Summary Purpose Antiepileptic drugs may cause congenital malformations. Less is known about the effect on development in infancy and childhood. The aim of this study was to examine whether exposure to antiepileptic drugs during pregnancy has an impact on early child development. Methods From mid-year 1999 through December 2008, children of mothers recruited at 13–17 weeks of pregnancy were studied in the ongoing prospective Norwegian Mother and Child Cohort Study. Information on birth outcomes were obtained from the Medical Birth Registry (108,264 –children), and mothers reported on their child’s motor development, language, social skills, and autistic traits using items from standardized screening tools at 18 months (61,351 children) and 36 months of age (44,147 children). The relative risk of adverse outcomes in children according to maternal or paternal epilepsy with and without prenatal exposure to antiepileptic drugs was estimated as odds ratios (ORs), using logistic regression with adjustment for maternal age, parity, education, smoking, depression/anxiety, folate-supplementation, and child congenital malformation or low birth weight. Key findings A total of 333 children were exposed to antiepileptic drugs in utero. At 18 months, the exposed children had increased risk of abnormal scores for gross motor skills (7.1 % vs. 2.9 %; OR, 2.0; 95 % Confidence Interval [CI], 1.1–3.7) and autistic traits (3.5 % vs. 0.9 %; OR, 2.7; CI, 1.1–6.7) compared to children of parents without epilepsy. At 36 months, the exposed children had increased risk of abnormal score for gross motor skills (7.5 % vs. 3.3 %; OR, 2.2; CI, 1.1–4.2), sentence skills (11.2 % vs. 4.8 %; OR, 2.1; CI, 1.2–3.6), and autistic traits (6.0 % vs. 1.5 %; OR, 3.4; CI, 1.6–7.0). The drug-exposed children also had increased risk of congenital malformations (6.1 % vs. 2.9 %; OR, 2.1; CI, 1.4–3.4), but exclusion of congenital malformations did not affect the risk of adverse development. Children born to women with epilepsy who did not use antiepileptic drugs had no increased risks. Children of fathers with epilepsy generally scored within the normal range. Significance Exposure to antiepileptic drugs during pregnancy is associated with adverse development at 18 and 36 months of age, measured as low scores within key developmental domains rated by mothers. Exposures to valproate, lamotrigine, carbamazepine, or multiple antiepileptic drugs were associated with adverse outcome within different developmental domains.

The primary aim of this study was to assess the risks of fetal growth restriction and birth defects in children exposed prenatally to newer and older antiepileptic drugs, using an unselected epilepsy cohort. Deliveries recorded in the compulsory Medical Birth Registry of Norway 1999-2011 formed the study population. All 2,600 children exposed to antiepileptic drugs during pregnancy were compared to all 771,412 unexposed children born to women without epilepsy. Children of untreated mothers with epilepsy served as an internal control group. The main outcomes were small for gestational age birth weight and head circumference, and major congenital malformations. Children exposed to antiepileptic drugs had a moderate risk of growth restriction. Infants exposed to topiramate had a considerable risk of microcephaly (11.4 vs. 2.4 %; OR 4.8; CI 2.5-9.3) and small for gestational age birth weight (24.4 vs. 8.9 %; OR 3.1; 95 % CI 1.9-5.3). Carbamazepine, lamotrigine, levetiracetam, oxcarbazepine, gabapentin, and pregabalin had low malformation rates, whereas topiramate tended to have an elevated malformation rate. Valproate monotherapy was associated with a significant risk of birth defects (6.3 vs. 2.9 %; OR 2.5; CI 1.6-3.8), and specifically with septal heart defects and hypospadias. For mothers using valproate, the presence of major birth defect in one child was associated with a markedly increased risk for the siblings (42.9 vs. 6.7 %; OR 10.4; CI 2.3-46.7). Children of untreated mothers with epilepsy had malformation risk similar to the reference group. In conclusion, topiramate was associated with a substantial risk of fetal growth restriction, and possibly an increased malformation rate. Other newer-generation antiepileptic drugs had a low malformation rate. Valproate monotherapy had a significant malformation risk, especially in repeated pregnancies.

SUMMARYPurpose: To investigate pregnancy, delivery, and child outcome in an unselected population of women with both treated and untreated epilepsy. Methods: In the compulsory Medical Birth Registry of Norway, all 2,861 deliveries by women with epilepsy recorded from 1999-2005 were compared to all 369,267 nonepilepsy deliveries in the same period. Results: The majority (66%, n = 1900) in the epilepsy group did not use antiepileptic drugs (AEDs) during pregnancy. A total of 961 epilepsy-pregnancies were exposed to AEDs. Compared to nonepilepsy controls, AED-exposed infants were more often preterm (p = 0.01), and more often had birth weight <2,500 g (p < 0.001), head circumference <2.5 percentile (p < 0.001), and low Apgar score (p = 0.03). Small-for-gestational-age (SGA) infants (<10 percentile) occurred more frequently in both AED-exposed (p = 0.05) and unexposed (p = 0.02) epilepsy-pregnancies. Frequency of major congenital malformations (MCMs) was 2.8% (n = 81) in the epilepsy group versus 2.5% in controls (p = 0.3). Increased risk for MCMs could be demonstrated only for exposure to valproate (5.6%, p = 0.005) and AED polytherapy (6.1%, p = 0.02). Neonatal spina bifida was not significantly increased, but was a major indication for elective pregnancy termination among women with epilepsy. Cesarean section was performed more often in maternal epilepsy, regardless of AED-exposure (p < 0.001). Discussion: Adverse pregnancy and birth outcome in women with epilepsy is mainly confined to AEDexposed pregnancies, although some risks are associated also with untreated epilepsy. The risk for congenital malformations was lower than previously reported. This could be due to a shift in AED selection, folic acid supplement, or possibly reflect the true risks in an unselected epilepsy population.