Figure 3. Child IQ at 6 years, by exposure to maternal antiepileptic drug use and periconceptional folate.

Mean (95% CIs) are shown for folate (solid lines) and no folate (dashed lines). For carbamazepine, 56 children were exposed to periconceptional folate (mean IQ 106, 95% CI 102–110) and 38 children were not (103, 98–107); for lamotrigine 60 children were exposed to periconceptional folate (111, 108–115) and 40 children were not (103, 98–107); for phenytoin, 23 children were exposed to periconceptional folate (112, 107–118) and 32 children were not (103, 98–108); for valproate, 40 children were exposed to periconceptional folate (98, 94–103) and 22 children were not (96, 91–102); for all antiepileptic drugs combined, 179 children were exposed to periconceptional folate (107, 105–109) and 132 children were not (102, 99–105). Appendix p 7 shows means and analyses for dose effects. IQ=intelligence quotient.