Kurt T Barnhart

University of Pennsylvania, Filadelfia, Pennsylvania, United States

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Publications (324)1647.51 Total impact

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    ABSTRACT: Background The standard therapy for women with unexplained infertility is gonadotropin or clomiphene citrate. Ovarian stimulation with letrozole has been proposed to reduce multiple gestations while maintaining live birth rates. Methods We enrolled couples with unexplained infertility in a multicenter, randomized trial. Ovulatory women 18 to 40 years of age with at least one patent fallopian tube were randomly assigned to ovarian stimulation (up to four cycles) with gonadotropin (301 women), clomiphene (300), or letrozole (299). The primary outcome was the rate of multiple gestations among women with clinical pregnancies. Results After treatment with gonadotropin, clomiphene, or letrozole, clinical pregnancies occurred in 35.5%, 28.3%, and 22.4% of cycles, and live birth in 32.2%, 23.3%, and 18.7%, respectively; pregnancy rates with letrozole were significantly lower than the rates with standard therapy (gonadotropin or clomiphene) (P=0.003) or gonadotropin alone (P<0.001) but not with clomiphene alone (P=0.10). Among ongoing pregnancies with fetal heart activity, the multiple gestation rate with letrozole (9 of 67 pregnancies, 13%) did not differ significantly from the rate with gonadotropin or clomiphene (42 of 192, 22%; P=0.15) or clomiphene alone (8 of 85, 9%; P=0.44) but was lower than the rate with gonadotropin alone (34 of 107, 32%; P=0.006). All multiple gestations in the clomiphene and letrozole groups were twins, whereas gonadotropin treatment resulted in 24 twin and 10 triplet gestations. There were no significant differences among groups in the frequencies of congenital anomalies or major fetal and neonatal complications. Conclusions In women with unexplained infertility, ovarian stimulation with letrozole resulted in a significantly lower frequency of multiple gestation but also a lower frequency of live birth, as compared with gonadotropin but not as compared with clomiphene. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01044862 .).
    New England Journal of Medicine 09/2015; 373(13):1230-1240. DOI:10.1056/NEJMoa1414827 · 55.87 Impact Factor
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    ABSTRACT: Is salpingotomy cost effective compared with salpingectomy in women with tubal pregnancy and a healthy contralateral tube? Salpingotomy is not cost effective over salpingectomy as a surgical procedure for tubal pregnancy, as its costs are higher without a better ongoing pregnancy rate while risks of persistent trophoblast are higher. Women with a tubal pregnancy treated by salpingotomy or salpingectomy in the presence of a healthy contralateral tube have comparable ongoing pregnancy rates by natural conception. Salpingotomy bears the risk of persistent trophoblast necessitating additional medical or surgical treatment. Repeat ectopic pregnancy occurs slightly more often after salpingotomy compared with salpingectomy. Both consequences imply potentially higher costs after salpingotomy. We performed an economic evaluation of salpingotomy compared with salpingectomy in an international multicentre randomized controlled trial in women with a tubal pregnancy and a healthy contralateral tube. Between 24 September 2004 and 29 November 2011, women were allocated to salpingotomy (n = 215) or salpingectomy (n = 231). Fertility follow-up was done up to 36 months post-operatively. We performed a cost-effectiveness analysis from a hospital perspective. We compared the direct medical