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1.
Chimia (Aarau) ; 78(3): 129-134, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38547014

RESUMEN

Catalytic conversions in fine-chemical and pharmaceutical production are increasingly performed in trickle-bed rectors. Optimisation of these processes is usually based on end of pipe measurement made at specific residence times. This process is both time-consuming and the data sometimes challenging to interpret. In the present work, operando nuclear magnetic resonance (NMR) techniques both at the scale of the whole bed (global) and spatially resolved within the bed (local) are used to gain new insights into the catalytic conversion process under reaction conditions. Spatially resolved spectroscopic and diffusion-T2-relaxation (D-T2) methods interrogate local differences in chemical conversion and selectivity, and mass transport (molecular self-diffusion) respectively, thereby providing valuable information for process simulation models. This capability is demonstrated using the continuous flow three phase (gas-liquid-solid) hydrogenation of benzonitrile over a fixed bed of 0.5 wt% Pd/Al2O3 catalyst pellets yielding toluene and benzylamine. Global 1H spectroscopic and D-T2 were used to monitor chemical conversion and the approach to steady state; these were subsequently followed by spatially resolved 1H spectra and spatially resolved D-T2 correlations to examine the local differences in axial conversion and selectivity of the catalyst bed packing. At steady-state a global conversion of 63% was achieved with 65% and 25% selectivity to benzylamine and toluene respectively. Heterogeneities in the local (axial) conversion and selectivity differed by 31% along the total catalyst bed length. These techniques should be applicable to many three-phase heterogeneous catalytic systems provided that the T2 relaxation time of the reactants and products is not prohibitively small.

2.
Environ Health Perspect ; 131(12): 127015, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38117586

RESUMEN

BACKGROUND: Phthalate exposures are ubiquitous during pregnancy and may contribute to racial and ethnic disparities in preterm birth. OBJECTIVES: We investigated race and ethnicity in the relationship between biomarkers of phthalate exposure and preterm birth by examining: a) how hypothetical reductions in racial and ethnic disparities in phthalate metabolites might reduce the probability of preterm birth; and b) exposure-response models stratified by race and ethnicity. METHODS: We pooled individual-level data on 6,045 pregnancies from 16 U.S. cohorts. We investigated covariate-adjusted differences in nine urinary phthalate metabolite concentrations by race and ethnicity [non-Hispanic White (White, 43%), non-Hispanic Black (Black, 13%), Hispanic/Latina (38%), and Asian/Pacific Islander (3%)]. Using g-computation, we estimated changes in the probability of preterm birth under hypothetical interventions to eliminate disparities in levels of urinary phthalate metabolites by proportionally lowering average concentrations in Black and Hispanic/Latina participants to be approximately equal to the averages in White participants. We also used race and ethnicity-stratified logistic regression to characterize associations between phthalate metabolites and preterm birth. RESULTS: In comparison with concentrations among White participants, adjusted mean phthalate metabolite concentrations were consistently higher among Black and Hispanic/Latina participants by 23%-148% and 4%-94%, respectively. Asian/Pacific Islander participants had metabolite levels that were similar to those of White participants. Hypothetical interventions to reduce disparities in metabolite mixtures were associated with lower probabilities of preterm birth for Black [13% relative reduction; 95% confidence interval (CI): -34%, 8.6%] and Hispanic/Latina (9% relative reduction; 95% CI: -19%, 0.8%) participants. Odds ratios for preterm birth in association with phthalate metabolites demonstrated heterogeneity by race and ethnicity for two individual metabolites (mono-n-butyl and monoisobutyl phthalate), with positive associations that were larger in magnitude observed among Black or Hispanic/Latina participants. CONCLUSIONS: Phthalate metabolite concentrations differed substantially by race and ethnicity. Our results show hypothetical interventions to reduce population-level racial and ethnic disparities in biomarkers of phthalate exposure could potentially reduce the probability of preterm birth. https://doi.org/10.1289/EHP12831.


