Multicenter prospective study of concordance between embryonic cell-free DNA and trophectoderm biopsies from 1301 human blastocysts.

BACKGROUND: The recent identification of embryonic cell-free DNA in spent blastocyst media has opened a new era of possibilities for noninvasive embryo aneuploidy testing in assisted reproductive technologies. Yet, previous studies assessing a limited number of embryos reported variable concordance between embryonic cell-free DNA and trophectoderm biopsies, thus questioning the validity of this approach. OBJECTIVE: This study aimed to evaluate the concordance and reproducibility of testing embryonic cell-free DNA vs trophectoderm DNA obtained from the same embryo in a large sample of human blastocysts and to assess the contribution of the inner cell mass and trophectoderm to embryonic cell-free DNA released to the culture media. STUDY DESIGN: This is an interim analysis of a prospective, observational study among 8 in vitro fertilization centers in 4 continents to assess consistency between noninvasive embryo aneuploidy testing of embryonic cell-free DNA and conventional trophectoderm biopsy. The analysis included 1301 day-6/7 blastocysts obtained in 406 in vitro fertilization cycles from 371 patients aged 20-44 years undergoing preimplantation genetic testing for aneuploidy. Fresh oocytes underwent intracytoplasmic sperm injection or in vitro fertilization. No previous assisted hatching or vitrification was allowed before media collection. Individual spent blastocyst medium was collected from embryos cultured at least 40 hours from day 4. After media collection, conventional preimplantation genetic testing for aneuploidy, comprising trophectoderm biopsy and blastocyst vitrification, was performed. Embryonic cell-free DNA was analyzed blindly after embryo transfer. Inner cell mass and trophectoderm biopsies were also performed in a subset of 81 aneuploid blastocysts donated for research. RESULTS: Embryonic cell-free DNA analyses were 78.2% (866/1108) concordant with the corresponding trophectoderm biopsies. No significant differences were detected among centers ranging from 72.5% to 86.3%. Concordance rates exceeded 86% when all defined steps in the culture laboratory were controlled to minimize the impact of maternal and operator contamination. Sensitivity per center ranged from 76.5% to 91.3% and specificity from 64.7% to 93.3%. The false-negative rate was 8.3% (92/1108), and false-positive rate was 12.4% (137/1108). The 2 fertilization techniques provided similar sensitivity (80.9% vs 87.9%) and specificity (78.6% vs 69.9%). Multivariate analysis did not reveal any bias from patient clinical background, ovarian stimulation protocols, culture conditions, or embryo quality on testing accuracy of concordance. Moreover, concordances of embryonic cell-free DNA with trophectoderm and inner cell mass suggest that the embryonic cell-free DNA originates from both compartments of the human embryo. CONCLUSION: Noninvasive analysis of embryonic cell-free DNA in spent blastocyst culture media demonstrates high concordance with trophectoderm biopsy results in this large multicenter series. A noninvasive approach for prioritizing embryo euploidy offers important advantages such as avoiding invasive embryo biopsy and decreased cost, potentially increasing accessibility for a wider patient population.

The apoptotic pathway in fertile and subfertile men: a case-control and prospective study to examine the impact of merocyanine 540 bodies on ejaculated spermatozoa.

OBJECTIVE: To evaluate the presence of merocyanine 540 (M540) bodies and their impact on the measurement of apoptotic biomarkers in human spermatozoa. DESIGN: Case-control, prospective study. SETTING: Academic centers. PATIENT(S): Fertile and subfertile subjects. INTERVENTION(S): Semen samples from subfertile and fertile men, 11 per group, were analyzed for basic semen parameters and early (annexin-V binding) and late (terminal deoxynucleotidyl transferase dUTP nick end labeling [TUNEL]) sperm apoptotic biomarkers by flow cytometry. Samples were also stained with M540 to assess the presence of M540 apoptotic bodies. MAIN OUTCOME MEASURE(S): Presence of M540 apoptotic bodies. RESULT(S): Groups differed significantly in the expression of early and late apoptosis biomarkers. The percentage of M540 bodies between groups was not different. The exclusion of M540 bodies from TUNEL results did not have a significant impact on measurement in either fertile or subfertile groups. CONCLUSION(S): This study confirmed the occurrence of M540 bodies in semen and that male factor infertility is associated with an increased expression of apoptosis biomarkers. Moreover, we demonstrated that the presence of M540 bodies did not affect the quantification of apoptotic biomarkers in either group.