costs of salpingotomy and salpingectomy until an ongoing pregnancy occurred by natural conception within a time horizon of 36 months. Direct medical costs included the surgical treatment of the initial tubal pregnancy, readmissions including reinterventions, treatment for persistent trophoblast and interventions for repeat ectopic pregnancy. The analysis was performed according to the intention-to-treat principle. Mean direct medical costs per woman in the salpingotomy group and in the salpingectomy group were €3319 versus €2958, respectively, with a mean difference of €361 (95% confidence interval €217 to €515). Salpingotomy resulted in a marginally higher ongoing pregnancy rate by natural conception compared with salpingectomy leading to an incremental cost-effectiveness ratio €40 982 (95% confidence interval -€130 319 to €145 491) per ongoing pregnancy. Since salpingotomy resulted in more additional treatments for persistent trophoblast and interventions for repeat ectopic pregnancy, the incremental cost-effectiveness ratio was not informative. Costs of any subsequent IVF cycles were not included in this analysis. The analysis was limited to the perspective of the hospital. However, a small treatment benefit of salpingotomy might be enough to cover the costs of subsequent IVF. This uncertainty should be incorporated in shared decision-making. Whether salpingotomy should be offered depends on society's willingness to pay for an additional child. Netherlands Organisation for Health Research and Development, Region Västra Götaland Health & Medical Care Committee. ISRCTN37002267. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Human Reproduction 07/2015; 30(9). DOI:10.1093/humrep/dev162 · 4.57 Impact Factor
  • Kurt T Barnhart · Alan H DeCherney
    Fertility and sterility 05/2015; 104(1). DOI:10.1016/j.fertnstert.2015.04.034 · 4.59 Impact Factor
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    ABSTRACT: To estimate contraceptive efficacy, safety, acceptability, and fit of a single-size diaphragm used with contraceptive gel. We conducted a multicenter trial in which 450 couples used the single-size diaphragm, 300 randomized to acid-buffering gel and 150 to nonoxynol-9, for at least 190 days and six menstrual cycles. Visits were at enrollment and after menstrual cycles 1, 3, and 6. Study outcomes included pregnancy probability, safety, acceptability, and fit. Pregnancy and safety were compared with an historical control group who used a standard diaphragm with these gels. Most (439/450 [98%]) women could be fitted with the single-size diaphragm. A total of 421 of 450 (94%) provided follow-up. The 35 study pregnancies yielded 6-month Kaplan-Meier cumulative typical use pregnancy probabilities per 100 women with 95% confidence intervals (CIs) of 10.4 (6.9-14.0) for all users and 9.6 (5.5-13.6) and 12.5 (5.4-19.5) with acid-buffering gel and nonoxynol-9, respectively. Historical control analysis yielded a propensity score-adjusted estimate of this pregnancy probability for the single-size diaphragm of 11.3 compared with 10.7 per 100 women for the standard diaphragm ([rounded] difference 0.7, 95% CI -3.6 to 4.9). Approximately half (51%) reported at least one urogenital event but compared favorably to the standard diaphragm in historical control analysis. Most (282/342 [82%]) liked the diaphragm. Results suggest that if provided by a clinician, 94% (95% CI 92-96%) could insert, correctly position, and remove the diaphragm. The single-size diaphragm was safe, as effective as a standard diaphragm, and acceptable when used with contraceptive gel. ClinicalTrials.gov, www.clinicaltrials.gov, NCT00578877. LEVEL OF EVIDENCE:: II.
