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1.
Ultrasound Obstet Gynecol ; 56(4): 611-617, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32349167

RESUMEN

OBJECTIVES: The objectives of this study were (1) to assess the prevalence of ultrasound (US) features of adenomyosis in an infertile population undergoing in-vitro fertilization (IVF), (2) to define the inter- and intrarater agreement of three-dimensional (3D) US assessment of adenomyosis, and (3) to evaluate sonographic features of adenomyosis with respect to pregnancy outcome following transfer of a single thawed euploid blastocyst. METHODS: This was a prospective cohort study. Subjects scheduled to undergo a single thawed euploid blastocyst transfer between April and December 2017 at a large IVF center were eligible for inclusion. Enrolled subjects underwent endometrial preparation for frozen embryo transfer. 3D-US was performed on the day prior to embryo transfer, with images stored for subsequent evaluation. Subjects then underwent transfer of a single thawed euploid blastocyst, and pregnancy outcomes were collected. All 3D-US volumes were de-identified and reviewed independently by five reproductive endocrinologists/infertility specialists with expertise in gynecological US for the presence of seven sonographic features of adenomyosis: global uterine enlargement, myometrial wall asymmetry, heterogeneous echogenicity, irregular junctional zone, myometrial cysts, fan-shaped shadowing and ill-defined myometrial lesions. Adenomyosis was considered to be present if the majority of the reviewers noted at least one of the seven sonographic features. Inter- and intrarater agreement was evaluated using Fleiss's kappa. Clinical and cycle characteristics of subjects with and those without adenomyosis were compared. The primary outcome of interest was live birth rate. Secondary outcomes included clinical pregnancy rate and miscarriage rate. Logistic regression analysis was performed to account for potential confounders. RESULTS: A total of 648 subjects were included. The prevalence of adenomyosis on US was 15.3% (99/648). On retrospective chart review, very few patients with adenomyosis had symptoms. The inter- and intrarater agreement amongst five independent specialists conducting the 3D-US assessments of adenomyosis were poor (κ = 0.23) and moderate (κ = 0.58), respectively. Subjects with adenomyosis were older (37.1 vs 35.9 years, P = 0.02) and more likely to undergo a gonadotropin-releasing hormone agonist downregulation protocol when compared with those without adenomyosis (12.1% vs 5.1%, P = 0.02). Clinical pregnancy (80.0% vs 75.0%) and live birth (69.5% vs 66.5%) rates were similar between the groups. When adjusting for potential confounders, there was no difference in the rate of clinical pregnancy (adjusted odds ratio (aOR), 1.47 (95% CI, 0.85-2.56)), miscarriage (aOR, 1.3 (95% CI, 0.62-2.72)) or live birth (aOR, 1.28 (95% CI, 0.78-2.08)) between subjects with and those without adenomyosis. No individual sonographic marker of adenomyosis was predictive of pregnancy outcome. CONCLUSIONS: The inter-rater agreement of 3D-US assessment of adenomyosis is poor. Furthermore, sonographic markers of adenomyosis in asymptomatic patients may not be associated with altered pregnancy outcome following transfer of a single thawed euploid blastocyst. These findings suggest that routine screening for asymptomatic adenomyosis in an unselected infertile patient population undergoing frozen embryo transfer may not be warranted. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Adenomiosis/diagnóstico por imagen , Transferencia de Embrión/efectos adversos , Imagenología Tridimensional , Resultado del Embarazo/epidemiología , Ultrasonografía/métodos , Aborto Espontáneo/epidemiología , Aborto Espontáneo/etiología , Adenomiosis/epidemiología , Adenomiosis/fisiopatología , Adulto , Tasa de Natalidad , Transferencia de Embrión/métodos , Femenino , Fertilización In Vitro , Humanos , Infertilidad/complicaciones , Nacimiento Vivo , Modelos Logísticos , Embarazo , Índice de Embarazo , Prevalencia , Estudios Prospectivos , Estudios Retrospectivos
3.
Hum Reprod ; 34(9): 1632-1639, 2019 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-31402381

