title: Discontinuation of antipsychotic medication in pregnancy: a cohort study.
abstract: BACKGROUND
  Women prescribed antipsychotics face the dilemma on whether to continue medication in pregnancy in terms of balancing risks and benefits. Previous research on other psychotropic medications suggests that many women discontinue treatment in early pregnancy. However, very limited evidence exists on discontinuation of antipsychotic medication.
  
  
  METHODS
  We identified 495,953 pregnant women from THIN primary care database. Kaplan-Meier plots were used to examine time to last antipsychotic prescription. Poisson regression was used to examine characteristics of those who stopped treatment during pregnancy.
  
  
  RESULTS
  There has been an overall increase in prevalence of antipsychotic prescribing since 2007. However, antipsychotics were more likely to be stopped in pregnant than non-pregnant women. Only 107/279 (38%) of women on atypical antipsychotics and 39/207 (19%) of women on typical antipsychotics before pregnancy still received treatment at the start of third trimester. Older women were more likely to continue typical antipsychotic treatment in pregnancy (35+ versus <25 years risk ratio: 3.09 [95% CI 1.76, 5.44]). Likewise, those who received typical antipsychotics for longer periods before were most likely to continue treatment in pregnancy (12+ versus <6 months: RR: 3.12 [95% CI 1.97, 4.95]). For atypical antipsychotics length and dose of prior prescribing were also associated with continuation in pregnancy.
  
  
  CONCLUSIONS
  Pregnancy was a major determinant of cessation of antipsychotics. Only 38% of women on atypical and 19% on typical antipsychotics were still prescribed the drug in the third trimester. Duration of prior treatment, maternal age as well as dose was significantly associated with continued treatment of antipsychotics in pregnancy.
authors.affiliation: Department of Primary Care and Population Health, UCL, Rowland Hill St., London NW3 2PF, United Kingdom. Electronic address: i.petersen@ucl.ac.uk.
authors.forename: Irene
authors.initials: I
authors.lastname: Petersen
authors.affiliation: Department of Primary Care and Population Health, UCL, Rowland Hill St., London NW3 2PF, United Kingdom.
authors.forename: Rachel L
authors.initials: RL
authors.lastname: McCrea
authors.affiliation: Division of Psychiatry, UCL, Charles Bell House, Riding House Street, London W1W 7EJ, United Kingdom.
authors.forename: David J P
authors.initials: DJ
authors.lastname: Osborn
authors.affiliation: Department of Medical Statistics, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom.
authors.forename: Stephen
authors.initials: S
authors.lastname: Evans
authors.affiliation: The McPin Foundation, 32-36 Loman Street, London SE1 0EH, United Kingdom.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Pinfold
authors.affiliation: University Department of Psychiatry, Warneford Hospital, Oxford OX37JX, United Kingdom.
authors.forename: Phil J
authors.initials: PJ
authors.lastname: Cowen
authors.affiliation: Centre of Paediatric Epidemiology and Biostatistics, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, United Kingdom.
authors.forename: Ruth
authors.initials: R
authors.lastname: Gilbert
authors.affiliation: Department of Primary Care and Population Health, UCL, Rowland Hill St., London NW3 2PF, United Kingdom.
authors.forename: Irwin
authors.initials: I
authors.lastname: Nazareth
mesh_terms: D000328:Adult; D017677:Age Distribution; D014150:Antipsychotic Agents / Q000009:adverse effects*; D015331:Cohort Studies; D004363:Drug Utilization / Q000706:statistics & numerical data; D064420:Drug-Related Side Effects and Adverse Reactions / Q000453:epidemiology*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D011247:Pregnancy; D011248:Pregnancy Complications / Q000139:chemically induced* / Q000453:epidemiology*; D012372:ROC Curve; D012559:Schizophrenia / Q000188:drug therapy*; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents
keywords: Antipsychotics; Medicine discontinuation; Pregnancy; The Health Improvement Network