2004 Annual Meeting
ABSTRACT 1
Fetal Cheek-to-Cheek Diameter in the Prediction of Mode of DeliveryBy Invitation
Jacques S. Abramowicz, M.D.
Sarosh Rana, M.D.
Shelly Abramowicz, D.M.D., M.P.H.
OBJECTIVE: To assess sonographic fetal cheek-to-cheek diameter (CCD) in predicting mode of delivery.
STUDY DESIGN: Two hundred sixty four patients were considered in 2 parts. First, a retrospective analysis of 214 patients entered into a birth weight (BW) study. Measurements of the CCD, biparietal diameter (BPD) and BW as well as labor data were collected. Then a prospective study of patients at ≥38 weeks gestational age. Fetal weight (EFW) was estimated by routine measurements. Information regarding CCD was withheld from the delivering caregiver. Labor records were reviewed for BW and complications, defined as: instrumental delivery, cesarean section (C/S) for non-progress of labor or "CPD" and "difficult" vaginal delivery. The CCD, BW (both parts) or EFW (prospective part) and mode of delivery were compared.
RESULTS: Abnormal CCD (>2SD above norms) was closely associated with cesarean delivery, regardless of EFW. At term, risk of C/S with a CCD >7.9cm. was 94%.
CONCLUSION: Within limits, EFW alone has weak correlation with cesarean delivery. CCD, as a reflector of fetal adipose tissue, performs as well as actual BW and demonstrates good prediction for delivery by C/S.
DISCUSSANT: Richard L. Berkowitz, M.D.
ABSTRACT 2
The Role of Ultrasound in the Detection of Early Stage Epithelial Ovarian CarcinomaBy Invitation
David A. Fishman, M.D.
Leeber Cohen, M.D.
Diljeet Singh, M.D., M.P.H.
Kenny Bozorgi, M.D.
Ralph Tamura, M.D.
John R. Lurain, M.D.
Peter E. Schwartz, M.D.
CONTEXT: Epithelial ovarian cancer (EOC) kills more women than all other gynecologic malignancies combined due to our inability to detect early stage disease. Ultrasonography has demonstrated utility in detecting ovarian cancer in asymptomatic women, but its value for the detection of early stage EOC in women at increased risk is uncertain.
OBJECTIVE: To examine the utility of sonography in detecting early stage EOC in asymptomatic high-risk women participating in the National Ovarian Cancer Early Detection Program (NOCEDP).
DESIGN, SETTING, AND PARTICIPANTS: Only asymptomatic women deemed at increased risk for developing ovarian cancer with normal gynecologic and ultrasound examinations were eligible to participate in our IRB approved NOCEDP. Participants undergo comprehensive gynecologic and ultrasound examinations every 6 months. Increased risk includes women with at least one affected first degree relative with ovarian cancer; a personal history of breast, ovarian, or colon cancer; one or more affected first and second degree relatives with breast and or ovarian cancer; inheritance of a BRCA mutation from an affected family member; or membership within a recognized cancer syndrome.
RESULTS: 4,526 women were evaluated with an average age of 46 years. 2,610 women were premenopausal and 1,916 postmenopausal. A total of 12,709 scans were performed. Visualization of both ovaries was noted in 98% of premenopausal and in 94% of postmenopausal women. 14 women had a prior unilateral salpingooophorectomy. Recall rates at less than the routine 6-month interval were 0.4% in the premenopausal and 0.3% in postmenopausal women. A total of 98 women with persistent adnexal masses were identified and 48 invasive surgical procedures were performed diagnosing 37 benign ovarian tumors and 11 gynecologic malignancies. All cancers were detected in asymptomatic women who had normal US and physical examinations 12 and 6 months prior to cancer diagnosis. The detected malignancies were fallopian tube carcinoma (4)- stage IIIC, primary peritoneal carcinoma (3)- one Stage IIIA, one- Stage IIIB, one Stage IIIC, epithelial ovarian carcinoma (2)- Stage IIIA and IIIB, and endometrial adenocarcinoma (2)- Stage IA. Additionally 27 primary and 7 recurrent breast carcinomas were detected by physical examination. A total of 184 women with genetic predisposition (BRCA+) have had a prophylactic bilateral salpingo- oophorectomy (BSO), 23% demonstrating atypical hyperplasia, and unexpectedly two women (1%) were found to have Stage III (A and B) primary peritoneal carcinoma.