RESUMEN

STUDY QUESTION: Does the reproductive potential of embryos change when blastocyst development takes longer than the traditionally accepted 5 days when accounting for aneuploidy and endometrial-embryo asynchrony? SUMMARY ANSWER: Aneuploidy increases with increasing duration of blastulation, but if blastocyst morphologic quality and endometrial-embryo asynchrony are controlled for, euploid Day 7 embryos have similar sustained implantation as compared to Days 5 and 6 euploid blastocysts. WHAT IS KNOWN ALREADY: The relative contributions of diminished embryo quality versus endometrial and embryo asynchrony to poor outcomes associated with embryos cultured past Day 6 are not clear. Asynchrony can be eliminated by embryo vitrification with transfer in a subsequent month after retrieval. STUDY DESIGN, SIZE, DURATION: Retrospective cohort study of patients from a single center attempting conception through ICSI and utilizing preimplantation genetic testing for aneuploidy screening (PGT-A) from January 2017 to September 2018. Cycles were excluded if they utilized surgical sperm or preimplantation genetic testing for monogenetic/single gene defects. ICSI cycle outcomes from 2586 patients were evaluated for ploidy status of embryos. PARTICIPANTS/MATERIALS, SETTING, METHODS: Only patients undergoing single, euploid frozen embryo transfer were included when analyzing cycle outcomes by day of blastocyst expansion of the transferred embryo (n = 2130). Ploidy rates by the day upon which an embryo was considered to be usable (denoted, 'usable blastulation day') were determined so as to assess the contribution of aneuploidy to slow embryo development. Outcomes of euploid frozen single embryo transfers (SET) of Day 7 embryos were evaluated to assess the reproductive potential associated with embryos that were slowly developing for reasons other than aneuploidy. Analyses were adjusted by maternal age and blastocyst morphology. MAIN RESULTS AND THE ROLE OF CHANCE: Overall, 67.7% (n = 3508) of usable Day 5 blastocysts were euploid, 52.1% (n = 5560) of usable Day 6 blastocysts were euploid and 43.1% (n = 229) of usable Day 7 embryos were euploid (Day 5 versus Day 6: odds ratio (OR) 0.7 (95% CI, 0.64-0.76), P < 0.001; Day 5 versus Day 7: OR 0.56 (95% CI, 0.46-0.69), P < 0.001; Day 6 versus Day 7: OR 0.81 (95% CI, 0.67-0.99), P = 0.036). Stratified by Society for Assisted Reproductive Technology maternal age groups, a reduction in the prevalence of euploidy by increasing time to embryo blastulation was still seen. The sustained implantation rate (SIR) was similar after euploid SET of Days 5 and 6 embryos (overall, 68.9% (95% CI, 66.0-71.6) and 66.8% (95% CI, 63.8-69.7), respectively; P = 0.81). SIR after euploid Day 7 SET appeared slightly lower than that of Days 5 and 6 embryos (52.6% (95% CI, 35.8-69.0); (Day 5 versus Day 7: OR, 0.67 (95% CI, 0.32-1.41), P = 0.29; Day 6 versus Day 7: OR 0.58 (95% CI, 0.28-1.2), P = 0.14)) but did not achieve statistical significance. LIMITATIONS, REASONS FOR CAUTION: The primary limitation is the low number of Day 7 blastocyst transfers that limits statistical power. Additionally, the retrospective nature of this study may prevent full elucidation of potential biases with respect to culture, morphologic assessment and selection of Day 7 embryos for transfer. WIDER IMPLICATIONS OF THE FINDINGS: Routine culture through Day 7 may successfully increase the pool of transferrable embryos for patients who would otherwise have no usable embryos if culture terminated on Day 6. This is particularly true for older patients (i.e. greater than 35 years of age), whose embryos take longer to blastulate and, therefore, are more susceptible to cycle cancelation. Additionally, as evidenced by an adequate overall SIR of 52.6% after euploid SET of Day 7 blastocysts, embryos developing to a usable blastocyst on Day 7 are likely within the 'window of blastulation.' STUDY FUNDING/COMPETING INTEREST(S): None.