    Obstetrics and Gynecology 03/2015; 125(4). DOI:10.1097/AOG.0000000000000721 · 5.18 Impact Factor
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    ABSTRACT: To identify baseline characteristics of women with unexplained infertility to determine whether treatment with an aromatase inhibitor will result in a lower rate of multiple gestations than current standard ovulation induction medications. Randomized, prospective clinical trial. Multicenter university-based clinical practices. A total of 900 couples with unexplained infertility. Collection of baseline demographics, blood samples, and ultrasonographic assessments. Demographic, laboratory, imaging, and survey characteristics. Demographic characteristics of women receiving clomiphene citrate (CC), letrozole, or gonadotropins for ovarian stimulation were very consistent. Their mean age was 32.2 ± 4.4 years and infertility duration was 34.7 ± 25.7 months, with 59% primary infertility. More than one-third of the women were current or past smokers. The mean body mass index (BMI) was 27 and mean antimüllerian hormone level was 2.6; only 11 women (1.3%) had antral follicle counts of <5. Similar observations were identified for hormonal profiles, ultrasound characterization of the ovaries, semen parameters, and quality of life assessments in both male and female partners. The cause of infertility in the couples recruited to this treatment trial is elusive, as the women were regularly ovulating and had evidence of good ovarian reserve both by basal FSH, antimüllerian hormone levels, and antral follicle counts; the male partners had normal semen parameters. The three treatment groups have common baseline characteristics, thereby providing comparable patient populations for testing the hypothesis that use of letrozole for ovarian stimulation can reduce the rates of multiples from that observed with gonadotropin and CC treatment. NCT 01044862. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
    Fertility and Sterility 02/2015; 103(4). DOI:10.1016/j.fertnstert.2014.12.130 · 4.59 Impact Factor
  • Kurt T Barnhart
    American Journal of Obstetrics and Gynecology 01/2015; 212(1):4-6. DOI:10.1016/j.ajog.2014.07.042 · 4.70 Impact Factor
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    ABSTRACT: Infertility is a common disability, and is listed by the World Health Organization as the fifth leading serious disability among populations under the age of 60 years. Effective therapies exist, but evidence-based options are uncommon. Clinical trials in infertility treatment lack uniform guidelines for reporting methodology and results. Clinical trials in infertility are unique in that they usually involve, at minimum, two individuals who may receive or participate in treatment, i.e., a woman and a man, and if treatment is successful, a third individual is followed in the trial, i.e., an infant, who is also the desired outcome of the treatment. This tripartite involvement of three unique humans in a clinical trial is unprecedented in other clinical trials, and the Consolidated Standards of Reporting Trials (CONSORT) guidelines leave several areas of uncertainty regarding what to report with multiple individuals involved. Two of the individuals, the woman seeking pregnancy and the infant, have been classified ethically as vulnerable populations requiring careful collection of all adverse events, including congenital anomaly rates. Participants may experience varied risk and benefit from the trial; for example, multiple pregnancy may be desired by the father, feared by the mother, and fatal to the infant. The outcome of primary interest to participants, i.e., a live birth, is separated from the actual treatment by 9 months and subject to confounding influences from other factors. These myriad issues lead to incomplete and inconsistent reporting of results. We developed this modification to the CONSORT statement, which we describe and justify in this document, to report the items of vital interest to infertile couples, clinicians, and the public that should be collected in an infertility trial.
    Fertility and Sterility 10/2014; 102(4). · 4.59 Impact Factor
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    ABSTRACT: Clinical trials testing infertility treatments often do not report on the major outcomes of interest to patients and clinicians and the public (such as live birth) nor on the harms, including maternal risks during pregnancy and fetal anomalies. This is complicated by the multiple participants in infertility trials which may include a woman (mother), a man (father), and result in a third individual if successful, their offspring (child), who is also the desired outcome of treatment. The primary outcome of interest and many adverse events occur after cessation of infertility treatment and during pregnancy and the puerperium, which create a unique burden of follow-up for clinical trial investigators and participants. In 2013, because of the inconsistencies in trial reporting and the unique aspects of infertility trials not adequately addressed by existing Consolidated Standards of Reporting Trials (CONSORT) statements, we convened a consensus conference in Harbin, China, with the aim of planning modifications to the CONSORT checklist to improve the quality of reporting of clinical trials testing infertility treatment. The consensus group recommended that the preferred primary outcome of all infertility trials is live birth (defined as any delivery of a live infant ≥20 weeks gestations) or cumulative live birth, defined as the live birth per women over a defined time period (or number of treatment cycles). In addition, harms to all participants should be systematically collected and reported, including during the intervention, any resulting pregnancy, and during the neonatal period. Routine information should be collected and reported on both male and female participants in the trial. We propose to track the change in quality that these guidelines may produce in published trials testing infertility treatments. Our ultimate goal is to increase the transparency of benefits and risks of infertility treatments to provide better medical care to affected individuals and couples.