Preserved ex vivo inflammatory status in decidual cells from women with preterm labor and subclinical intrauterine infection.

OBJECTIVE: To compare the inflammatory response preserved ex vivo by decidual cells isolated from women who experienced preterm labor with and without subclinical intrauterine infection. METHODS: Fetal membranes were obtained after cesarean section from 35 women who delivered before 37 weeks of gestation following spontaneous preterm labor, with no clinical evidence of intrauterine infection. Decidua was microbiologically tested and cultured. Concentrations of anti-inflammatory cytokines (IL-2, IL-4, IL-10), pro-inflammatory cytokines (IL-6, IL-8, IL-1ß and TNF-α), and matrix metalloproteinases (MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9) were measured in the supernatants using Bio-Plex, and prostaglandin E(2) (PGE(2)) was measured by enzyme immunoassay. RESULTS: Subclinical infection was confirmed in 10 women (28.5%). Microorganisms isolated were Ureaplasma urealyticum (4), group B streptococci (3), Gardnerella vaginalis (1), and Escherichia coli (2). We found a significant increase of pro-inflammatory cytokines and a significant decrease of anti-inflammatory cytokines in supernatants from decidual cells obtained from women with preterm labor and subclinical intrauterine infection compared to women without infection. Secretion of MMP-1, MMP-8, MMP-9 and PGE(2) was significantly higher in infected women. Secretion of IL-8 by decidual cells from infected women persisted upon repeated in vitro culture passages. CONCLUSIONS: Almost 30% of idiopathic preterm labor cases were associated with subclinical intrauterine infection, and decidual cells isolated from these cases preserved an ex vivo inflammatory status after in vivo bacterial exposure.

The effect of age on the expression of apoptosis biomarkers in human spermatozoa.

OBJECTIVE: To evaluate the impact of age on the expression of apoptotic biomarkers in human spermatozoa. DESIGN: Cross sectional, prospective study. SETTING: Academic centers. PATIENT(S): Healthy volunteers with proven fertility, stratified by age (n = 25, range: 20-68 years). INTERVENTION(S): Examination of serum hormone levels and basic semen parameters, and assessment of early (plasma membrane translocation of phosphatidylserine) and late (DNA fragmentation) sperm apoptotic markers by flow cytometry (using Annexin-V binding and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling). MAIN OUTCOME MEASURE(S): Apoptosis markers. RESULT(S): Advancing male age was significantly and positively correlated with Annexin-V binding results. Although not significant, there was a clear trend for increased DNA fragmentation in the older groups. The age threshold for these observations appears to be 40 years. Advancing male age was positively correlated with FSH and sex hormone-binding globulin (SHBG) levels, and negatively correlated with sperm concentration. CONCLUSION(S): Advancing male age is associated with the expression of early apoptotic markers as evidenced by significantly increased plasma membrane translocation of phosphatidylserine, as well as with a more subtle proportion of sperm carrying DNA fragmentation. This study confirmed that male age is also associated with a decline in sperm concentration.

Developmental sperm contributions: fertilization and beyond.

