title: Performance of a checklist to exclude pregnancy at the time of contraceptive initiation among women with a negative urine pregnancy test.
abstract: OBJECTIVE
  Our objective was to measure the sensitivity and specificity of a six-item "pregnancy checklist" at excluding early- or luteal-phase pregnancy among women with a negative urine pregnancy test who were initiating contraception.
  
  
  METHODS
  This was a secondary analysis of the Contraceptive CHOICE Project, a prospective cohort study of 9256 women in the St. Louis region. Women who had a negative urine pregnancy test on the day of enrollment were included in this analysis. Women with a positive urine pregnancy test or without urine pregnancy testing were excluded. We identified all luteal-phase pregnancies that occurred among women with a negative urine pregnancy test. We calculated the sensitivity, specificity, positive predictive value and negative predictive value (NPV) and likelihood ratios of the pregnancy checklist for excluding luteal-phase pregnancies.
  
  
  RESULTS
  There were 6929 women included in this analysis; 69% of these women met at least one checklist criterion to exclude pregnancy ("negative screen"). There were 36 luteal-phase pregnancies (0.5%) subsequently diagnosed among women with a negative urine pregnancy test. The sensitivity and specificity of the checklist were 77.7% and 69.1%, respectively. The NPV of the checklist was 99.8% and the positive predictive value was 1.3%.
  
  
  CONCLUSIONS
  Among women with a negative urine pregnancy test, the pregnancy checklist can be used to safely exclude more than 99% of early pregnancies at the time of contraceptive initiation.
  
  
  CONCLUSIONS
  In patients with a negative urine pregnancy test, a pregnancy checklist using six criteria based on patient history has high NPV in excluding early pregnancy. This checklist can be used to facilitate same-day initiation of contraceptive methods, including long-acting reversible contraception. Although the checklist had a high false positive rate, initiation of contraception should not be delayed in women with a "positive screen." Rather women who desire an intrauterine device or implant can be "bridged" with a shorter-acting method until pregnancy can be excluded.
authors.affiliation: Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Jaspur
authors.initials: J
authors.lastname: Min
authors.affiliation: Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Buckel
authors.affiliation: Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Gina M
authors.initials: GM
authors.lastname: Secura
authors.affiliation: Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Jeffrey F
authors.initials: JF
authors.lastname: Peipert
authors.affiliation: Division of Clinical Research, Department of Obstetrics and Gynecology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA. Electronic address: maddent@wustl.edu.
authors.forename: Tessa
authors.initials: T
authors.lastname: Madden
mesh_terms: D000293:Adolescent; D000328:Adult; D057189:Checklist; D015331:Cohort Studies; D003271:Contraceptive Agents, Female / Q000008:administration & dosage; D000075202:Contraindications; D004343:Drug Implants; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D007087:Illinois; D007434:Intrauterine Devices; D008183:Luteal Phase / Q000652:urine*; D008875:Middle Aged; D008923:Missouri; D010349:Patient Compliance; D011247:Pregnancy; D011258:Pregnancy Tests; D011261:Pregnancy Trimester, First; D049168:Pregnancy, Unplanned / Q000652:urine*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D003271:Contraceptive Agents, Female; D004343:Drug Implants
keywords: Contraception; Contraceptive initiation; Pregnancy checklist; Pregnancy testing