    Fertility and Sterility 09/2014; 102(4). DOI:10.1093/humrep/deu218 · 4.59 Impact Factor
  • Kurt T. Barnhart
    Fertility and Sterility 09/2014; 102(4). DOI:10.1016/j.fertnstert.2014.08.026 · 4.59 Impact Factor
  • M.B. Moravek · K.T. Barnhart · J.C. Robins
    Fertility and Sterility 09/2014; 102(3):e239. DOI:10.1016/j.fertnstert.2014.07.810 · 4.59 Impact Factor
  • S. Senapati · M.D. Sammel · S. Boudhar · C.B. Morse · K.T. Barnhart
    Fertility and Sterility 09/2014; 102(3):e48-e49. DOI:10.1016/j.fertnstert.2014.07.170 · 4.59 Impact Factor
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    ABSTRACT: Background: Clomiphene is the current first-line infertility treatment in women with the polycystic ovary syndrome, but aromatase inhibitors, including letrozole, might result in better pregnancy outcomes. Methods: In this double-blind, multicenter trial, we randomly assigned 750 women, in a 1:1 ratio, to receive letrozole or clomiphene for up to five treatment cycles, with visits to determine ovulation and pregnancy, followed by tracking of pregnancies. The polycystic ovary syndrome was defined according to modified Rotterdam criteria (anovulation with either hyperandrogenism or polycystic ovaries). Participants were 18 to 40 years of age, had at least one patent fallopian tube and a normal uterine cavity, and had a male partner with a sperm concentration of at least 14 million per milliliter; the women and their partners agreed to have regular intercourse with the intent of conception during the study. The primary outcome was live birth during the treatment period. Results: Women who received letrozole had more cumulative live births than those who received clomiphene (103 of 374 [27.5%] vs. 72 of 376 [19.1%], P=0.007; rate ratio for live birth, 1.44; 95% confidence interval, 1.10 to 1.87) without significant differences in overall congenital anomalies, though there were four major congenital anomalies in the letrozole group versus one in the clomiphene group (P=0.65). The cumulative ovulation rate was higher with letrozole than with clomiphene (834 of 1352 treatment cycles [61.7%] vs. 688 of 1425 treatment cycles [48.3%], P<0.001). There were no significant between-group differences in pregnancy loss (49 of 154 pregnancies in the letrozole group [31.8%] and 30 of 103 pregnancies in the clomiphene group [29.1%]) or twin pregnancy (3.4% and 7.4%, respectively). Clomiphene was associated with a higher incidence of hot flushes, and letrozole was associated with higher incidences of fatigue and dizziness. Rates of other adverse events were similar in the two treatment groups. Conclusions: As compared with clomiphene, letrozole was associated with higher live-birth and ovulation rates among infertile women with the polycystic ovary syndrome. (Funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development and others; ClinicalTrials.gov number, NCT00719186.).
    New England Journal of Medicine 07/2014; 371(2):119-129. DOI:10.1056/NEJMoa1313517 · 55.87 Impact Factor
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    ABSTRACT: Objective: Women with prior ectopic pregnancy (EP) have an increased failure rate when treated with single-dose methotrexate (MTX) for subsequent EP. We sought to determine whether previous EP remained a risk factor for failure when using the two-dose MTX protocol. Study design: Retrospective cohort study of women managed with two-dose MTX. Risk factors for MTX failure were evaluated in univariable analysis and multivariable regression modeling. Results: A total of 234 women with EP between 1999 and 2009 were studied. Of those, 37 (15.8%) had a prior EP. In univariable analysis, prior EP was associated with a greater than twofold increased risk of MTX failure (RR 2.67, 95% CI 1.20-3.77). Higher hCG levels and ultrasound visualization of EP also increased the risk of MTX failure. In multivariable analysis hCG level remained associated with MTX failure, while prior EP did not (adjusted RR 0.97, 95% CI 0.33-2.82). Conclusion: Prior EP is not independently associated with MTX failure in women receiving two-dose MTX therapy after controlling for known risk factors.