CONCLUSIONS: This study demonstrates the limited value of diagnostic ultrasound as an independent modality for the detection of early stage epithelial ovarian cancer in asymptomatic increased risk women.
DISCUSSANT: John R. Van Nagell, M.D.
ABSTRACT 3
Obstetrical Outcomes in Women with 2 Prior Cesareans: Is VBAC a Viable Option?By Invitation
George A. Macones, M.D., M.S.C.E.
Alison Cahill, M.D.
Emmanuelle Pare, M.D.
David M. Stamilio, M.D.
Sarah Ratcliffe, Ph.D.
Erika Stevens, M.S.
Mary Sammel, Sc.D.
Jeffrey Peipert, M.D., M.P.H.
OBJECTIVE: To compare clinical outcomes in women with 1 vs. 2 prior cesareans who attempt VBAC and also to compare clinical outcomes of women with 2 prior cesareans who attempt VBAC or opt for a repeat cesarean delivery.
STUDY DESIGN: We performed a secondary analysis of a retrospective cohort study, in which the medical records of over 25,000 women with a prior cesarean from 16 community and tertiary care hospitals were reviewed by trained nurse abstractors. Information on demographics, obstetrical history, medical and social history, and the outcomes of the index pregnancy was obtained. Comparisons of obstetrical outcomes were made between women with 1 vs 2 prior cesareans, and also between women with 2 prior cesareans who opt for VBAC attempt vs elective repeat cesarean. Both bivariate and multivariate techniques were used for these comparisons.
RESULTS: The records of 20,175 women with one prior cesarean section and 3,970 with two prior cesarean sections were reviewed. The rate of VBAC success was similar in women with a single prior cesarean (75.5%) compared to those with 2 prior cesareans (74.6%), though the odds of major morbidity were higher in those with 2 prior cesareans (adjusted OR=1.61 95% CI 1.11-2.33). Among women with 2 prior cesareans, those who opt for a VBAC attempt had higher odds of major complications compared to those who opt for elective repeat cesarean (adjusted OR=2.26, 95%CI 1.17-4.37).
CONCLUSIONS: The likelihood of major complications is higher with a VBAC attempt in women with 2 prior cesareans compared to those with a single prior cesarean. In women with 2 prior cesareans, while major complications are increased in those who attempt VBAC relative to elective repeat cesarean, the absolute risk of major complications remains low.
DISCUSSANT: Jay D. Iams, M.D.
ABSTRACT 4
Benign Gynecologic Conditions Among Participants in the Breast Cancer Prevention TrialBy Invitation
Eva Chalas, M.D.
Joseph P. Costantino, Dr.P.H.
D. Lawrence Wickerham, M.D.
Norman Wolmark, M.D.
George C. Lewis, M.D.
Cynthia. Bergman, M.D.
Carolyn D. Runowicz, M.D.
OBJECTIVE: To report on the benign gynecologic conditions occurring among women with an intact uterus at enrollment in the Breast Cancer Prevention Trial of the National Surgical Adjuvant Breast and Bowel Project.
STUDY DESIGN: The incidence rates of several benign gynecologic conditions were determined and risks were compared among women receiving tamoxifen and those receiving placebo, based on risk ratios (RRs) with 95% confidence intervals. Comparisons included stratification by menopausal status, body mass index, and history of estrogen use.
RESULTS: Compared with women taking placebo, women taking tamoxifen had a greater incidence of endometrial polyps (RR = 1.9 for premenopausal women and RR = 2.4 for postmenopausal women), simple endometrial hyperplasia without atypia (overall RR = 2.06), leiomyomas (RR = 1.3 for premenopausal women and RR = 1.4 for postmenopausal women), endometriosis (RR =1.9 for premenopausal women and RR = 2.6 for postmenopausal women), ovarian cysts (RR = 1.5 for premenopausal women only), and gynecologic surgical procedures, including hysterectomy (RR = 1.6 for premenopausal women and 2.2 for postmenopausal women).