Asunto(s)
Exposición Materna , Ácidos Ftálicos , Nacimiento Prematuro , Femenino , Humanos , Recién Nacido , Embarazo , Biomarcadores , Etnicidad , Nacimiento Prematuro/epidemiología , Exposición Materna/efectos adversos , Ácidos Ftálicos/efectos adversos , Grupos Raciales
3.
F S Rep ; 3(3): 184-191, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36212571

RESUMEN

Objective: To investigate cumulative live birth rates (CLBRs) in cycles with and without preimplantation genetic testing for aneuploidy (PGT-A) among patients aged <35 and 35-37 years. Design: Retrospective cohort study. Setting: Society for Assisted Reproductive Technology reporting clinics. Patients: A total of 31,900 patients aged ≤ 37 years with initial oocyte retrievals between January 2014 and December 2015 followed through December 2016. Interventions: None. Main outcome measures: The primary outcome was CLBR among patients aged <35 and 35-37 years. The secondary outcomes included multifetal births, miscarriage, preterm birth, perinatal mortality, and the time to pregnancy resulting in a live birth. Adjusted odds ratios (aORs) adjusting for age, body mass index, total 2 pronuclei embryos, embryos transferred, and follow-up timeframe. Results: Among patients aged <35 years, PGT-A was associated with reduced CLBRs (70.6% vs. 71.1%; aOR, 0.82; 95% CI [confidence interval], 0.72-0.93). No association was found between PGT-A and CLBRs among patients aged 35-37 years (66.6% vs. 62.5%; aOR, 0.92; 95% CI, 0.83-1.01). Overall, there was no significant difference in the miscarriage rate (aOR, 0.97; 95% CI, 0.82-1.14). Multifetal birth rates were lower with PGT-A (9.5% vs. 23.1%); however, PGT-A was not an independent predictor of multifetal birth (aOR, 1.11; 95% CI, 0.91-1.36). The average time to pregnancy resulting in a live birth was 2.37 months (SD 3.20) for untested transfers vs. 4.58 months (SD 3.53) for PGT-A transfers. Conclusions: In women aged <35, the CLBR was lower with PGT-A than with the transfer of untested embryos. In women aged 35-37 years, PGT-A did not improve CLBRs.

4.
Fertil Steril ; 118(4): 680-687, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36085173

RESUMEN

OBJECTIVE: To determine whether a low oocyte maturity ratio in a cohort of oocytes from an in vitro fertilization cycle predicts outcomes and to examine clinical factors associated with oocyte maturity. DESIGN: A retrospective cohort study. SETTING: An academic medical center. INTERVENTION(S): Determination of oocyte maturity immediately after the retrieval and 6 hours later if intracytoplasmic sperm injection was performed. MAIN OUTCOME MEASURE(S): The primary outcome was live birth rate after the first embryo transfer. Secondary outcomes included clinical pregnancy, miscarriage, and fertilization rates. RESULT(S): After adjusting for age, preimplantation genetic testing, and number of embryos transferred, we found that a low oocyte maturity ratio was associated with a decreased live birth rate (adjusted odds ratio [AOR], 0.41; 95% confidence interval [CI], 0.22-0.77) and clinical pregnancy rate (AOR, 0.32; 95% CI, 0.17-0.61). We did not find a relationship between oocyte maturity and miscarriage rate (AOR, 0.25; 95% CI, 0.03-1.91) or fertilization rate (Welch test). The number of 2 pronuclei embryos per retrieved oocyte was found to be associated with the maturity ratio at retrieval. Patients with anovulation had slightly reduced oocyte maturity compared with other diagnostic groups. CONCLUSION(S): Low oocyte maturity ratio is an important factor related to poor in vitro fertilization outcomes, including decreased pregnancy and live birth rates.


