Analysis of Evidence
Does preconceptional folic acid supplementation reduce the risk of birth defects in neonates of WWE taking AEDs?
To be included in the analysis, articles had to measure the association between preconceptional folic acid use and the outcome of major congenital malformations (MCMs). MCMs were defined as structural abnormalities with surgical, medical, or cosmetic importance (Holmes et al., 2001). The development of an MCM was considered an objective outcome.
Eleven articles relevant to this question were identified by the literature search. The articles were rated according to the American Academy of Neurology (AAN) classification of therapeutic evidence scheme (see Appendix e-4a). Six studies were graded Class IV and will not be discussed further. The remaining studies were rated Class III (see Table e-1).
Among the five Class III articles, one study (n = 156) showed an increased risk of MCMs with lack of folic acid supplementation [odds ratio (OR) 16.88, 95% confidence interval (CI) 4.79–59.52] (Betts & Fox, 1999). The folic acid supplementation dose in this study was reported as 2.5–5 mg per day. A second Class III study measured a significant association between serum folic acid concentrations <4.4 nmol/L and neonatal malformation (adjusted OR 5.8, 95% CI 1.3–27, p = 0.02) (Kaaja et al., 2003).
Several Class III studies failed to show an association between folic acid and MCMs but were insufficiently sensitive to exclude a substantial risk reduction from folic acid supplementation. One study reported an OR of 1.67 for MCMs in the offspring of mothers on valproate who were not taking folic acid supplementation. However, the result was not significant (95% CI 0.62–4.50) (Vajda et al., 2003). Another study showed no effect of folic acid supplementation (OR 0.86, 95% CI 0.34–2.15) (Vajda et al., 2004), but lacked the statistical precision to exclude a potential benefit. The final study (Wyszynski et al., 2005) was inconclusive, since all WWE who had offspring with MCMs had folic acid supplementation.
The risk of MCMs in the offspring of WWE is possibly decreased by folic acid supplementation (two adequately sensitive Class III studies).
Preconceptional folic acid supplementation in WWE may be considered to reduce the risk of MCMs (Level C).
Folic acid supplementation is generally recommended to reduce the risk of MCMs during pregnancy (Czeizel et al., 2004), and although the data are insufficient to show that it is effective in WWE, there is no evidence of harm and no reason to suspect that it would not be effective in this group. Therefore, the strength of this evidence should not impact the current folic acid supplementation recommendation that all women of childbearing potential, with or without epilepsy, be supplemented with at least 0.4 mg of folic acid daily prior to conception and during pregnancy (Morbidity and Mortality Weekly Report, 1992). There was insufficient published information to address the dosing of folic acid and whether higher doses offer greater protective benefit to WWE taking AEDs.
What is the risk of hemorrhagic disease in neonates born to WWE taking AEDs?
To be included in the analysis, studies had to compare the risk of neonatal hemorrhagic complications in newborns of WWE taking AEDs to newborns of women without epilepsy. Hemorrhagic complications were defined as any hemorrhage within 24 h of birth. Studies looking solely at surrogate markers of bleeding risk such as coagulation factor levels were excluded. The risk of bias in each study was measured using the AAN prognostic classification of evidence scheme (see Appendix e-4b).
Ten articles were identified by the literature search. All but two articles were rated Class IV. The remaining two articles, one Class II and one Class III, are summarized in Table e-2.
The Class II article (Kaaja et al., 2002) evaluated large numbers of newborns born to mothers taking enzyme-inducing AEDs compared to healthy controls. Upon evaluation of multiple risk factors for neonatal hemorrhage using logistic regression analysis, enzyme-inducing AEDs did not emerge as significantly associated with neonatal hemorrhage (OR 1.1, 95% CI 0.3–4.6, p = 0.8). However, the high upper limit of the 95% CI indicates that the possibility of a substantial risk cannot be excluded. The majority of hemorrhages in AED-exposed newborns were accounted for by premature birth (<34 weeks). The Class III article (Choulika et al., 2004) also showed no increased risk with AEDs, which were mostly enzyme-inducers [relative risk (RR) 0.51, 95% CI 0.21–1.24, p = 0.14]. All newborns in both of these studies received vitamin K 1 mg, i.m., at birth, but the mothers received no prenatal vitamin K supplementation.
There is insufficient evidence to determine if the risk of neonatal hemorrhagic complications in the newborns of WWE taking AEDs is substantially increased (one inadequately sensitive Class II study).
