.9. The MeDQ and MoDQ were impaired (<84) for 150 (37.6%) and 133 (33.5%) IME, respectively. Maternal age, type of epilepsy, seizure frequency, or use of folic acid did not correlate with the mean MeDQ or MoDQ. Maternal education was significantly correlated with the MoDQ, but not with the MeDQ, of the infants. Infants not exposed to AEDs (n=32) had a higher MeDQ (mean: 92.3, 95% CI: 81.4-103.2) and MoDQ (mean 94.7; 95% CI 84.9-104.5) than those exposed to AEDs (MeDQ--mean: 88.6, 95% CI: 85.5-91.6; MoDQ--mean: 90.0, 95% CI: 87.3-92.8). Those exposed to polytherapy had significantly lower developmental quotients than those exposed to monotherapy. Cumulative AED scores during pregnancy had an inverse relationship with developmental quotients. On multiple regression analysis, polytherapy was a stronger predictor of lower developmental quotients than dosage. Compared with carbamazepine monotherapy, valproate monotherapy was associated with significantly lower MeDQ and MoDQ in IME (93.1 and 95 vs 86.9 and 86.1), but the differences between other AEDs were not significant for IME exposed to valproate monotherapy. A limitation of the study is that the influence of maternal intelligence on developmental quotients was not evaluated.

Phenytoin but not valproate directly affected in vitro trophoblast differentiation

OBJECTIVE

Epilepsy has been associated with poor obstetric outcomes that could be the result of the epilepsy itself or a direct effect of anti-epileptic medication on placentation. The aim of this study was to investigate any direct effect of anti-epileptic drugs on an established, in vitro bioassay of trophoblast differentiation.

STUDY DESIGN

Primary extravillous trophoblast cells were cultured in the presence of phenytoin and sodium valproate at a range of concentrations with appropriate solvent controls. The formation of multinuclear giant cells was used as a marker of trophoblast differentiation.

RESULTS

Phenytoin inhibited giant multinuclear cell formation in a dose-dependent manner; in contrast sodium valproate had no effect (p=0.011).

CONCLUSIONS

This study found that two anti-epileptic medications induced different effects on an in vitro trophoblast bioassay, suggesting that further research should be aimed at elucidating which anti-epileptic medication is most suitable for pregnant women.

Maternal epilepsy and offsprings' adult intelligence: a population-based study from Norway

PURPOSE

We examined if children of mothers with epilepsy had normal intelligence, speculating that either epilepsy or its therapy might affect this parameter.

METHODS

In a population-based cohort study in Norway, information on maternal epilepsy reported to the Medical Birth Registry of Norway, 1967-1979 was linked to information on 18-19-year-old men's intellectual ability and anthropometric measures ascertained by the Norwegian Conscripts Service, 1984-1999. The standardized intelligence test (IQ score) was reported as single-digit standard scores with values from 1 to 9. No individual information on antiepileptic drug therapy was available.

RESULTS

Mean IQ score was lower in 1,207 conscripts whose mothers had epilepsy reported on the birth notification form, as compared with 316,554 conscripts of mothers without epilepsy; 4.8 (standard deviation 1.8) versus 5.2(1.8), p < 0.001, respectively. This difference remained after adjustment for maternal education, maternal age, birth order, marital status, year of birth, and weight and length at birth. When comparing men with and without reported maternal epilepsy, the odds ratio of having an IQ score < or = 3 was 1.6 (95% confidence interval: 1.4-1.8), which was unaffected by adjustment for confounding factors. Mean height among conscripts of mothers with and without epilepsy measured 178.6 and 179.9 cm, respectively, a difference of 1.3 cm (p < 0.001).

CONCLUSIONS

We observed that almost 20 years after birth, maternal epilepsy was associated with reduced IQ score and also shorter adult height in male offspring. We do not know whether these findings will persist when epilepsy is better treated with the newer and safer generation of antiepileptic drugs.