CONCLUSIONS: Our results strongly support the estrogen agonist role of tamoxifen as the causative factor for the increased risk of endometrial polyps, leiomyomas, endometriosis, and endometrial hyperplasia among women taking this agent.
DISCUSSANT: Benjamin E. Greer, M.D.
ABSTRACT 5
The Fibronectin Receptor α5 Integrin Subunit Is Up-Regulated by Cell-Cell Adhesion Via a Cyclic AMP-Dependent Mechanism: Implications for Human Trophoblast MigrationBy Invitation
Christos Coutifaris, M.D., Ph.D.
Akinyinka Omigbodun, M.D.
George Coukos, M.D., Ph.D.
Cell adhesion molecules are implicated in the mechanisms regulating trophoblast migration during human embryo implantation and placentation. We investigated the expression and subcellular organization of the fibronectin receptor α5 integrin subunit during the differentiation of human trophoblasts in vitro, and the role of cyclic AMP (cAMP) in the process. Human trophoblasts freshly isolated from chorionic villi expressed no α5 integrin, but the molecule was up-regulated as cells aggregated in vitro. Low levels of expression of α5 integrin subunit and a diffuse cellular distribution pattern was seen in migrating mononuclear trophoblasts. Formation of cell aggregates was accompanied by a dramatically increased expression of the α5 integrin, which translocated to the cytoskeleton-bound pool of proteins and clustered within focal adhesion plaques on the cell surface. This coincided with increased binding to fibronectin and decreased migratory activity. In the absence of cell-cell adhesion, trophoblasts did not display an increase in α5 integrin mRNA or protein and there was no α5 integrin in focal adhesion plaques, suggesting that cell-cell contacts specifically trigger the up-regulation of α5 integrin subunit and its subcellular translocation. Cyclic AMP is the second messenger mediating the aggregation-induced increase in α5 integrin: cAMP increased the de novo synthesis of α5 integrin protein, particularly in mononuclear cells, while the aggregation- induced increase in α5 integrin was strongly inhibited by the antagonist Rp-cAMP in aggregating cells. Our data provide evidence that the α5 integrin mediates binding of human trophoblasts to fibronectin and is implicated in the regulation of trophoblast migration. This integrin is specifically triggered by cell-cell adhesion and regulated via cAMP-mediated pathway(s). It is hypothesized that these mechanisms may play an important part in the molecular events controlling human placentation.
DISCUSSANT: Linda C. Giudice, M.D., Ph.D.
ABSTRACT 6
Telomere Length Predicts Embryo Fragmentation Following In Vitro Fertilization - Toward a Telomere Theory of Reproductive Aging in WomenBy Invitation
David L. Keefe, M.D.
Sonia Franco, Ph.D.
Lin Liu, Ph.D.
James R. Trimarchi, Ph.D.
Benning Cho, Ph.D.
Sherry Weitzen, Ph.D.
Shoba Agarwal, M.D.
Maria A. Blasco, M.D.
OBJECTIVES: Telomeres protect chromosome ends, facilitate chiasmata formation during meiosis, and shorten with cell division and exposure to reactive oxygen during aging. Oocytes and early embryos lack telomerase, fixing telomere length during early oogenesis. Telomere shortening in mice disrupts meiosis, reduces chiasmata, halts development and promotes apoptosis in embryos, mimicking reproductive senescence. Ethics limit destruction of human embryos, but fragmentation reflects apoptosis.
STUDY DESIGN: Observational study of telomere length in human eggs and fragmentation in embryos.
MATERIALS AND METHODS: To test the hypothesis that telomere shortening triggers apoptosis in human embryos, we evaluated telomere length as a predictor of fragmentation in human embryos after IVF.
RESULTS: Telomere length negatively predicted fragmentation in day three embryos, after controlling for age and FSH level. Telomere length did not predict other features of embryo morphology.
CONCLUSION: Telomere shortening may promote apoptosis in human embryos, consistent with a role for telomeres in reproductive senescence.
DISCUSSANT: Joe Leigh Simpson, M.D.
