title: Prescriptions for category D and X drugs during pregnancy in Taiwan: a population-based study.
abstract: OBJECTIVE
  This study aimed to investigate the most prescribed medications and principle diagnoses for category D and X drugs during pregnancy using a population-based dataset in Taiwan.
  
  
  METHODS
  The data for the present study were sourced from the Taiwan Longitudinal Health Insurance Database 2000. We selected 14 125 women who had live singleton births between 1 January 2009 and 31 December 2011. In total, 217 226 prescriptions prescribed to these pregnant women were identified.
  
  
  RESULTS
  Of the total 217 226 prescriptions, 1.1% were category D or X drugs; in the first, second, and third trimesters of pregnancy, 1.8%, 0.7%, and 0.5% of prescriptions were category D or X drugs, respectively. Progestins (15.3%) and propylthiouracil (10.7%) were the two most frequently prescribed category D or X drugs during pregnancy. In particular, progestins (20.4%) and estrogens (15.6%) were the most frequently prescribed category D or X drug in the first trimester of pregnancy. Propylthiouracil was the most prescribed category D or X drug in the second (20.3%) and third trimesters (23.1%) of pregnancy, respectively. The most common principal diagnosis during pregnancy was "disorders of menstruation and other abnormal bleeding from the female genital tract" (22% of all principal diagnoses for prescribing category D and X drugs).
  
  
  CONCLUSIONS
  Our study found that the physicians obviously reduced the use of category D and X drugs for women after becoming aware that they were pregnant.
authors.affiliation: Graduate Institute of Life Science, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Li-Ting
authors.initials: LT
authors.lastname: Kao
authors.forename: Yi-Hua
authors.initials: YH
authors.lastname: Chen
authors.forename: Herng-Ching
authors.initials: HC
authors.lastname: Lin
authors.forename: Shiu-Dong
authors.initials: SD
authors.lastname: Chung
mesh_terms: D000328:Adult; D016208:Databases, Factual; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D017723:Drug Utilization Review / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011264:Pregnancy Trimesters; D055553:Prescription Drugs / Q000008:administration & dosage / Q000009:adverse effects / Q000145:classification; D045167:Progesterone Congeners / Q000008:administration & dosage; D011441:Propylthiouracil / Q000008:administration & dosage; D013624:Taiwan
chemical_list: D055553:Prescription Drugs; D045167:Progesterone Congeners; D011441:Propylthiouracil
keywords: category D and X drugs; pharmacoepidemiology; pregnancy; prescribing behavior