Carbamazepine treatment recovered low N-acetylaspartate+N-acetylaspartylglutamate (tNAA) levels in the megencephaly mouse BALB/cByJ-Kv1.1(mceph/mceph)

Megencephaly mice (BALB/cByJ-Kv1.1(mceph/mceph)) display excessive brain growth and seizures related to a mutation within the potassium channel gene Kv1.1 producing a malfunctioning protein. (1)H Magnetic resonance spectroscopy (MRS) provides means to study brain transmitters and metabolites in vivo. We applied MRS to pinpoint differences in hippocampus between mceph/mceph and wild type (wt) mice. Carbamazepine (CBZ) protects against brain overgrowth in mceph/mceph. Therefore, the effects of durable oral CBZ treatment on the MR spectra were investigated. LCModel was used for spectra quantification and multivariate data analysis applied to detect group differences. mceph/mceph mice had lower levels of N-acetylaspartate+N-acetylaspartylglutamate (tNAA) and choline-containing (tCho) compounds compared to wt mice. Glutamate, glutamine, taurine and myo-inositol levels were similar in wt and mceph/mceph. Furthermore, CBZ treatment recovered tCho and tNAA levels in mceph/mceph. Thus, distinct differences in MRS spectra between mceph/mceph and wt mice were depicted and treatment effects of CBZ were monitored using MRS.

Carbamazepine protects against megencephaly and abnormal expression of BDNF and Nogo signaling components in the mceph/mceph mouse

Carbamazepine (CBZ) is a commonly used antiepileptic drug known to block voltage-gated sodium channels. Infants exposed to CBZ in utero show reduced head circumference, for reasons unknown. We investigated CBZ's effect on neural growth in megencephaly (mceph/mceph) mice lacking functional Kv1.1. Mice fed with CBZ were assessed for brain structure size, seizure behavior and expression of markers for neuronal plasticity and rescue in brain. CBZ counteracted brain overgrowth and the increased size of neurons in the mceph/mceph mouse. These effects of CBZ occurred at doses that did not fully suppress epileptic behavior. Furthermore, CBZ normalized Bdnf mRNA levels and mRNA species encoding Nogo signaling pathway proteins. In conclusion, CBZ protects efficiently against abnormal growth and abnormal expression patterns of nerve growth signaling systems in the mceph/mceph brain. These observations and the effect of CBZ in utero suggest that CBZ treatment might be advantageous in some types of human idiopathic megalencephaly.

Community-based, prospective, controlled study of obstetric and neonatal outcome of 179 pregnancies in women with epilepsy

PURPOSE

This study evaluated obstetric and neonatal outcome in a community-based cohort of women with active epilepsy (WWAE) compared with the general pregnant population receiving modern obstetric care.

METHODS

We reviewed the total population who gave birth between January 1989 and October 2000 at Kuopio University Hospital. Obstetric, demographic, and epilepsy data were collected prospectively from 179 singleton pregnancies of women with epilepsy and from 24,778 singleton pregnancies of unaffected controls. The obstetric data from the pregnancy register was supplemented with detailed neurologic data retrieved from the medical records. The data retrieved were comprehensive because of a follow-up strategy according to a predecided protocol.

RESULTS

During pregnancy, the seizure frequency was unchanged, or the change was for the better in the majority (83%) of the patients. We found no significant differences between WWAE and controls in the incidence of preeclampsia, preterm labor, or in the rates of caesarean sections, perinatal mortality, or low birth weight. However, the rate of small-for-gestational-age infants was significantly higher, and the head circumference was significantly smaller in WWAE. Apgar score at 1 min was lower in children of WWAE, and the need for care in the neonatal ward and neonatal intensive care were increased as compared with controls. The frequency of major malformations was 4.8% (-0.6-10.2%; 95% confidence interval) in the 127 children of WWAE.

CONCLUSIONS

Pregnancy course is uncomplicated and neonatal outcome is good in the majority of cases when a predecided protocol is used for the follow-up of WWAE in antenatal and neurologic care. Long-term follow-up of the neurologic and cognitive development of the children of WWAE is still needed.