Asunto(s)
Aneuploidia , Técnicas de Cultivo de Embriones/métodos , Implantación del Embrión/fisiología , Transferencia de un Solo Embrión/métodos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Adulto , Blastocisto , Criopreservación , Femenino , Pruebas Genéticas , Humanos , Embarazo , Índice de Embarazo , Diagnóstico Preimplantación/métodos , Estudios Retrospectivos , Factores de Tiempo
4.
Hum Reprod ; 33(8): 1489-1498, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30010882

RESUMEN

STUDY QUESTION: Do infertile women aged <38 years with quantitative evidence of diminished ovarian reserve and/or poor response to stimulation also exhibit poor oocyte quality as measured by blastulation rates, aneuploidy rates, and live birth rates? SUMMARY ANSWER: Young women with evidence of accelerated follicular depletion, either by precycle ovarian reserve testing or postcycle evidence of low oocyte yield, exhibit equivalent blastulation rates, aneuploidy rates and live birth rates per euploid embryo transfer as age-matched controls with normal precycle and postcycle parameters. WHAT IS KNOWN ALREADY: Previous studies are conflicted as to whether women with evidence of diminished ovarian reserve and/or poor ovarian response are also at increased risk of exhibiting evidence of poor oocyte quality. Most prior studies have failed to adequately control for the confounding effect of female age on typical markers of oocyte quality in poor responders. The rate of follicular depletion occurs at around 38 years on average; thus, evidence of quantitative depletion before this would indicate a premature diminution of ovarian reserve and allow evaluation of whether markers of oocyte quality are tied to quantitative markers. STUDY DESIGN, SIZE, DURATION: This was a retrospective cohort study at a single center between 2012 and 2016. This time frame was specifically chosen as all embryos were cultured to the blastocyst stage at this center during the study period (no cleavage stage transfers were performed). Two comparisons were made: precycle assessment of ovarian reserve (based on anti-mullerian hormone (AMH) level) and postcycle oocyte yield results. For each comparison, patients in <10th percentile were compared to patients in the interquartile range (IQR) with respect to blastulation rate, aneuploidy rate and live birth rate. A mixed effects model was created to control for female age (in the <38 year old range) and correlation among oocytes from a given cohort. PARTICIPANTS/MATERIALS, SETTING, METHODS: For the precycle blastulation analysis, only patients with AMH data available were included (345 patients with AMH in the <10th percentile versus 1758 patients with AMH in the 25th to 75th percentile (IQR)). To compare aneuploidy rates, the subset of these patients who pursued preimplantation genetic testing for aneuploidy (PGT-A) was then analyzed (124 patients in the <10th percentile versus 782 patients in the IQR). For the postcycle blastulation analysis, all patients who proceeded to retrieval (whether or not they also had AMH data available) were included (535 patients with oocyte yield in the <10th percentile versus 2675 patients in the IQR). To compare aneuploidy rates, the subset of these patients who pursued PGT-A was then analyzed (156 patients in the <10th percentile versus 1100 patients in the IQR). MAIN RESULTS AND THE ROLE OF CHANCE: The adjusted odds of a given fertilized oocyte developing to a blastocyst, being aneuploid or leading to a live birth after euploid transfer were no different if the oocyte was retrieved from a cycle with ovarian reserve parameters or oocyte yield in the <10th percentile compared to an oocyte retrieved in a cycle with those parameters in the 25-75th percentile. An AMH level in the <10th percentile did more commonly result in cycle cancellation prior to retrieval and after retrieval prior to transfer due to global arrest of embryos. LIMITATIONS, REASONS FOR CAUTION: The timing of retrieval in patients with fewer oocytes may be more optimal given the greater ability to discern the overall maturity of the cohort, thus enhancing performance per retrieved oocyte. Analyses included only first cycles. Subsequent adjustment of protocol due to prior performance may mean that some patients in the <10th percentile for oocyte yield are actually better prognosis patients than their first cycle indicates. Data on whether or not patients were on oral contraceptives at time that AMH level drawn was not available. Other unknown biases are also likely to be present given retrospective nature of the study. WIDER IMPLICATIONS OF THE FINDINGS: While young women with evidence of quantitative depletion of ovarian reserve have lower live birth rates per stimulation cycle, this not attributable to poor oocyte quality because the blastulation rate per fertilized oocyte and live birth rate per embryo transfer are equivalent to that in women with normal quantitative markers of ovarian reserve. Thus, the pathophysiology mediating a premature quantitative decline in ovarian reserve appears different than that which mediates markers of oocyte quality, such as aneuploidy. Young poor responders may use this information to help guide embryo accumulation strategies when considering their family building plans. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Fármacos para la Fertilidad Femenina/uso terapéutico , Infertilidad Femenina/terapia , Reserva Ovárica , Ovario/efectos de los fármacos , Inducción de la Ovulación , Ovulación/efectos de los fármacos , Adulto , Factores de Edad , Aneuploidia , Blastómeros/patología , Bases de Datos Factuales , Técnicas de Cultivo de Embriones , Transferencia de Embrión , Femenino , Fertilización In Vitro , Humanos , Infertilidad Femenina/diagnóstico , Infertilidad Femenina/fisiopatología , Nacimiento Vivo , Ovario/fisiopatología , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Resultado del Tratamiento
5.
Artículo en Inglés | MEDLINE | ID: mdl-11570764