Counseling of WWE who are pregnant or are contemplating pregnancy should reflect that there is insufficient evidence to support or refute an increased risk of hemorrhagic complications in the newborns of WWE taking AEDs (Level U).
Does prenatal vitamin K supplementation reduce the risk of hemorrhagic complications in the newborns of WWE taking AEDs?
No articles were found that provided higher than Class IV evidence.
Evidence is inadequate to determine if prenatal vitamin K supplementation in WWE reduces neonatal hemorrhagic complications.
There is insufficient evidence to support or refute a benefit of prenatal vitamin K supplementation for reducing the risk of hemorrhagic complications in the newborns of WWE (Level U).
Newborns exposed to enzyme-inducing AEDs in utero routinely receive vitamin K at delivery, as is the routine practice for all newborns (American Academy of Pediatrics Vitamin K Ad Hoc Task Force, 1993).
Do maternally ingested AEDs cross the placenta? Do maternally ingested AEDs penetrate into breast milk?
Articles were included if the investigators measured AED levels in at least five mother–child pairs for evaluation of placental transfer and a minimum of five maternal serum–breast milk pairs. Each study’s risk of bias was rated using the AAN prognostic classification of evidence scheme. The AED level in the mother’s serum was the risk factor; the AED level in the neonate’s serum was the outcome for the first question, and the AED level in the breast milk was the outcome for the second question. Studies were downgraded because of inadequately described serum AED concentrations; nongeneralizable population; samples not obtained at uniform times, such as the maternal sample and the cord or milk sample obtained at differing times in the same pair; or fewer than 80% of samples collected according to protocol.
There is no threshold level of passive exposure to AEDs that is established to impart a clinically important risk to the fetus or neonate. For the purpose of this parameter, the panel stipulated that an AED transfer rate of 0.6 (neonatal-to-maternal plasma concentration ratio or a milk-to-maternal concentration ratio) was potentially clinically important. Similarly, the panel stipulated that any trend of increasing plasma concentrations in the neonate by 25% over the evaluated period (generally 3 days up to 1 month) was clinically important. The literature search identified 19 articles. Two articles were Class I, 16 were Class II, and one was Class III (see Table e-3).
One Class I study (Kuhnz et al., 1988) and one Class II study (Nau et al., 1980) provided evidence that primidone and phenobarbital significantly cross the placenta (cord-to-maternal concentration >0.6).
One Class I study (Nau et al., 1981) and two Class II studies (Ishizaki et al., 1981; Takeda et al., 1992) provided evidence that valproate significantly crosses the placenta.
At least two Class II studies per AED (Ishizaki et al., 1981; Yerby et al., 1990; Takeda et al., 1992; Gomita et al., 1995; Johannessen et al., 2005; Tomson et al., 2007) provided evidence that the following AEDs significantly cross the placenta: phenytoin, carbamazepine, and levetiracetam.
One Class II study for each of the following AEDs showed significant placental crossing: gabapentin (Ohman et al., 2005), lamotrigine (Ohman et al., 2000), oxcarbazepine (Myllynen et al., 2001), and topiramate (Ohman et al., 2002).
One Class III study showed significant placental crossing for ethosuximide (Kuhnz et al., 1984).
Phenobarbital, primidone, phenytoin, carbamazepine, levetiracetam, and valproate probably cross the placenta in potentially clinically important amounts (one Class I and supporting Class II studies or two or more Class II studies).
Gabapentin, lamotrigine, oxcarbazepine, and topiramate possibly cross the placenta in potentially clinically important amounts (at least one Class II study for each).
There are insufficient data to determine if ethosuximide crosses the placenta in clinically important amounts (one Class III study showing significant penetration).
The fact that phenobarbital, primidone, phenytoin, carbamazepine, levetiracetam, valproate, gabapentin, lamotrigine, oxcarbazepine, and topiramate cross the placenta may be factored into the clinical decision regarding the necessity of AED treatment for a woman with epilepsy (Level B for phenobarbital, primidone, phenytoin, carbamazepine, levetiracetam, and valproate; and Level C for gabapentin, lamotrigine, oxcarbazepine, and topiramate).
One Class I study (Kuhnz et al., 1988) and one Class II study (Nau et al., 1980) for primidone demonstrated significant penetration into breast milk.
Two Class II studies for levetiracetam (Tomson et al., 2007; Johannessen et al., 2005) demonstrated significant penetration into breast milk.