ABSTRACT 7
Correlation of Cyclooxygenase-2 (COX-2) and Aromatase Expression in Human Endometrial Cancer: Tissue Microarray AnalysisBy Invitation
Jeffrey M. Fowler, M.D.
Nilsa Ramirez, M.D.
David E. Cohn, M.D.
Nicole Kelbick, Ph.D.
Marshall Stepanian, M.D., Ph.D.
Inbar Ben-Shachar, M.D.
Carl Morrison M.D., D.V.M.
OBJECTIVE: The objective of this study was to compare the prevalence of COX-2, aromatase and hormone receptor status immunohistochemical (IHC) expression to well defined clinical-pathologic prognostic factors in a large group of surgically staged endometrial cancer patients.
STUDY DESIGN: Atissue microarray (TMA) was constructed from 336 separate specimens of endometrial cancer. IHC was performed for estrogen (ER) and progesterone (PR) receptor, COX-2, COX-1 and aromatase.
RESULTS: The majority of patients expressed COX-2 (59%) and aromatase (65%). COX-2 staining significantly correlated with aromatase expression but negative ER and PR. COX-2 expression was correlated with histologic grade (P<0.026) and approached statistical significance for deep myometrial invasion (P<0.055). After applying multivariate analysis, no single IHC or combination of IHC's correlated with intrauterine poor prognostic factors or advanced stage. Only myometrial invasion >50% (MI>50%) (O.R.=6.98, p<0.001) and non-endometroid histology (O.R.=4.933, p<0.001) were predictive of advanced stage after multivariate analysis.
CONCLUSION: COX-2 is an important factor in tumorigenesis, disease progression, angiogenesis and invasion. COX-2 and aromatase are expressed in the majority of endometrial cancer patients and may be associated with other poor prognostic factors. However, surgical staging remains critical to define prognosis and guide further therapy.
DISCUSSANT: Andrew Berchuck, M.D.
ABSTRACT 8
Screening Candidate Genes for Mutations in Patients with Hypogonadotropic Hypogonadism Using Custom Genome Resequencing MicroarraysBy Invitation
Lawrence C. Layman, M.D.
Ning Xu, M.B.
Robert H. Podolsky, Ph.D.
Pranav Chudgar, B.S.
Lynn P. Chorich, M.S.
Chunmei Liu, M.S.
Paul G. McDonough, M.D.
Janet A. Warrington, Ph.D.
OBJECTIVE: To determine the consistency of calling single nucleotide polymorphisms (SNPs) by custom genome resequencing microarrays compared with capillary DNA sequencing.
STUDY DESIGN: Amplified genomic DNA from 23 patients with hypogonadotropic hypogonadism was hybridized to microarrays containing 30 kilobases of sequence from six different candidate genes. Capillary DNA sequencing was performed in ten patients.
RESULTS: For 10 patients with ≥90% of bases called, 49 SNPs in 5 of 6 genes were identified. Of the 490 bases, 75 were read as "N" and 415 were able to be called. Of 415, 401 (96.6%) sequences were confirmed by DNA sequencing. All homozygotes (285/285) were called identically, while sequence from 89.2% (116/130) of heterozygotes agreed by both methods. The level of agreement between microarray calls and capillary DNA sequencing demonstrated substantial accuracy.
CONCLUSIONS: Custom genome resequencing microarrays are highly consistent with capillary sequencing in calling individual bases in genomic DNA from patients with human disease.
DISCUSSANT: Eli Y. Adashi, M.D.
ABSTRACT 9
RU-486 Inhibits Expression of Lysophosphatidic Acid Induced GlycodelinBy Invitation
Ana A. Murphy, M.D.
Sumathi Ramachandran, Ph.D.
MingQing Song, M.D., Ph.D.
Erin Lowe, B.A.
Celia E. Dominguez, M.D.
Sampath Parthasarathy, Ph. D.
OBJECTIVES: To show that histiocytes may be a source of glycodelin in leiomyoma. To provide evidence for the mode of action of RU486 on glycodelin produced by K562 cells, an in vitro model for leukocytes.