The objective of this review was to examine the role of the various spermatozoal components suspected of actively participating in early human development. The contributions of the fertilizing spermatozoon to the oocyte include, as a minimum, the delivery of the DNA/chromatin, a putative oocyte-activating factor (OAF), and a centriole. Recent data indicate that spermatozoa may also provide the zygote with a unique suite of paternal mRNAs; some transcripts might be crucial for early and late embryonic development and deficient delivery, or aberrant transcription might contribute to abnormal development and arrest. Clinical evidence from assisted reproduction suggests that failure to complete the fertilization process, syngamy, or early cleavage might be the result of an early paternal effect. It is speculated that an abnormal release of a putative OAF and/or dysfunctions of the centrosome and cytoskeletal apparatus may mediate these effects. On the other hand, a later paternal effect resulting in embryonic failure to achieve implantation, pregnancy loss, and/or developmental abnormalities resulting from "carried over" sublethal effects may be associated with sperm nuclear/chromatin defects, including the presence of aneuploidy, genetic anomalies, DNA damage, and possibly other causes. These findings highlight the need for continuous monitoring of clinical results.

Comparison of the efficacy of the aromatase inhibitor letrozole and clomiphene citrate as adjuvants to recombinant follicle-stimulating hormone in controlled ovarian hyperstimulation: a prospective, randomized, blinded clinical trial.

OBJECTIVE: To study the efficacy of the aromatase inhibitor letrozole as adjuvant to recombinant FSH (rFSH) in controlled ovarian hyperstimulation (COH). DESIGN: Prospective, randomized, and blinded clinical study. SETTING: Academic tertiary institute. PATIENT(S): Forty-one patients with unexplained infertility undergoing intrauterine insemination (IUI) therapy were randomized to receive either letrozole or clomiphene citrate (CC) as adjuvants to rFSH. INTERVENTION(S): From day 3 to 7 of the cycle 2.5 mg/d letrozole or 100 mg/d CC were administrated. All patients received 75 IU rFSH starting on day 7 of stimulation until the day of hCG administration. Ovulation was triggered with recombinant hCG (250 microg) when the leading follicle(s) reached 18 mm in diameter. A single IUI was performed 36 hours later. The luteal phase was supplemented with micronized progesterone vaginally. MAIN OUTCOME MEASURE(S): Ovarian stimulation response (E(2) levels and number of follicles) was our primary outcome. RESULT(S): There were no differences in demographic characteristics between groups. Although there was a significantly lower peak serum E(2) level in the group receiving letrozole + rFSH compared with CC + rFSH (914 +/- 187 vs. 1,207 +/- 309 pg/mL, respectively; P<.007), there were no differences in the number of mature (>16 mm) preovulatory follicles. A significantly higher endometrial thickness was observed at the time of hCG administration in patients that received letrozole (9.5 +/- 1.5 mm vs. 7.3 +/- 1.1 mm; P=.0001). The clinical pregnancy rate was similar between groups (23.8% vs. 20%, respectively). CONCLUSION(S): The aromatase inhibitor letrozole appears to constitute a good alternative to CC in patients with unexplained infertility undergoing gonadotropin-stimulated COH cycles combined with IUI therapy.

Mitochondrial membrane potential integrity and plasma membrane translocation of phosphatidylserine as early apoptotic markers: a comparison of two different sperm subpopulations.

OBJECTIVE: To examine whether a relationship exists between loss of mitochondrial transmembrane potential and plasma membrane translocation of phosphatidylserine (PS) in subpopulations of human spermatozoa of men consulting for infertility. SETTING: A tertiary institutional research center. DESIGN: Prospective observational study. PATIENT(S): Twelve infertile men and five fertile controls were compared. INTERVENTION(S): Sperm subpopulations were compared after density gradient separation. MAIN OUTCOME MEASURE(S): Mitochondrial membrane potential was measured with a cationic dye, translocation of PS was evaluated with Annexin-V binding, and motion parameters were assessed manually. RESULT(S): In both the study and control groups and compared with the high-motility fraction, the low-motility fraction had significantly lower sperm motility and normal morphology, and significantly higher percentage of cells with disrupted mitochondrial membrane potential and plasma membrane PS translocation. There was a positive and significant correlation in both subfertile and control groups between the percentages of Annexin-V+ live cells and cells with mitochondrial membrane potential disruption (r = 0.82 and r = 0.85, respectively). CONCLUSION(S): The correlation of plasma membrane PS translocation and loss of mitochondrial membrane potential is suggestive of an early apoptosis phenotype, as is typically observed in somatic cells identified in sperm subpopulations with percentage of low-motile cells. We speculate that such changes might be used as diagnostic markers of sperm dysfunction(s) and that increased levels found in subfertile men might be indicators of reduced fertility potential.