One Class II study for each of the following AEDs showed significant breast-milk penetration: gabapentin (Ohman et al., 2005), lamotrigine (Ohman et al., 2000), and topiramate (Ohman et al., 2002).
One Class III study showed significant breast-milk penetration for ethosuximide (Kuhnz et al., 1984).
One Class I study (Nau et al., 1981) and a supporting Class II study (Nau et al., 1984) showed that valproate does not significantly penetrate into breast milk.
One Class I study (Kuhnz et al., 1988) and one Class II study (Nau et al., 1980) provided evidence phenobarbital does not significantly penetrate into breast milk.
Two Class II studies per AED provided evidence that carbamazepine (Kuhnz et al., 1983; Froescher et al., 1984), and phenytoin (Mirkin, 1971; Steen et al., 1982) do not significantly penetrate into breast milk.
The data were inadequate to show consistent evidence of accumulation of any AED in the newborn, including phenobarbital.
Primidone and levetiracetam probably penetrate into breast milk in potentially clinically important amounts (one Class I study and a supporting Class II study or two Class II studies). Gabapentin, lamotrigine, and topiramate possibly penetrate into breast milk in potentially clinically important amounts (one Class II study each). Valproate, phenobarbital, phenytoin, and carbamazepine probably do not penetrate into breast milk in potentially clinically important amounts (one Class I study and a supporting Class II study or two Class II studies). There are insufficient data to determine if ethosuximide penetrates breast milk in clinically important amounts (one Class III study showing significant transfer).
Valproate, phenobarbital, phenytoin, and carbamazepine may be considered as not transferring into breast milk to as great an extent as primidone, levetiracetam, gabapentin, lamotrigine, and topiramate (Level B when compared to primidone and levetiracetam and Level C when compared to gabapentin, lamotrigine, and topiramate).
Because of small sample size, there was no way to analyze the potential contribution of other clinical factors, such as AED polytherapy, on the passive transfer of AEDs to newborns of WWE.
Does indirect exposure to maternally ingested AEDs lead to symptomatic effects in the newborn?
We defined pertinent symptomatic effects as those likely attributable to the AED (e.g., withdrawal, inconsolable fussiness, excessive sedation, lethargy). We searched for controlled studies comparing the frequency of such symptoms in the newborns of WWE on AEDs to WWE not on AEDs. No articles were identified.
There is no evidence to determine if indirect exposure to maternally ingested AEDs has symptomatic effects on the newborns of WWE.
None (Level U).
Certainly many of the AEDs cross through the placenta or into breast milk in measurable concentrations, with some meaningful differences in AEDs, particularly for breast-milk transfer. The clinical consequences for the newborn of ingesting AEDs via breast milk remain sorely underexplored and will continue to produce anxiety in WWE bearing children and all who care for these clinical dyads.
For each of the AEDs, does pregnancy cause a change in the levels of the medication or clearance of the medication?
Articles were included in the analysis if the investigators compared preconception and postpartum AED levels. Articles were classified according to the AAN prognostic classification of evidence scheme (see Appendix e-4b). Using this scheme, pregnancy was considered the predictor, and a change in serum drug levels or drug clearance was considered the outcome.
Serum AED level assays were considered an objective outcome. However, other concerns about the assay’s technical reliability and margin of error were considered as potential sources of bias, and studies were downgraded accordingly. Trough sampling was not a requirement, but inconsistent times of sampling resulted in downgrading. Postpartum values >6 weeks were also accepted as an estimate for nonpregnant baseline. Changes in AED levels in WWE on polytherapy were accepted if it was clearly stated that other AED doses were kept the same. Articles that included WWE on polytherapy were downgraded.
No specific magnitude of change in AED level or clearance was required to be considered clinically important. However, the panel looked for evidence that an increase in seizure frequency was associated with a pregnancy-related decrease in AED levels.
Thirty-one relevant articles were identified by the literature search. In addition, three articles published before 1985 were included in the analysis because they provided the only available information regarding some of the older AEDs. This was considered acceptable because the technology of AED level assays has been stable for decades. Three articles were classified as Class I, five were Class II, and 23 were Class III. For each AED, only the articles with the lowest risk of bias contributing to the conclusions are included in the evidence tables (see Table e-4–e-8).