Pregnancy in women who have epilepsy

Ideal, comprehensive care of women who have epilepsy during the reproductive years must include effective preconceptional counseling and preparation. The importance of planned pregnancies with effective birth control should be emphasized, with consideration of the effects of the enzyme-inducing AEDs on lowering efficacy of hormonal contraceptive medications and the need for back-up barrier methods. Before pregnancy occurs, the patient's diagnosis and treatment regimen should be reassessed. Once the diagnosis of epilepsy is confirmed, it is important to verify if the individual patient continues to need medications and if she is taking the most appropriate AED to balance control of her seizures with teratogenic risks. For most women who have epilepsy, withdrawal of all AEDs before pregnancy is not a realistic option. A decision to undergo a trial while not taking AEDs before a planned pregnancy should be based on the same principles used for AED withdrawal in any person who has epilepsy. The taper should be completed at least 6 months before planned conception to provide some reassurance that seizures are not going to recur. If a woman who has epilepsy is in the more prevalent category of needing AEDs for seizure control, then monotherapy at the lowest effective dosage should be used. If large daily doses are needed, then frequent smaller doses or extended-release formulations may be helpful to avoid high peak levels. Some of the newest information about differential risks between AEDs also should be considered. The woman's AED regimen should be optimized and folate supplementation should begin before pregnancy. Given that 50% of pregnancies are unplanned in the United States, folate supplementation should be encouraged in all women of childbearing age who are taking any AED for any indication. Dosing recommendations vary from 0.4 mg/d to 5 mg/d. It is not uncommon for a physician to consider changing AED regimens when the patient first reports that she is pregnant. In many cases, she already is in or past the critical period of organogenesis (Table 3). If a woman who has epilepsy presents after conception and is taking a single AED that is effective, her medication usually should not be changed. Exposing the fetus to a second agent during a crossover period of AEDs only increases the teratogenic risk, and seizures are more likely to occur with any abrupt medication changes. If a woman is on polytherapy, it may be possible to switch to monotherapy safely. Seizure control remains an important goal during pregnancy. In particular, convulsive seizures place the mother and fetus at risk. Nonconvulsive seizures also may be harmful, especially if they involve falling or other forms of trauma. Monitoring serum AED levels during pregnancy can be helpful in optimizing seizure control. Prenatal screening can detect major malformations in the first and second trimesters. Vitamin K1 is given 10 mg/d orally during the last month of pregnancy followed by 1 mg intramuscularly or intravenously to the new-born. Although women who have epilepsy and women who are taking AEDs for other indications do have increased risks for maternal and fetal complications, these risks can be reduced considerably with effective preconceptional planning and careful management during pregnancy and the postpartum period.

Statistics on Deliveries of Mothers with Epilepsy at Yokohama City University Hospital

PURPOSE

To survey and summarize the treatment of pregnant women with epilepsy and to obtain data for the improvement of daily treatment regimens.

METHODS

We reviewed medical records of 36 deliveries of 25 mothers with epilepsy at Yokohama City University Hospital from September 1991 to December 2000 and statistically compared the differences in drug-taking profiles, complications during pregnancy, types of delivery, and complications at delivery between the epilepsy group and a control group (656 total deliveries after 22 weeks except for epilepsy cases in 1991 and 1992 at Yokohama City University Hospital).