Controlled ovarian hyperstimulation protocols for in vitro fertilization: two decades of experience after the birth of Elizabeth Carr.

OBJECTIVE: To critically discuss the current protocols for the management of controlled ovarian hyperstimulation in assisted reproduction technology. DESIGN: Review of the literature and presentation of our experience. MAIN OUTCOME MEASURE(S): Ovarian response (peak serum estrogen levels, number of oocytes retrieved, quality of oocytes and embryos) and pregnancy outcome (clinical, delivery, and multiple pregnancy rates). RESULT(S): Controversies still exist regarding selection of gonadotropin preparation, choice of adjuvant therapy with GnRH analogues, and use of oral contraceptive pills. Patients identified as intermediate responders have an excellent outcome with adjuvant therapy with either a GnRH agonist (long protocol) or a GnRH antagonist, but tailoring of gonadotropin dose must be performed to achieve optimized results. High responders perform favorably with gentler gonadotropin stimulation that minimizes the occurrence of ovarian hyperstimulation syndrome. On the other hand, results in low responders remain suboptimal both in terms of ovarian response and oocyte/embryo quality in spite of a variety of stimulation regimens used. CONCLUSION(S): Ovarian stimulation is a critical step in in vitro fertilization therapy. A variety of controlled ovarian hyperstimulation regimens are available and efficacious, but individualization of management is essential and depends on assessment of the ovarian reserve. Identification of the etiologies of poor ovarian response constitutes a formidable challenge facing reproductive endocrinologists.

[Prognostic value on recovery rates for the application of sperm preparation techniques and their evaluation in sperm function]. / Valor pronóstico en las tasas de recuperación para la aplicación de técnicas de preparación seminal y su evaluación en la función espermática.

OBJECTIVE: To evaluate sperm recovery and total sperm motility in three different sperm preparation techniques (density gradient, simple washing and swim-up). PATIENTS AND METHODS: A total of 290 subjects were randomly evaluated from November 2001 to March 2003. The density gradient method required Isolate (upper and lower layers). Centrifugation was performed at 400 g for 10 minutes and evaluation was done using the Makler counting chamber. The simple washing method included the use of HTF-M complemented with 7.5% of SSS, with centrifugation at 250 g, obtaining at the end 0.5 mL of the sperm sample. The swim-up method required HTF-M complemented with 7.5% of SSS, with an incubation period of 60 minutes at 37 degrees C. RESULTS: The demographic characteristics evaluated through their standard error, 95% ICC, and 50th percentile were similar. The application of multiple comparison tests and analysis of variance showed significant differences between the sperm preparations before and after capacitation. It was observed a superior recovery rate with the density gradient and swim-up methods; nevertheless, the samples used for the simple washing method showed a diminished sperm recovery from the original sample. CONCLUSIONS: Sperm preparation techniques have become very useful in male infertility treatments allowing higher sperm recovery and motility rates. The seminal parameters evaluated from the original sperm sample will determine the best sperm preparation technique in those patients who require it.

Intestinal adhesion to the abdominal wall after skin closure with octylcyanoacrylate.

Octylcyanoacrylate tissue adhesive glue is a wound closure device recently approved by the U.S. Food and Drug Administration. Few complications have been reported regarding the liquid adhesive entering the wound. The following report involves a patient who developed intestinal occlusion secondary to octylcyanoacrylate used for skin closure in laparoscopic surgery.

[Activation in the metaloproteinases complex in the follicle-embryonic generative capability]. / Activación en el complejo de metaloproteinasas en la capacidad generativa folículo-embrionaria.