One Class I study (Pennell et al., 2008) showed that both lamotrigine total and free clearance increased throughout pregnancy, with a peak of 94% (total) and 89% (free) in the third trimester. It is important to note that seizure frequency increased when the lamotrigine level decreased to 65% of the preconceptional individualized target lamotrigine concentration. Two Class II studies (Tran et al., 2002; Pennell et al., 2004) also showed an increase in the lamotrigine clearance. One study (Tran et al., 2002) showed >65% increase in clearance between prepregnancy baseline and the second and third trimesters. The second study (Pennell et al., 2004) showed that lamotrigine clearance increased until 32 weeks of gestation, with a peak of 230% above prepregnancy baseline. All three of these studies showed substantial variability between individuals in the magnitude of the enhanced lamotrigine clearance.
Conclusion. Pregnancy probably causes an increase in the clearance and a decrease in the level of lamotrigine during pregnancy. The decrease in lamotrigine level is associated with an increase in seizure frequency (one Class I and two Class II studies).
One Class I study (Tomson et al., 1994) of 35 women taking carbamazepine during pregnancy showed that total concentration of carbamazepine decreased by 9% in the second trimester and 12% in the third trimester compared to baseline. However, free carbamazepine levels did not change significantly during pregnancy compared to baseline. Carbamazepine–epoxide concentrations, total and free, did not change. Two Class III studies (Battino et al., 1985; Bernus et al., 1995) showed slightly increased clearance (10–27.5%) during pregnancy, but one was confounded by findings only in women on polytherapy with enzyme-inducing AEDs (Bernus et al., 1995). One study (Battino et al., 1985) showed increased carbamazepine–epoxide levels and increased epoxide-to-carbamazepine ratios during pregnancy.
Conclusion. Pregnancy probably causes a small decrease in concentration of carbamazepine (9% in second trimester and 12% in third trimester) (one Class I study).
One Class I study (Tomson et al., 1994) of 22 women taking phenytoin monotherapy showed that total phenytoin concentration decreased in all three trimesters from baseline (max of 61%). Free phenytoin concentrations decreased in the third trimester by 16%. The phenytoin free fraction increased in the second and third trimesters by a maximum of 40%. Plasma phenytoin clearance increased by up to 117% in all three trimesters compared to baseline. Free phenytoin clearance increased in the third trimester by 25%. Three Class II studies (Lander et al., 1981; Bardy et al., 1987; Dickinson et al., 1989) also showed increased clearance and decreased levels during pregnancy.
Conclusion. Pregnancy probably causes an increase in the clearance and a decrease in the level of phenytoin during pregnancy (one Class I study).
Two Class III studies (Christensen et al., 2006; Mazzucchelli et al., 2006) observed a decrease in levels of the active metabolite of oxcarbazepine, monohydroxy derivative (MHD). One study (Mazzucchelli et al., 2006) showed a mean decrease in MHD concentration of 61.5%, maximum in the second trimester. The other study (Christensen et al., 2006) showed that compared to before pregnancy, the mean dose-corrected concentration of MHD decreased by 28% in the first trimester, 26% in the second trimester, and 36% in the third trimester.
Conclusion. Pregnancy possibly causes a decrease in the level of the active oxcarbazepine metabolite, MHD (two Class III studies).
One Class II study (Tomson et al., 2007) showed that concentrations of levetiracetam decreased during pregnancy; maternal plasma concentrations during the third trimester decreased by 60% compared to prepregnancy baseline.
Conclusion. Pregnancy possibly causes a decrease in the level of levetiracetam (one Class II study).
Phenobarbital, valproate, primidone, and ethosuximide
Sufficient monotherapy data are not available to provide evidence for a change in levels or clearance of these AEDs during pregnancy.
Conclusion. Evidence for a change in clearance or level of phenobarbital, valproate, primidone, and ethosuximide during pregnancy is inadequate to reach a conclusion.
- • Monitoring of lamotrigine, carbamazepine, and phenytoin levels during pregnancy should be considered (Level B).
- • Monitoring of levetiracetam and oxcarbazepine (as MHD) levels during pregnancy may be considered (Level C).
- • There is insufficient evidence to support or refute a change in phenobarbital, valproate, primidone, or ethosuximide levels related to pregnancy (Level U), and this lack of evidence should not discourage monitoring levels of these AEDs during pregnancy.
The studies reviewed provide some evidence supporting active monitoring of AED levels during pregnancy. This is especially true for lamotrigine where changes in lamotrigine levels were associated with increases in seizure frequency. It seems reasonable to individualize this monitoring for each patient with the aim of maintaining a level near the preconceptional level, presumably at which the woman with epilepsy was doing well with seizure control. However, the studies reviewed fall short of determining that adoption of an active AED-monitoring program would result in improved seizure control during pregnancy.