    The Journal of reproductive medicine 07/2014; 59(7-8):379-84. · 0.70 Impact Factor
  • Kurt T. Barnhart
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    ABSTRACT: The rationale to freeze all embryos to avoid transfer into a supraphysiologic environment to improve safety and efficacy is compelling, but not yet proven. How do we decide?
    Fertility and Sterility 07/2014; 102(1). DOI:10.1016/j.fertnstert.2014.05.024 · 4.59 Impact Factor
  • J. Zee · M. D. Sammel · K. Chung · P. Takacs · T. Bourne · K.T. Barnhart
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    ABSTRACT: Women who present with first-trimester vaginal bleeding often undergo evaluation for ectopic pregnancy (EP). After a confirmatory pregnancy test, women who show no ultrasound evidence of an intrauterine pregnancy or an EP are said to have a pregnancy of unknown location (PUL). It is estimated that 7% to 20% of women who initially have a PUL will have a final diagnosis of EP. Practitioners evaluating a PUL often face a difficult management decision: premature intervention can result in termination of a viable pregnancy, but delayed intervention may lead to rupture of an untreated EP. In women with a PUL, 2 serial human chorionic gonadotrophin (hCG) measurements within the first 48 hours after initial presentation are commonly used to help predict the final diagnosis. Because initial outcome predictions based on 2 hCG values are often incorrect, many practitioners have patients with a PUL return 2 to 5 days after the second hCG measurement for an additional hCG evaluation. At present, there is no standard of care regarding time and frequency of hCG testing in women with a PUL. The aim of this retrospective multicenter cohort study was to determine whether additional hCG values beyond the first 48 hours can improve diagnostic accuracy in women with a PUL. A total of 646 women with a PUL were recruited over 2 years at 3 academic centers in the United States; 146 of these women were ultimately diagnosed with EP. Participants presented to the emergency room with pain or bleeding in the first trimester, had a PUL on ultrasound, at least 2 hCG values, and a definitive final diagnosis after follow-up. Using standard clinical prediction rules, addition of a third hCG evaluation on day 4 after initial presentation significantly improved the accuracy of initial prediction from the first 2 hCG values by 9.3% (P = 0.015). Similarly, adding a third value on day 7 significantly improved the predicted diagnosis by 6.7% (P = 0.031). Assessing 4 hCG values (days 0, 2, 4, and 7) compared with 3 values (days 0, 2, and 4) produced a small insignificant improvement (1.3%) in the predicted diagnosis. The data show that measurement of hCG values 48 hours (2 days) apart does not optimize the accuracy of diagnosis in women with a PUL. Adding a third hCG measurement on day 4 or 7 significantly improves the predicted diagnosis for 1 in 15 women. Although these data provide useful information for the prediction of outcomes for women with a symptomatic first-trimester PUL, the results may not be generalizable to all pregnant women.
    Obstetrical and Gynecological Survey 07/2014; 69(7):399-400. DOI:10.1097/01.ogx.0000452704.04922.42 · 1.86 Impact Factor
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    ABSTRACT: Antithrombin (AT) is a 65 kDa glycoprotein belonging to a group of inhibitory factors known as serpins (serine protease inhibitors). It plays a critical role in the inhibition of coagulation and inflammation processes within the environment of the vascular endothelium. Inadequate levels of functional AT in plasma results in an increased risk of thrombotic events, both venous and arterial. AT deficiency can be inherited or acquired. Congenital AT deficiency is the most severe inherited thrombophilic condition with an odds ratio of 20 for the increased risk of venous thrombosis. Acquired AT deficiency occurs in a variety of physiologic and pathologic medical conditions with similar risks of increased thrombosis. In this article, we review clinical settings characterized by an acquired AT deficiency largely or partly subsequent to protein microvascular leakage. Other different mechanisms of AT depletion are implied in some clinical conditions together with endothelial loss, and, therefore, outlined. In addition, we provide a description of the current knowledge on the specific mechanisms underlying endothelial AT leakage and on the consequences of this protein decrease, specifically looking at thrombosis. We identify potential directions of research that might prove useful in patients with acquired AT deficiency.