RESULTS

Of the 25 mothers with epilepsy, three with idiopathic generalized epilepsy, 12 were symptomatic for partial epilepsy. Their mean age at delivery was 29.0 years. The mean age at onset of epilepsy was 13.9 years. Of the 36 pregnancies, 30 (83.3%) cases continued antiepileptic drug (AED) taking throughout the pregnancies; 23 (63.9%) cases received monotherapy. Phenobarbital was the most frequently used drug in monotherapies. Seven (19.4%) cases received polytherapy. Seven (19.4%) patients experienced epileptic seizures during pregnancy. One case showed a low serum AED level. No statistically significant difference was found in complications during pregnancy, types of delivery, or complications at delivery, excluding abnormal rotation in the birth canal. Congenital malformation (cleft lip with palate) was observed in one (2.9%) case. The mother was 39 years old at delivery and had myoma uteri. Onset of epilepsy was at 14 years. She had been taking three kinds of AEDs: 1,400 mg/day of sodium valproate (VPA), 1.5 mg/day of clonazepam (CZP), and 200 mg/day of zonisamide (ZNS). Serum concentrations at pregnancy week 10 were 85.3 microg/ml VPA, 18.1 microg/L CZP, and 10.5 microg/ml ZNS. She also had been taking folic acid, 5 mg/day, but the serum concentration was not measured.

CONCLUSIONS

The method of treatment and the management of pregnancy were left to the discretion of each doctor. However, in most cases, monotherapy was selected; and the frequency of complications was not significantly different from that of the control group, excluding the frequency of abnormal rotation in the birth canal. However, we could have been more proactive in calculating the risks of pregnancy for women with epilepsy and adjusted treatment in anticipation of a planned pregnancy, before the patient actually became pregnant. Additionally, a closer working relationship between the obstetrician and the physician who treats the epilepsy would seem to be a further requirement for the patient's well-being, as well as her child's, during pregnancy.

Drugs that affect the fetus and newborn infant via the placenta or breast milk

In general, drugs that are taken by a mother during pregnancy or after birth may be transferred to the fetus or the infant (through breast milk). Many factors are involved that determine the amount of drugs that are transferred and their potential effects on the fetus or infant. A careful assessment of the risk versus benefit is necessary and should be individualized. In the breastfed infant, many measures can be undertaken further so that the amount of drug transferred to the infant is minimized.

The Australian registry of anti-epileptic drugs in pregnancy: experience after 30 months

BACKGROUND

Most women with epilepsy need to take antiepileptic drugs (AEDs) in pregnancy to prevent the potentially harmful effects of seizures. Retrospective studies have demonstrated an increased chance of having a child with a birth defect (BD) in women with epilepsy taking AEDs. It is uncertain how much of this risk is directly caused by the AEDs and whether certain drugs or combinations are associated with a greater risk.

AIMS

To establish a register to evaluate prospectively the incidence of adverse pregnancy outcomes in women exposed to specific AEDs; to determine whether certain AEDs or combinations were associated with a greater risk; and to determine whether other factors influenced the risk.

METHODS

An Australia-wide, prospective, voluntary, telephone-interview based, observational register. Three groups of pregnant women were enrolled: those with epilepsy taking AEDs, those with epilepsy not taking AEDs, and those taking AEDs for a non-epileptic indication. The pregnancy outcomes were evaluated by follow-up interviews and by reference to hospital and treating doctors' records.

RESULTS

Over the first 30 months of the study (till December 2001) 334 eligible women were enrolled, with all states and territories being represented. Two hundred and ninety two pregnancies had been completed, of which 256 (88%) resulted in a healthy live birth, 19 (6.5%) a live birth with a birth defect, four an induced abortion because of a detected malformation on ultrasound, one premature labour with a stillbirth and 12 (4%) spontaneous abortions. Of the completed pregnancies, 269 were exposed to at least one AED during the first trimester. The incidence of birth defects in relation to specific AEDs was: valproate (16.7%), phenytoin (10.5%), lamotrigine (7.7%) and carbamazepine (3.3%), none of which was significantly different from that in women with epilepsy not taking an AED (4.3%, n.s.). The dose of valproate taken was higher in pregnancies with BD compared to those without (mean 2081 mg vs. 1149 mg, p<0.0001). The incidence of folate supplementation being taken prior to conception did not differ for pregnancy outcomes with or without BD (70% vs. 66%, n.s.).