Unfortunately, the studies reviewed provided no clear data on the timing of the return to the prepregnancy pharmacokinetic state after pregnancy. One study (Pennell et al., 2008) demonstrated that following an empiric postpartum taper schedule of lamotrigine reduced the occurrence of postpartum toxicity, but more systematic information is needed regarding the pharmacokinetic alterations in AED metabolism postpartum for all AEDs in order to determine the management of AED dosing in the postpartum period.
The authors report the following conflicts of interest:
Dr. Harden has served on the scientific advisory board of Cyberonics, GlaxoSmithKline, UCB Pharma, Valeant, and SK Pharmaceuticals and on the speakers’ bureau of GlaxoSmithKline, Pfizer, UCB Pharma, and Abbott. She serves as an editor of Epilepsy Currents and receives publishing royalties from Elsevier. Dr. Harden has received research funding from Forest, UCB Pharma, Ortho McNeil, and NIH/NINDS. Dr. Harden sees women with epilepsy in her office practice.
Dr. Pennell has served on the Expert Panel for the Keppra Pregnancy Registry sponsored by UCB Pharma. She has received funding for travel from the Northeast Regional Epilepsy Group for speaking at their 2008 Epilepsy Symposium, by the UK Research Council for speaking at the Epilepsy Research UK International Expert Workshop, by UCB Pharma for attending the Executive Panel meeting for the Pregnancy Registry, by the American Epilepsy Society for attending the Board of Directors’ Meeting, by the Epilepsy Foundation for attending the Board of Directors’ and orientation meetings, by the Long Island Jewish Hospital for lecturing at Neurology Grand Rounds, by Duke University for lecturing at Neurology Grand Rounds, by Brigham and Women’s Hospital for lecturing at the Epilepsy Research Conference, by the Milken Foundation for attending Pregnancy Registry meetings, and by Massachusetts General Hospital for speaking at the Annual Teratogens Course. She has received honoraria from Journal Watch Neurology for a contributing article, paid for by Massachusetts Medical Society, NEJM, for review for the Lancet Neurology, the Northeast Regional Epilepsy group for speaking at 2008 Epilepsy Symposium, North Shore Long Island Jewish Health system, Duke University, University of Maryland, the Massachusetts General Hospital for speaking at the postgraduate course in Human Teratogens, and the AAN for speaking and directing annual courses. Dr. Pennell has served as a contributing editor for Epilepsy Currents and is on the editorial board of Epilepsia. Dr. Pennell has received research support from UCB Pharma, Marinus Pharmaceuticals, NIH, HINDS, NIMH, CDC, and Emory University Research Council.
Dr. Koppel reports no disclosures.
Dr. Hovinga estimates less than 10% of his clinical effort is spent on pharmacology consults.
Dr. Gidal has served on the scientific advisory board for GlaxoSmithKline, UCB Pharma, and Abbott Labs and served as an editor for Epilepsy and Behaviour, Ann Pharmacotherapy, and Pharmacists letter. Dr. Gidal has received research support from UCB Pharma.
Dr. Meador serves as a journal editor for Neurology, Journal of Clinical Neurophysiology, Cognitive and Behavioral Neurology, Epilepsy and Behavior, Epilepsy Currents, and Epilepsy.com. He has received research funding from NIH/NINDS, GlaxoSmithKline, Eisai, Marius, Myriad, Neuropace, SAM Technology, and UCB Pharma. Dr. Meador estimates that 30-40% of his clinical effort is spent on EEGs and the clinical care of patients with epilepsy.
Dr. Hopp receives royalties from UpToDate.com electronic medical journal. She has been on the speakers’ bureau of UCB Pharma and GlaxoSmithKline. Dr. Hopp has given testimony in a medico-legal case.
Dr. Ting served on the scientific advisory board of UCB Pharma and has received honoraria from the Epilepsy Foundation of America.
Dr. Hauser has served on the scientific advisory board of Ovation and Valeant. He has served on the editorial board of Acta Neurologica Scandinavia, Neuroepidemiology, and Epilepsy Research. He has received honoraria from Cornell University Symposium on epilepsy and acted as a consultant to Pfizer. Dr. Hauser has received research support from AAMC/CDC, NIH/NINDS, FAA, Mayo Clinic, Hotchkiss Neurological Institute, and has given expert testimony in his role as an FAA consultant.
Dr. Thurman is an employee of the CDC.