STUDY DESIGN: Immunocytochemistry for glycodelin and HAM- 56 (macrophage) was performed on leiomyoma and myometrium. Using K562 cells, the effect of LPA, RU486, antioxidants and ZK122,993 on glycodelin protein and gene expression was studied.
RESULTS: Histiocytes in leiomyoma and myometrium co-localize with glycodelin. Incubation of K562 cells with LPA, PMA and progesterone significantly induced the expression of glycodelin protein and mRNA. In unstimulated cells, ZK112,993 and RU486 express agonist activity and increase glycodelin. The addition of RU486, an antioxidant and antiprogestin, to LPA-activated cells markedly reduced expression of glycodelin. Addition of ZK112,993, an antiprogestin without antioxidant properties, to LPA-activated cells did not reduce glycodelin. RU486 significantly inhibited glycodelin expression in LPA activated cells.
CONCLUSIONS: Histiocytes in leiomyoma and myometrium immunostain for glycodelin and suggests a source for glycodelin in leiomyoma. In unstimulated K562 cells, RU486 and ZK112,993 exhibited progesterone agonist activity and increased glycodelin. RU486 markedly reduced glycodelin production in LPA-activated cells. These data suggest an antioxidant mechanism for RU486-mediated inhibition of glycodelin. The antioxidant properties of RU486 may be responsible for its antiangiogenic and antiproliferative properties.
DISCUSSANT: Robert N. Taylor, M.D., Ph.D.
ABSTRACT 10
Mechanotransduction Related to Acute Shortening Is Dependent on Prostaglandins in Myometrium from Pregnant WomenBy Invitation
William W. Hurd, M.D.
Shawn G. Gibbs, Ph.D.
Gary Ventolini, M.D.
Gary M. Horowitz, M.D.
Steven R. Guy, M.D.
OBJECTIVE(S): To determine if acute shortening alters spontaneous contractility in myometrial strips obtained from pregnant women.
METHODS: Isometric contractions were measured in myometrial strips obtained at cesarean delivery from 14 pregnant women at term. After 2 hours of stretching, the lengths of the strips were decreased to 96%, 94%, or 92% of the stretched strips. Spontaneous contractility was measured for 120 minutes in the absence or presence of indomethacin (10-5 M), and cumulative concentration response curves to oxytocin determined.
RESULTS: Contractility was increased by 29% and 34% in strips shortened to 96% and 94%, respectively. Preincubation with indomethacin increased contractility by 15% in 100% strips, and decreased contractility by 30% and 19% in 96% and 94% strips, respectively. Contraction frequency was increased by 26% and 53% for the strips shortened to 94% and 92%, respectively, and these increases were prevented by indomethacin. The responses to oxytocin were similar at all lengths.
CONCLUSION(S): Sustained myometrial stretching decreases and acute shortening increases spontaneous contractility by a mechanism involving prostaglandins.
DISCUSSANT: Mark Phillippe, M.D.
ABSTRACT 11
Metabolites of Progesterone and the Pregnane X Receptor: A Novel Potential Pathway Regulating Uterine Contractility in PregnancyBy Invitation
Bryan F. Mitchell, M.D., M.S.C.E.
OBJECTIVE: To determine the role of metabolites of progesterone (as represented by 5β-dihydroprogesterone, 5β-DHP), acting through the nuclear receptor PXR, in regulating uterine contractility.
STUDY DESIGN: Studies were performed using non-pregnant and pregnant wild type and PXR knockout mice. RT-PCR, enzyme assays, immunofluorescence microscopy, western analyses and a muscle bath apparatus were used to investigate the effects of acute and chronic treatment with 5β-DHP.
RESULTS: Uterine tissues from several species contain 5β-reductase activity and also express the gene for PXR at the level of mRNA and protein. Acute treatment with 5β-DHP causes rapid uterine relaxation that is not mediated by PXR. Chronic administration of 5β- DHP increases uterine expression of inducible nitric oxide synthase and causes changes that, in some respects, mimic changes observed in pregnancy.
CONCLUSIONS: These data support the hypothesis that metabolites of progesterone may act acutely through a non-genomic mechanism and genomically through PXR to regulate uterine contractility. Further studies are warranted to elucidate the role of this novel system in the maternal adaptation to pregnancy.