OBJECTIVE: To evaluate the impact of the enzymatic inhibition complex of metaloproteinases [TIMP(MMP-3 stromelisine-1)] in follicle/genesis processes and their ovule/embryonic subsequent development in stimulated cycles. TYPE OF STUDY: Prospective longitudinal in research center. MATERIALS AND METHODS: A total of 20 patients were evaluated in vitro fertilization cycles measuring matrix metaloproteinases concentrations in days 3 and 12 of ovarian stimulation, as well as in the follicular liquid at the moment of ovarian retrieval. The determination of [TIMP/(MMP-3 stromelisine-1)] was done by ELISA and monoclonal antibodies type of immunoassay methods. For its statistical evaluation were applied linear regression models ( r/r2 ) and Kolmogorov-Smirov test comparing the two groups where values were expressed in agreement at its mean, standard deviation and a significance of p < 0.05. RESULTS: For regression models was found a positive correlation between basal FSH and the age of patients [(r2 = 0.26)(p = 0.003)], dividing groups in older and younger patients than 35 years; it was observed significant difference in metaloproteinases concentration as in serum concentration (days 3 and 12 of stimulation) as in the follicular liquid. A decrease in the 14% [(TIMP/(MMP-3/stromelisine-1)] complex concentration was increasing in accordance at the female patients age. CONCLUSIONS: The matrix metaloproteinases complex study has allowed observing a status not only in the ovular quality but in the embryonic development and fertilization processes too.

Evaluación de la penetración del medio de cultivo a la cavidad uterina como efecto del lavado cervical previo a la transferencia embrionaria: estudio prospectivo y observacional en piezas obtenidas por histerectomía / Evaluation of the medium culture penetration into the uterus cavity after cervical lavage during embryo transfer: A prospective and observational trial in uterus obtained trough hysterectomy

La realización del lavado endocervical previo a la transferencia embrionaria, con la consiguiente remoción de moco y elementos de descamación cervical, se ha convertido en una práctica cotidiana en muchos centros de reproducción asistida. Sin embargo, el paso o no de estos medios hacia la cavidad uterina, con la consecuente modificación en el microambiente endouterino no ha sido probado. Para este fin, se realizó un estudio prospectivo en 16 pacientes con indicación de histerectomía ginecológica, a las cuales se les realizó preparación y lavado cervical previo al procedimiento quirúrgico similar al proceso de transferencia embrionaria, para evaluar los límites de invasión en forma ulterior. La edad promedio de las pacientes fue de 36.4 ñ 8.6 años. Los diagnósticos preoperatorios fueron sangrado uterino anormal (n=4), miomatosis uterina (n=4), adenomiosis (n=4), pólipos endometriales (n=3) y dolor pélvico crónico (n=1). El peso uterino promedio fue de 127.5 ñ 55.4 g el tiempo quirúrgico de 48.8 ñ 12.5 mm. El paso del medio de contraste hacia la cavidad uterina se informó sólo en uno de los casos (0.62 por ciento), por lo que concluimos que la aplicación de este procedimiento en los procesos de transferencia es seguro y no modifica las condiciones intrauterinas para el desarrollo embrionario.

Estudio prospectivo y aleatorio del impacto de misoprostol (PgE1) en las tasas de embarazo con inseminación intrauterina (IIU): Informe preliminar / A prospective randomized trial of the impact of misoprostol (PgE1) on pregnancy outcome after intrauterine insemination (IUI) therapy: a preliminary study