RESUMEN

ZnO thin films with a high piezoelectric coupling coefficient are widely used for high frequency and low loss surface acoustic wave (SAW) devices when the film is deposited on top of a high acoustic velocity substrate, such as diamond or sapphire. The performance of these devices is critically dependent on the quality of the ZnO films as well as of the interface between ZnO and the substrate. In this paper, we report the studies on piezoelectric properties of epitaxial (1120) ZnO thin films grown on R-plane sapphire substrates using metal organic chemical vapor deposition (MOCVD) technique. The c-axis of the ZnO film is in-plane. The ZnO/R-Al2O3 interface is atomically sharp. SAW delay lines, aligned parallel to the c-axis, were used to characterize the surface wave velocity, coupling coefficient, and temperature coefficient of frequency as functions of film thickness to wavelength ratio (h/lambda). The acoustic wave properties of the material system were calculated using Adler's matrix method, and the devices were simulated using the quasi-static approximation based on Green's function analysis.

6.
IEEE Trans Biomed Eng ; 46(10): 1253-60, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10513131

RESUMEN

Prostate malignancies are the second leading cause of cancer deaths among men. The most common method of detecting this disease is digital rectal examination (DRE). Current DRE training is inadequate, since the number of patients that students can practice on is limited. Furthermore, allied care personnel do not train in screening for prostate cancer. Finally, there is no objective way to follow the improvement in DRE skills for medical personnel. This paper presents a virtual reality-based simulator that addresses the above problems. The prototype consists of a PHANToM haptic interface which provides feedback to the trainee's index finger, a motion restricting board, and an SGI workstation, which renders the patient's anatomy. Four types of prostates were modeled--normal, enlarged with no tumor, incipient malignancy (single tumor), and advanced malignancy (tumor cluster). Human factors studies were conducted on both nonmedical students and urology residents in order to quantify the system usefulness. After only five minutes of training, nonmedical students had a 67% correct diagnosis rate of malignant versus nonmalignant cases. This compared with 56% for urology residents in the same trials. Subjective evaluation by the residents pointed out the need to improve the virtual prostate model realism. A control group formed of urology residents performed the same trials on a modified Merck Procar simulator. The control group scored significantly better (96% correct diagnosis of malignancies). We conclude that the virtual prostate palpation simulator, while promising, needs significant improvement in both model realism and haptic interface hardware.


Asunto(s)
Instrucción por Computador , Diagnóstico por Computador , Internado y Residencia , Neoplasias de la Próstata/diagnóstico , Urología/educación , Interfaz Usuario-Computador , Simulación por Computador , Femenino , Humanos , Masculino , Modelos Anatómicos , New Jersey , Palpación/métodos
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