CONCLUSIONS

The model for the Australian Pregnancy Register appears to be successful, with strong enrolment from all regions over the first 30 months. The study is prospective and includes reference to all new AEDs approved in Australia over the past decade. Analysis of the pregnancy outcomes to date may reveal early trends, but numbers are still to small for any definitive conclusions to be made regarding the relative risk in pregnancy of individual AEDs.

Epilepsy and pregnancy: Report of an Epilepsy Research Foundation Workshop

Pregnancy in women with epilepsy (WWE) is known to be associated with a higher risk of congenital malformations than is associated with pregnancy in non-epileptic women. Several factors have been identified to account for the increased risk, including the direct teratogenic effects of antiepileptic drug (AED) therapy, indirect effects of these drugs by interfering with folate metabolism, genetic abnormalities in drug or folate metabolism, and possibly an arrhythmogenic effect of maternal drug therapy on the embryonic heart, leading to ischaemia in developing tissues. A harmful effect of maternal seizures on the developing embryo has not been proven, although seizures and status epilepticus account for most of the excess maternal mortality in women with epilepsy. Abrupt withdrawal of drug therapy by the mother may be an important contributory factor. Less is known about the psychomotor development of children born to mothers with epilepsy because few studies have been designed to follow their progress throughout childhood. Retrospective studies suggest that impaired cognitive development may be associated with maternal drug therapy, particularly valproate. There is an urgent need to evaluate these risks and, with this in mind, several prospective registers have been set up to collect data from pregnancies in women with epilepsy.

The teratogenic effect of carbamazepine: a meta-analysis of 1255 exposures

Maternal use of antiepileptic drugs during pregnancy has been associated with an increased risk of major congenital abnormalities in the fetus. Carbamazepine (CBZ) is an antiepileptic drug that was developed and marketed mainly for the treatment of epileptic seizures. Some investigators described an increased rate of major congenital anomalies following treatment with CBZ during pregnancy while others found no such increase. In order to quantify better the risks of exposure to CBZ during pregnancy, we pooled data from prospective studies known to us. We found in prospective studies involving 1255 cases of exposure that CBZ therapy increased the rate of congenital anomalies, mainly neural tube defects, cardiovascular and urinary tract anomalies, and cleft palate. CBZ may also induce a pattern of minor congenital anomalies and developmental retardation, but our study did not address these endpoints. CBZ also appears to reduce gestational age at delivery. A combination of CBZ with other antiepileptic drugs is more teratogenic than CBZ monotherapy. Children born to untreated epileptic women do not appear to have an increased rate of major birth defects. In light of these results, we recommend performing a level 2 ultrasound and fetal echocardiography in women treated with CBZ during pregnancy.

Maternal antiepileptic drug use and effects on fetal development

Many pregnant women take antiepileptic medications, and concern has arisen about the risks this poses to the fetus. It has been debated whether the causative agent is the medication or the underlying maternal disorder. Review of the recent literature indicates that the effects seem to be from the medications themselves. The frequency of malformations is about two to three-fold above the background rate and is dose-related for some of the medications. There seem to be effects on birth weight, length, and head circumference caused by at least some of the medications. The risks are greater when more than one medication is used. Cognitive effects from the medications have been shown, although these effects are of lower magnitude than previously reported. More investigation needs to be done to determine the exact risks of each individual medication, especially the newer ones. Studies on underlying mechanisms indicate potential genetic susceptibility and altered developmental gene expression patterns.

Teratogenesis with antiepileptic drugs: practical management of young women with epilepsy

Children born to mothers who take antiepileptic drugs during pregnancy have a 2-4 fold increased risk for birth defects and also a risk of growth retardation and possibly impaired psychomotor development. Despite their teratogenic effects, antiepileptic drugs are used during pregnancy because uncontrolled epileptic seizures are considered more hazardous to the fetus than the drug therapy. The aim is to maintain seizure control with the appropriate drug given in monotherapy at the lowest effective dosage. These issues have implications for the management of young women with epilepsy in general, since major changes in drug therapy and other attempts to reduce the teratogenic risks should be accomplished before conception in order to be effective and safe.