La aplicación de prostaglandinas (Pg) en el campo reproductivo, aunque controversial, ha jugado un papel importante dentro de los fenómenos fisiológicos del aparato reproductivo humano. Por otro lado, el uso de los procedimientos de hiperestimulación ovárica controlada e inseminación intrauterina incrementan en forma considerable las expectativas reproductivas en ciertos grupos de pacientes. El objetivo de este trabajo fue valorar el efecto del uso de prostaglandinas (específicamente del misoprostol), en las tasas de embarazo, en aquellas pacientes que se encuentren bajo tratamiento específico de hiperestimulación ovárica controlada e inseminación intrauterina. Se estudiaron 59 ciclos de hiperestimulación ovárica e inseminación intrauterina, en donde al grupo de estudio (n=29) se le aplicaron 200 microgramos de prostaglandina E1 (misoprostol) por vía intravaginal inmediatamente después de la inseminación, comparado con el grupo control (n=30), en donde las características demográficas fueron similares. No se observaron diferencias en cuanto a edad, evaluación endocrinológica basal (FSH, LH y estradiol), así como día de la aplicación de la hCG y número de ámpulas utilizadas durante el tratamiento. Sin embargo, un efecto significativo fue encontrado en la tasa de embarazo evaluada por ambos grupos siendo de 20 por ciento en el grupo control comparado con 31 por ciento en el grupo de pacientes con prostaglandinas. A partir de estos resultados hemos podido comprobar el efecto benéfico con el uso de misoprostol en inseminación intrauterina, lo cual se ve reflejado en un incremento en las tasas de embarazo clínico.

Análisis comparativo del desarrollo multifolicular con la aplicación de FSH recombinante vs. FSH urinaria en los resultados de fertilización in vitro / A comparative analysis of multifollicular development using recombinant FSH vs. urinary FSH in the in-vitro fertrilization outcome

La interacción entre los diversos factores intrafoliculares relacionados con la competitividad ovular y el consecutivo desarrollo embrionario juega un papel preponderante para la transferencia de embriones de alta calidad en los programas de fertilización in vitro. La utilización de gonadotropinas urinarias para la formación de una cohorte folicular homogénea en estimulación controlada ha tenido una extensa aplicación. En los últimos años la tecnología recombinante en la preparación de este tipo de compuestos ha venido a correlacionarse con la formación de óvulos de mejor calidad y la presencia de mayores tasas de embarazo. Por este motivo se desarrolló un estudio prospectivo, longitudinal y comparativo de la aplicación de gonadotropinas de tipo urinario y recombinante valorando el desarrollo óvulo/embrionario. Se incluyeron un total de 100 pacientes para este trabajo, de las cuales 56 recibieron FSH recombinante (grupo I) y 44 una combinación de derivados urinarios (grupo II). Por diseño de estudio no se observaron diferencias en cuanto a edad, peso e índice de masa corporal; por otro lado, la valoración de la reserva ovárica no presenta diferencias en ambos grupos. Sin embargo, las pacientes que utilizaron la combinación de gonadotropinas urinarias requirieron un número mayor de ámpulas comparado con el grupo de recombinante [31.7 ñ 8.6 vs. 20.7 ñ 6.4 (p < 0.001)]. No se observaron diferencias en la concentración final de estradiol, día de la aplicación de hCG así como grosor endometrial. Aunque no hubo diferencias en el número de óvulos maduros (metafase I y II), el número de óvulos fertilizados mostró ser mayor en el grupo de recombinante [5.9 ñ 3.7 vs. 3.4 ñ 2.3 (p < 0.02)]. De esta manera, se transfirió un número mayor de preembriones en el mismo grupo (3.4 ñ 1.7 vs. 1.9 ñ 2.2 (p < 0.004)]. Las tasas de embarazo fueron de 34.3 por ciento y 29.6 por ciento para el grupo I y II respectivamente.

