title: Dispensing of benzodiazepines and benzodiazepine-related drugs to pregnant women: a population-based cohort study.
abstract: OBJECTIVE
  The study aimed to describe the dispensing of benzodiazepines and benzodiazepine-related drugs (z-hypnotics) to pregnant women and to study the characteristics of these women and the extent of co-medication.
  
  
  METHODS
  A population-based cohort study was conducted based on the linkage of nationwide registries: the Medical Birth Registry of Norway and the Norwegian Prescription Database. The data covers dispensed drugs to women 3 months prior to, during and after pregnancy. The study population consisted of 345,703 singleton pregnancies during a period starting 1 April 2004 or later and ending before 1 January 2011.
  
  
  RESULTS
  In 5,135 (1.5 %) of the pregnancies, the women were dispensed a benzodiazepine or z-hypnotic at least once. Of these, 68.5 % filled just one prescription for the duration of the pregnancy. Prevalence was lower in pregnancy than before and after pregnancy. The median total amount of benzodiazepines and/or z-hypnotics dispensed during pregnancy was 15 defined daily doses (DDDs), while the 25 % receiving the largest amounts got 40 DDDs or more. Five hundred eleven women, the 10 % that were prescribed the largest amounts during pregnancy, received a median amount of 220 DDDs. Women receiving these drugs were older, more often smokers, without a partner and suffering from chronic disease. Of the medicated pregnant women, 19.6 % and 19.3 % were also prescribed an opioid and antidepressant, respectively.
  
  
  CONCLUSIONS
  The use of benzodiazepines and z-hypnotic drugs during pregnancy was not very prevalent in Norway. However, our findings imply that there is a substantial number of pregnancies where these drugs are dispensed often and/or in large quantities and where co-medication occurred.
authors.affiliation: Faculty of Medicine, University of Oslo, P.O. 1078, Blindern, 0316, Oslo, Norway, b.s.riska@studmed.uio.no.
authors.forename: Brit Solvor
authors.initials: BS
authors.lastname: Riska
authors.forename: Svetlana
authors.initials: S
authors.lastname: Skurtveit
authors.forename: Kari
authors.initials: K
authors.lastname: Furu
authors.forename: Anders
authors.initials: A
authors.lastname: Engeland
authors.forename: Marte
authors.initials: M
authors.lastname: Handal
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000627:therapeutic use; D000928:Antidepressive Agents / Q000627:therapeutic use; D001569:Benzodiazepines / Q000627:therapeutic use*; D016208:Databases, Factual; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000627:therapeutic use*; D009664:Norway / Q000453:epidemiology; D011247:Pregnancy / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D000701:Analgesics, Opioid; D000928:Antidepressive Agents; D006993:Hypnotics and Sedatives; D001569:Benzodiazepines