Dr. Kaplan has served on the speakers’ bureau of UCB Pharma, GSK, and Ortho McNeil. He serves as an associate editor for Neurophysiologie Clinique, Journal of Clinical Neurophysiology, and Epilepsia. He received royalties from Demos Publications for the books Neurological Disease in Women, Epilepsy A to Z, Imitators of Epilepsy, and Nonconvulsive Status Epilepticus. He has received speaker honoraria from Medical College of South Carolina, Duke University, and Medical College of Virginia, has received research funding from NIH, Schwarz, Ortho McNeil, and Pfizer, and has acted as a consultant for Schering-Plough and Infinite Biological Technologies.
Dr. Robinson reports no disclosures.
Dr. French has served on the scientific advisory board of UCB Pharma, Johnson & Johnson, Eisai, Novartis, Valeant, Icagen, Intranasal, Sepracor, and Marinus. She has received funding for travel to present findings or give lectures from UCB Pharma, Kyowa, Eisai, Johnson & Johnson, Valeant, and GlaxoSmithKline. She has served as an associate editor for Epilepsy Currents and supplement editor for Epileptic Disorders. Dr. French is the president of the Epilepsy Study Consortium, which receives money from multiple pharmaceutical companies (including GlaxoSmithKline, UCB Pharma, Johnson & Johnson, Cyberonics, Schwarz Pharma, Ortho McNeil, Eisai, Jazz Pharmaceuticals, Ovation Pharmaceuticals, Endo Pharmaceuticals, Bial Pharmaceuticals, Neurovista, Valeant Pharmaceuticals, Icagen, Supernus, Intranasal, SK Pharmaceuticals, Taro Pharmaceuticals, Neurotherapeutics, Sepracor, and Novartis) and she consults on behalf of the consortium. Dr. French has received research funding from Johnson &Johnson, Eisai, UCB Pharma, SK Pharmaceuticals, Valeant, Pfizer, NIH, and Epilepsy Research Foundation.
Dr. Wiebe serves on the editorial board of Neurology, Epilepsia, Epilepsy and Behavior, and Canadian Journal of Neurological Sciences.
Dr. Wilner has served on the scientific advisory board of and received funding for travel from GlaxoSmithKline. He receives royalties from Demos Publications for Epilepsy: 199 Answers and Epilepsy in Clinical Practice. He receives board of directors compensation from GlaxoSmithKline.
Dr. Vazquez has served on the scientific advisory board of Eisai, UCB, GSK, and Ortho McNeil. She has received honoraria from UCB, GSK, Ortho McNeil, and Eisai. Dr. Vazquez has served on a speakers’ bureau for Eisai, GSK, Ortho McNeil, UCB, and Novartis.
Dr. Holmes has received research funding from Abbott Labs, GlaxoSmithKline, Eisai, Novartis, Ortho McNeil, and Pfizer.
Dr. Krumholz has served on the Department of Transportation Expert Panel on Commercial Drivers and Epilepsy and has served on the editorial board of The Neurologist and Clinical EEG and Neuroscience. He has received honoraria from the Robert Wood Johnson Medical School for grand rounds.
Dr. Finnell has served on the scientific advisory board of the NEAD study at Emory University, the University of Houston Center for Life Sciences Technology, the NIH, and the NIEHS National Advisory Environmental Health Sciences Council. He has received funding for travel from Fundacion BBVA, NIEHS National Advisory Environmental Health Sciences Council, IKMC Steering Committee, European Epilepsy Meeting, NIH, and AES. Dr. Finnell has served as a journal editor for Birth Defects Research Part A and holds a patent on folate receptor autoantibody assay. He has received honoraria from McGill University-Montreal Neurological Institute and has received research funding from the Centers for Disease Control and Prevention for the National Birth Defects Prevention Study and the Methodist Hospital Research Institute. Dr. Finnell has given expert testimony, prepared affadavits, and acted as a witness regarding legal proceedings related to the topic of this manuscript.
Ms. Shafer has served on the scientific advisory board for GlaxoSmithKline, has received funding for travel from the Epilepsy Therapy Project, and acts as a reviewer for Epilepsy and Behavior and Epilepsia. She has received honoraria from Medscape, American Epilepsy Society, and Cyberonices Nursing Advisory Board. Ms. Shafer is on the speakers’ bureau of the Epilepsy Foundation of Massachusetts and Rhode Island, acts as a consultant to the Epilepsy Therapy Project, and is a contributing writer at epilepsy.com.
Ms. Le Guen reports no disclosures.