Adverse pregnancy outcomes in women exposed to gabapentin and pregabalin: data from a population-based study

We undertook a population-based study to assess the comparative risk of spontaneous abortions, terminations of pregnancy (TOPs), major birth defects (MBDs), preterm births and small for gestational age (SGA) infants following intrauterine antiepileptic drug (AED) exposure in the Emilia Romagna region, Northern Italy (4 million inhabitants) over a 3-year period (2009–2011). The study was approved by the Local Ethical Committee and authorised by the Hospital Management Executive. Data were obtained from official regional registries: Certificates of Delivery Assistance (CedAP) for deliveries (>99% coverage of live births and stillbirths) and Hospital Discharge Cards collecting the International Classification of Diseases (ICD) codes of all the discharge diagnoses, for abortions . AED exposure was based on reimbursed prescription databases as AEDs are supplied and reimbursed by medical prescription in Italy; all drugs registered as AEDs and redeemed with ATC code N03 were considered. MBDs were taken from the Registry of Congenital Malformations (IMER) recording MBDs detected by paediatricians in stillbirths and in live births during the first week of the infant’s life (coverage >95% of births). Each recording from the first three registries contains a unique anonymous code identifying each citizen and linking information among registries. Recordings from the IMER are routinely linked to the CeDAP and consequently to the others, using an additional procedure (correct linkage >98% of the sample). All data were anonymised at the regional source of data to protect patient privacy according to Italian legislation. For the deliveries cohort, the exposure period was based on the date of delivery and gestational age. For the …