DISCUSSANT: Michael G. Ross, M.D., M.P.H.
ABSTRACT 12
The Effects of Progestins on Bone Density and Bone Metabolism in Postmenopausal Women: A Randomized Controlled TrialBy Invitation
James H. Liu, M.D.
Ken N. Muse, M.D., M.P.H.
OBJECTIVE: The purpose of this study is to evaluate the action of progestins on bone metabolism in early menopausal women.
STUDY DESIGN: 132 menopausal women were randomized into a two-year double-blinded, placebo-controlled clinical trial. There were 6 treatment groups: micronized progesterone (P4) 300 mg/day; medroxyprogesterone acetate (MPA) 10 mg/day; norethindrone (NET) 1 mg/day; micronized estradiol (E2) 1 mg/day; E2 1 mg/day + MPA 10 mg/day; and placebo. All subjects received 1000 mg of calcium and 400 IU of vitamin D/day. Primary outcome variables were bone mineral density (BMD) changes at the spine and hip. Secondary variables were bone turnover markers.
RESULTS: With E2 or E2+MPA treatment, BMD at L2-L4 increased by 2 to 4% over two years. BMD at the spine followed a decreasing trend with MPA, P4, and placebo treatments. With NET treatment, BMD did not change from baseline. At the femoral neck site, BMD did not change significantly for any treatment group. Bone resorption and bone formation markers decreased with E2 or E2+MPA treatment and did not change appreciably with all three progestinalone treatments. There were no vertebral or hip fractures observed during the trial.
CONCLUSIONS: Estrogen remains the primary bone active agent in hormone therapy while progestins have significantly less activity. The selection of the appropriate progestin in hormone therapy should be based on criteria other than bone activity.
DISCUSSANT: Rogerio A. Lobo, M.D.
ABSTRACT 13
The Epidemiology of Threatened Premature Labor - A Prospective Cohort StudyBy Invitation
John M. Thorp, Jr., M.D.
Melissa L. McPheeters, Ph.D., M.P.H.
William C. Miller, M.D., Ph.D., M.P.H.
Katherine Hartmann, M.D., Ph.D.
David A. Savitz, Ph.D.
Jay Kaufman, Ph.D.
Joanne M. Garrett, Ph.D.
OBJECTIVE: To describe the population of women who received a hospital-based diagnosis of preterm labor in a prospective cohort study, determine when they received their first preterm labor diagnosis (before or after 33 weeks gestation), and describe short and long-term pregnancy outcomes.
METHODS: The Pregnancy, Infection and Nutrition (PIN) study follows a cohort of pregnant women from three clinical sites with varied levels of risk for preterm birth to identify predictors of preterm birth. Administrative records from the relevant community hospital and university medical center were merged with data from 2534 women in the PIN study to identify hospital admissions for preterm labor. Factors considered to increase risk for preterm birth were examined for an association with any preterm labor diagnosis, a preterm labor diagnosis prior to 33 weeks gestation, or at 33 weeks gestation or later. Logistic regression was used to identify key associations with diagnosis in these gestational periods.
RESULTS: Nine percent (n=234) of the study population had one or more hospital-based episodes of care for preterm labor. In 38% of cases (n=90), delivery occurred during the first preterm labor hospitalization. Having had a prior preterm birth was the only factor consistently associated with a diagnosis of preterm labor ever during pregnancy, up to and including 32 weeks gestation and after 32 weeks gestation. Reporting having had a sexually transmitted infection or bacterial vaginosis early in pregnancy was associated with hospitalization for preterm labor between 24 weeks and 32 weeks gestation (OR 1.8: 95% CI 1.1 - 3.0 and OR 2.6; 95% CI: 1.7 - 4.1, respectively).
CONCLUSION: The incidence of first-time hospitalization for threatened preterm labor is 9%. Most of those episodes do not result in preterm birth. Prior preterm birth was a consistent risk factor for both women diagnosed with threatened preterm labor before and after 33 weeks gestation.
DISCUSSANT: Steve N. Caritis, M.D.