Evaluación de la supresión nociceptiva en el status postoperatorio laparoscópico: Estudio prospectivo, aleatorio comparativo con la inclusión de un grupo control / Evaluation of nocicepative suppression in the post-operative laparoscopic status: A prospective, randomized and comparative study including a control group

En los últimos años la cirugía laparoscópica ha venido a convertirse en un procedimiento altamente demandado, tanto por la accesibilidad en su uso y aplicación, como por la facilidad para el diagnóstico y tratamiento de ciertas entidades nosológicas en el campo ginecológico. El manejo del dolor postoperatorio es una de las condiciones relacionadas como causa importante de morbilidad en la realización de este tipo de procedimientos. Con el objetivo de evaluar la supresión nociceptiva postoperatoria en los procedimientos laparoscópicos, se llevó a cabo un estudio prospectivo y longitudinal para la evaluación de esta condición. Un total de 45 pacientes fueron incluidas en el estudio. Tres grupos de pacientes fueron distribuidos aleatoriamente para recibir dos tipos de anestésicos colocados en el fondo de saco posterior y pliegue vésico-uterino. Al grupo A (n=15) se le administró bupivacaína; mientras que el grupo B (n=15) recibió ropivacaína y el C o control, solución salina. La valoración del dolor fue realizada a través de la aplicación de la escala visual análoga (EVA) junto con los parámetros de frecuencia cardiaca y tensión arterial a intervalos de 15 minutos en el postoperatorio inmediato. Por diseño de estudio no se observaron diferencias en cuanto a las características generales. La edad, peso, estatura e índice de masa corporal (IMC) fueron similares entre grupos. No hubo diferencias en los tiempos tanto quirúrgicos como anestésicos. Las constantes vitales permanecieron inalterables. Sin embargo, cuando se valoró el efecto nociceptivo se encontró una diferencia altamente significativa entre el grupo control y los grupos de estudio. Por los efectos analgésicos y el menor efecto tóxico sistémico el uso de ropivacaína ha mostrado ser un medicamento ideal en analgesia preventiva.

Influencia de los factores intrafoliculares a nivel ovárico durante el desarrollo óvulo/embrionario / Potential of the intrafolicular factors during oocyte/embryo development

Una serie de factores se encuentra relacionada con los eventos de fertilización y desarrollo embrionario. Cada uno de estos presenta un significado en la interrelación de diversos eventos moleculares relacionados con la calidad ovular y embrionaria. Los fenómenos dinámicos relacionados con el ambiente endocrino-paracrino determinan la relación de cada uno de estos dentro de la foliculogénesis ovárica. La presencia de factores de crecimiento, factor de crecimiento vascular endotelial (FCVE), óxido nítrico, leptinas, etc.) muestra una relación proporcional en el proceso de maduración ovular. Es por esto que cada uno de ellos puede expresarse como biomarcadores de viailidad embrionaria y su consiguiente implantación.

Transferencia embrionaria: un paso crítico en reproducción asistida / Embryos transfer: A critical step in assisted reproduction

El advenimiento de nuevas técnicas y procedimientos relacionados con el desarrollo embrionario, y su evento final, la transferencia embrionaria; han incrementado en forma significativa el número de embarazos obtenidos a través de las diferentes técnicas de reproducción asistida. La transferencia embrionaria es probablemente la parte final y decisiva dentro de los programas de fertilización in vitro, en donde el éxito estará determinado por la dificultad técnica y las características inherentes al procedimiento. La estandarización y aplicación de las técnicas actuales en el proceso de transferencia embrionaria permitirá a corto plazo incrementar, las tasas tanto de embarazo como de implantación en los diferentes centros reproductivos.

El diagnóstico y tratamiento del factor masculino en la era del ICSI / Diagnosis and treatment of male factor in ICSI times

Actualmente somos testigos del avance en las técnicas de Reproducción Asistida que con el advenimiento de la inyección intracitoplasmática de esperma (ICSI), han venido a cumplir los objetivos reproductivos en pacientes que cuentan con un factor masculino de base. Sin embargo, el uso de estas técnicas de micromanipulación ha dado una pauta reproductiva, en ausencia de un diagnóstico etiológico y fisiopatológico. El estudio andrológico sistematizado de las características dinámicas y los aspectos funcionales espermáticos, complementados por la valoración endocrinourológica deben implementarse para un manejo diagnóstico y terapéutico reproductivo adecuado.