Fertility and Sterility
Volume 88, Issue 3 , Pages 572-580 , September 2007

Clinical information does not improve the performance of mathematical models in predicting the outcome of pregnancies of unknown location

  • George Condous, M.R.C.O.G., F.R.A.N.Z.C.O.G.

      Affiliations

    • Early Pregnancy, Gynaecological Ultrasound and MAS Unit, St. George's, University of London, London, United Kingdom
    • Early Pregnancy and Advanced Endosurgery Unit, Nepean Clinical School, Nepean Hospital, University of Sydney, Sydney, Australia
    • Corresponding Author InformationReprint requests: George Condous, M.R.C.O.G., F.R.A.N.Z.C.O.G., Associate Professor in Gynaecology, Early Pregnancy and Advanced Endosurgery Unit, Nepean Clinical School, Nepean Hospital, University of Sydney, Penrith, NSW, 2750, Sydney, Australia (FAX: 612 47341817).
    • ,
  • Ben Van Calster, M.S.

      Affiliations

    • Department of Electrical Engineering ESAT-SCD
    • ,
  • Emma Kirk, M.B.B.S.

      Affiliations

    • Early Pregnancy, Gynaecological Ultrasound and MAS Unit, St. George's, University of London, London, United Kingdom
    • ,
  • Zara Haider, M.R.C.O.G.

      Affiliations

    • Early Pregnancy, Gynaecological Ultrasound and MAS Unit, St. George's, University of London, London, United Kingdom
    • ,
  • Dirk Timmerman, M.D., Ph.D.

      Affiliations

    • Department of Obstetrics and Gynecology, University Hospital Gasthuisberg, Katholieke Universiteit Leuven, Leuven, Belgium
    • ,
  • Sabine Van Huffel, Ph.D.

      Affiliations

    • Department of Electrical Engineering ESAT-SCD
    • ,
  • Tom Bourne, F.R.C.O.G., Ph.D.

      Affiliations

    • Early Pregnancy, Gynaecological Ultrasound and MAS Unit, St. George's, University of London, London, United Kingdom

Received 21 June 2006 ,Revised 9 December 2006 ,Accepted 9 December 2006.

References 

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  2. Hahlin M, Thorburn J, Bryman I. The expectant management of early pregnancies of uncertain site. Hum Reprod. 1995;10:1223–1227
  3. Dart R, Howard K. Subclassification of indeterminate pelvic ultrasonograms: stratifying the risk of ectopic pregnancy. Ann Emerg Med. 1998;5:313–319
  4. Banerjee S, Aslam N, Woelfer B, Lawrence A, Elson J, Jurkovic D. Expectant management of early pregnancies of unknown location: a prospective evaluation of methods to predict spontaneous resolution of pregnancy. Br J Obstet Gynaecol. 2001;108:158–163
  5. Condous G, Okaro E, Khalid A, Timmerman D, Lu C, Zhou Y, et al. The use of a new logistic regression model for predicting the outcome of pregnancies of unknown location. Hum Reprod. 2004;19:1900–1910
  6. Condous G, Van Calster B, Kirk E, Haider Z, Timmerman D, Van Huffel S, et al. Prediction of ectopic pregnancy in women with a pregnancy of unknown location. Ultrasound Obstet Gynecol. 2007;in press
  7. Kirk E, Condous G, Haider Z, Lu C, Van Huffel S, Timmerman D, et al. The practical application of a mathematical model to predict the outcome of pregnancies of unknown location. Ultrasound Obstet Gynecol. 2006;27:311–315
  8. Condous G, Kirk E, Lu C, Van Huffel S, Gevaert O, De Moor B, et al. Diagnostic accuracy of varying discriminatory zones for the prediction of ectopic pregnancy in women with a pregnancy of unknown location. Ultrasound Obstet Gynecol. 2005;26:770–775
  9. Condous G, Kirk E, Van Calster B, Van Huffel S, Timmerman D, Bourne T. Failing pregnancies of unknown location: a prospective evaluation of the human chorionic gonadotrophin ratio. Br J Obstet Gynaecol. 2006;113:521–527
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  11. Mol B, Van der Veen F, Bossuyt P. Implementation of probabilistic decision rules improves the predictive values of algorithms in the diagnostic management of ectopic pregnancy. Hum Reprod. 1999;14:2855–2862
  12. Condous G, Kirk E, Syed A, Van Calster B, Van Huffel S, Timmerman D, et al. Do levels of serum cancer antigen 125 and creatine kinase predict the outcome in pregnancies of unknown location?. Hum Reprod. 2005;20:3348–3354
  13. Warren WB, Timor-Tritsch IE, Peisner DB, Raju S, Rosen MG. Dating the early pregnancy by sequential appearance of embryonic structures. Am J Obstet Gynecol. 1989;161:747–753
  14. Condous G, Okaro E, Khalid A, Lu C, Van Huffel S, Timmerman D, et al. The accuracy of transvaginal ultrasonography for the diagnosis of ectopic pregnancy prior to surgery. Hum Reprod. 2005;20:1404–1409
  15. Condous G, Lu C, Van Huffel S, Timmerman D, Bourne T. Human chorionic gonadotrophin and progesterone levels for the investigation of pregnancies of unknown location. Int J Gynaecol Obstet. 2004;86:351–357
  16. Condous G, Okaro E, Khalid A, Lu C, Van Huffel S, Timmerman D, et al. A prospective evaluation of a single-visit strategy to manage pregnancies of unknown location. Hum Reprod. 2005;20:1398–1403
  17. Condous G, Okaro E, Khalid A, Bourne T. Do we need to follow up complete miscarriages with serum human chorionic gonadotrophin levels?. Br J Obstet Gynaecol. 2005;112:827–829
  18. Agresti A. An introduction to categorical data analysis. New York: Wiley & Sons; 1996;
  19. Khan KS, Chien PF, Dwarakanath LS. Logistic regression models in obstetrics and gynecology literature. Obstet Gynecol. 1999;93:1014–1020
  20. Hanley JA, McNeil BJ. The meaning and use of the area under a receiver operating characteristic (ROC) curve. Radiology. 1982;143:29–36
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  22. Gevaert O, De Smet F, Kirk E, Van Calster B, Bourne T, Van Huffel S, et al. Predicting the outcome of pregnancies of unknown location: Bayesian networks with expert prior information compared with logistic regression. Hum Reprod. 2006;21:824–831
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  24. Mol BW, Ankum WM, Bossuyt PM, Van der Veen F. Contraception and the risk of ectopic pregnancy. Contraception. 1995;52:337–341

 Supported by the Research Council of the Katholieke Universiteit Leuven (GOA-MEFISTO 666, GOA-AMBioRICS), the Flemish Government (FWO: projects G.0407.02/G.0269.02/G.0360.05, research communities ICCoS and ANMMM), the Belgian Federal Government (DWTC: IUAP IV-02 [1996–2001] and IUAP V-22 [2002–2006]), and the E. U. (PDT-COIL: contract N N E5/200 1/887; BIOPATTERN: contract FP6–2002-IST 508803; eTU MOR: contract FP6–2002-LIFESCIHEALTH 503094).

PII: S0015-0282(07)00040-4

doi: 10.1016/j.fertnstert.2006.12.015

Fertility and Sterility
Volume 88, Issue 3 , Pages 572-580 , September 2007

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