ABSTRACT 14
Assessment of Resident Surgical Skills: Is Testing Feasible?By Invitation
Barbara A. Goff, M.D.
Lynn Mandel, Ph.D.
Gretchen Lentz, M.D.
Amy VanBlaricom, M.D.
Anne-Marie Amies, M.D.
David Lee, M.D.
Andrew Galakatos, M.D.
Matthew Davies, M.D.
Peter Nielsen, M.D.
OBJECTIVE: We have previously shown that in a single residency program objective structured assessment of technical skills (OSATS) is a reliable and valid method of assessing surgical competency. Our goal was to establish feasibility of this evaluation instrument when administered at multiple residency programs throughout the United States and assess the impact of a laboratory based surgical curriculum on results.
METHODS: An OSATS exam was administered to 116 residents from five residency programs. One of the residency programs had participated in a comprehensive surgical curriculum over a fouryear period of time. The exam consisted of three open and three laparoscopic tasks. Residents were graded by both a blinded and unblinded examiner with task specific checklist, global rating scale, pass/fail assessment, and tasks were timed. All tasks were performed on lifelike models.
RESULTS: Examinations were successfully completed at all sites. Each exam required 90 minutes of resident time. Reliability indices calculated with Cronbach's a were .97 for overall global rating and .95 for checklists. lnterrater reliability between blinded and unblinded examiners ranged from .68 to .98 for individual tasks and was .94 overall. Assessment of construct validity (the ability to distinguish among residency levels) found significant differences among the residents for both blinded and unblinded examiners for all evaluation outcomes except time. For the test overall, the global rating scale had significant differences among all four residency levels. The checklist showed significant differences at three levels (PGY3-4 > PGY2, > PGY1). Approximate cost for replaceable items was $40-150 per resident depending on which tasks were chosen. Comparison of scores between residents who received a laboratory-based curriculum and those who did not revealed significantly higher scores and shorter time to complete tasks for the group who received additional training.
CONCLUSION: Large-scale testing has confirmed that OSATS are an objective, reliable and valid method to assess surgical competency and can easily be administered in most residency programs. A laboratory-based surgical curriculum improved test results and reduced time to complete tasks.
DISCUSSANT: Daniel L. Clarke-Pearson, M.D.
ABSTRACT 15
Is a Change in the Vaginal Flora Associated with an Increased
Risk of Preterm Birth?
By Invitation
J. Christopher Carey M.D.
Mark A. Klebanoff, M.D.
OBJECTIVE: To determine if a change in the vaginal flora was associated
with an increased risk of preterm birth and to determine if
metronidazole therapy prior to 32 weeks increased the risk of
preterm birth.
STUDY DESIGN: We compared cultures taken at 23-26 weeks of
gestation with cultures taken at delivery from women enrolled in
the Vaginal Infections and Preterm Birth study to analyze the association
of changes in the vaginal flora with preterm birth.
RESULTS: Metronidazole therapy prior to 32 weeks was associated
with an increased risk of preterm birth (OR 1.5, 95% CI 1.05-2.1) in
an unadjusted model. Achange to heavy growth of E. coli or K. pneumoniae at delivery was found to be associated with preterm birth
(OR 2.4, 95% CI 1.6-3.8). After controlling for race, parity, pre-pregnancy
weight <100 pounds, smoking or drinking during pregnancy, T. vaginalis, bacterial vaginosis, chlamydia, mycoplasmas, group B
streptococcus, metronidazole therapy prior to 32 weeks, vaginal pH
>5.0, and an increase in E. coli or K. pneumoniae, only prepregnancy
weight <100 pounds (adjusted odds ratio 2.07, 95% CI 1.01-4.21) and
increased E. coli or K. pneumoniae in the vagina at delivery (adjusted
odds ratio 2.99, 95% CI 1.37-6.53) were found to be significantly
associated with preterm birth.
CONCLUSIONS: An increase in E. coli or K. pneumoniae in the vagina
is an independent risk factor for preterm birth. Changes in the
vaginal flora may explain the increased risk of preterm birth seen
with vaginal clindamycin or oral metronidazole therapy.
DISCUSSANT: Robert L. Goldenberg, M.D.