    Thrombosis Research 06/2014; 133(6). DOI:10.1016/j.thromres.2014.02.014 · 2.45 Impact Factor
  • Kurt T Barnhart
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    ABSTRACT: Well-designed and -conducted clinical trials are needed to further advance the field for reproductive medicine. However, current reporting of outcomes of trials is ambiguous and disparate. In this review it is offered that the preferred outcome for clinical trials in reproductive medicine should be live birth. Multiple births should be listed, and it should be specified whether this is multiple births per couple or multiple births per conception. The unit of measure should be women (or couples) and not cycles. The duration of exposure should also be clearly identified (i.e., treatment was one cycle, a prespecified number of cycles, or a period of time). Pregnancy loss should be specified, and the denominator should be those who conceived. Although live birth is the primary outcome, complications should be defined and reported, including multiple births and other objective markers, such as preterm delivery, small-for-gestational age, or stillbirth.
    Fertility and sterility 05/2014; 101(5):1205-1208. DOI:10.1016/j.fertnstert.2014.03.026 · 4.59 Impact Factor
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    ABSTRACT: Tubal ectopic pregnancy can be surgically treated by salpingectomy, in which the affected Fallopian tube is removed, or salpingotomy, in which the tube is preserved. Despite potentially increased risks of persistent trophoblast and repeat ectopic pregnancy, salpingotomy is often preferred over salpingectomy because the preservation of both tubes is assumed to offer favourable fertility prospects, although little evidence exists to support this assumption. We aimed to assess whether salpingotomy would improve rates of ongoing pregnancy by natural conception compared with salpingectomy.
    The Lancet 02/2014; DOI:10.1016/S0140-6736(14)60123-9 · 45.22 Impact Factor
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    ABSTRACT: Objective To summarize baseline characteristics from a large multicenter infertility clinical trial. Design Cross-sectional baseline data from a double-blind randomized trial of two treatment regimens (letrozole vs. clomiphene). Setting Academic Health Centers throughout the United States. Patient(s) Seven hundred fifty women with polycystic ovary syndrome (PCOS) and their male partners took part in the study. Intervention(s) None. Main Outcome Measure(s) Historic, biometric, biochemical, and questionnaire parameters. Result(s) Females averaged 30 years and were obese (body mass index [BMI] 35) with ∼20% from a racial/ethnic minority. Most (87%) were hirsute and nulligravid (63%). Most of the women had an elevated antral follicle count and enlarged ovarian volume on ultrasound. Women had elevated mean circulating androgens, LH-to-FSH ratio (∼2), and antimüllerian hormone levels (8.0 ng/mL). In addition, women had evidence for metabolic dysfunction with elevated mean fasting insulin and dyslipidemia. Increasing obesity was associated with decreased LH-to-FSH levels, antimüllerian hormone levels, and antral follicle counts but increasing cardiovascular risk factors, including prevalence of the metabolic syndrome. Men were obese (BMI 30) and had normal mean semen parameters. Conclusion(s) The treatment groups were well matched at baseline. Obesity exacerbates select female reproductive and most metabolic parameters. We have also established a database and sample repository that will eventually be accessible to investigators. Clinical Trial Registration Number NCT00719186.
    Fertility and Sterility 01/2014; 101(1):258–269.e8. DOI:10.1016/j.fertnstert.2013.08.056 · 4.59 Impact Factor
  • J Zee · M D Sammel · K Chung · P Takacs · T Bourne · K T Barnhart
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    ABSTRACT: Are there improvements in the accuracy of prediction of ectopic pregnancy (EP) in women with early symptomatic pregnancy using human chorionic gonadotrophin (hCG) curves when clinicians consider visits beyond the first 48 h after initial presentation? Two hCG values, measured 48 h (2 days) apart, are often not sufficient to accurately predict the outcome of a woman with a pregnancy of unknown location (PUL), but adding a third visit on Day 4 or 7 significantly improved the prediction for 1 in 15 women. The use of serial hCG values is commonly used to aid in the prediction of the final diagnosis in women with a PUL. Initial outcome predictions based on two hCG values may often be incorrect. This retrospective multicenter cohort study included 646 women with a PUL, recruited over 2 years. Of these women, 146 were ultimately diagnosed with EP. Women presenting to the emergency room with first trimester pain or bleeding, with a PUL, at least 2 hCG values and a definitive final diagnosis from the University of Pennsylvania, University of Miami and University of Southern California, were recruited from 2007 to 2009. Using currently recommended prediction rules, adding a third hCG evaluation on Day 4 after initial presentation significantly improved the accuracy of initial prediction from the first two values (48 h apart, or Day 2) by 9.3% (P = 0.015). Adding a third value on Day 7 improved prediction significantly by 6.7% (P = 0.031), compared with prediction based on first two values. The improvement in prediction by assessing four hCG values (Days 0, 2, 4 and 7) compared with three values (Days 0, 2 and 4) was 1.3% and not statistically significant. Missing data imputation likely biased results toward the null; predicted outcomes may not match those made by clinicians; and the study does not predict intrauterine pregnancy and spontaneous miscarriage separately. This study provides useful information for the prediction of outcomes for women with a symptomatic first trimester pregnancy of unknown location, but may not be generalizable to all pregnant women. Supported by NIH grant numbers R01-HD036455 to Dr Barnhart and Dr Sammel, K24HD060687 to Dr Barnhart, and 5T32MH065218 to Ms. Zee. The authors have no conflicts of interest to declare.
    Human Reproduction 12/2013; 29(3). DOI:10.1093/humrep/det450 · 4.57 Impact Factor

Publication Stats

5k Citations
1,647.51 Total Impact Points


  • 1997–2015
    • University of Pennsylvania
      • • Perelman School of Medicine
      • • Department of Obstetrics and Gynecology
      • • Center for Clinical Epidemiology and Biostatistics
      • • Center for Research on Reproduction and Women's Health
      • • Department of Medicine
      Filadelfia, Pennsylvania, United States
  • 1995–2015
    • Hospital of the University of Pennsylvania
      • Department of Obstetrics and Gynecology
      Filadelfia, Pennsylvania, United States
  • 2014
    • Heilongjiang University of Chinese Medicine
      Charbin, Heilongjiang Sheng, China
  • 2003–2014
    • William Penn University
      Filadelfia, Pennsylvania, United States
  • 2005–2013
    • University of Miami
      • Department of Obstetrics and Gynecology
      كورال غيبلز، فلوريدا, Florida, United States
    • University of Pittsburgh
      Pittsburgh, Pennsylvania, United States
  • 2012
    • Center for Assisted Reproduction
      Бедфорд, Texas, United States
  • 2011
    • Wistar Institute
      • Center for Systems and Computational Biology (CSCB)
      Philadelphia, PA, United States
  • 2009
    • University of Innsbruck
      Innsbruck, Tyrol, Austria
  • 2008
    • Boston University
      Boston, Massachusetts, United States
  • 2004–2007
    • Columbia University
      • Department of Obstetrics and Gynecology
      New York, New York, United States
    • University of Rochester
      Rochester, New York, United States
    • University of Louisville
      Louisville, Kentucky, United States
  • 2004–2005
    • The Children's Hospital of Philadelphia
      • Department of Pediatrics
      Filadelfia, Pennsylvania, United States
  • 2002
    • Philadelphia University
      Filadelfia, Pennsylvania, United States
    • Pennsylvania Medical Society
      Filadelfia, Pennsylvania, United States
  • 2001
    • University of California, San Francisco
      San Francisco, California, United States
  • 1999
    • Virginia Commonwealth University
      • Division of Endocrinology and Metabolism
      Ричмонд, Virginia, United States