Asunto(s)
Aborto Espontáneo , Inyecciones de Esperma Intracitoplasmáticas , Aborto Espontáneo/epidemiología , Aborto Espontáneo/etiología , Tasa de Natalidad , Femenino , Fertilización In Vitro/efectos adversos , Humanos , Nacimiento Vivo , Masculino , Recuperación del Oocito , Oocitos , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Semen , Inyecciones de Esperma Intracitoplasmáticas/efectos adversos
5.
J Occup Environ Med ; 64(10): 831-838, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35902368

RESUMEN

OBJECTIVE: We examined associations between occupation and semen parameters in demonstrably fertile men in the Study for Future Families. METHODS: Associations of occupation and workplace exposures with semen volume, sperm concentration, motility, and morphology were assessed using generalized linear modeling. RESULTS: Lower sperm concentration and motility were seen in installation, maintenance, and repair occupations. Higher exposure to lead, and to other toxicants, was seen in occupations with lower mean sperm concentrations (prevalence ratio for lead: 4.1; pesticides/insecticides: 1.6; solvents: 1.4). Working with lead for more than 3 months was associated with lower sperm concentration, as was lead exposure outside of work. CONCLUSIONS: We found evidence in demonstrably fertile men for reduced sperm quality with lead, pesticide/herbicide, and solvent exposure. These results may identify occupations where protective measures against male reproductive toxicity might be warranted.


Asunto(s)
Herbicidas , Insecticidas , Plaguicidas , Humanos , Plomo , Masculino , Ocupaciones , Plaguicidas/toxicidad , Semen , Solventes , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides
6.
JAMA Pediatr ; 176(9): 895-905, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35816333

RESUMEN

Importance: Phthalate exposure is widespread among pregnant women and may be a risk factor for preterm birth. Objective: To investigate the prospective association between urinary biomarkers of phthalates in pregnancy and preterm birth among individuals living in the US. Design, Setting, and Participants: Individual-level data were pooled from 16 preconception and pregnancy studies conducted in the US. Pregnant individuals who delivered between 1983 and 2018 and provided 1 or more urine samples during pregnancy were included. Exposures: Urinary phthalate metabolites were quantified as biomarkers of phthalate exposure. Concentrations of 11 phthalate metabolites were standardized for urine dilution and mean repeated measurements across pregnancy were calculated. Main Outcomes and Measures: Logistic regression models were used to examine the association between each phthalate metabolite with the odds of preterm birth, defined as less than 37 weeks of gestation at delivery (n = 539). Models pooled data using fixed effects and adjusted for maternal age, race and ethnicity, education, and prepregnancy body mass index. The association between the overall mixture of phthalate metabolites and preterm birth was also examined with logistic regression. G-computation, which requires certain assumptions to be considered causal, was used to estimate the association with hypothetical interventions to reduce the mixture concentrations on preterm birth. Results: The final analytic sample included 6045 participants (mean [SD] age, 29.1 [6.1] years). Overall, 802 individuals (13.3%) were Black, 2323 (38.4%) were Hispanic/Latina, 2576 (42.6%) were White, and 328 (5.4%) had other race and ethnicity (including American Indian/Alaskan Native, Native Hawaiian, >1 racial identity, or reported as other). Most phthalate metabolites were detected in more than 96% of participants. Higher odds of preterm birth, ranging from 12% to 16%, were observed in association with an interquartile range increase in urinary concentrations of mono-n-butyl phthalate (odds ratio [OR], 1.12 [95% CI, 0.98-1.27]), mono-isobutyl phthalate (OR, 1.16 [95% CI, 1.00-1.34]), mono(2-ethyl-5-carboxypentyl) phthalate (OR, 1.16 [95% CI, 1.00-1.34]), and mono(3-carboxypropyl) phthalate (OR, 1.14 [95% CI, 1.01-1.29]). Among approximately 90 preterm births per 1000 live births in this study population, hypothetical interventions to reduce the mixture of phthalate metabolite levels by 10%, 30%, and 50% were estimated to prevent 1.8 (95% CI, 0.5-3.1), 5.9 (95% CI, 1.7-9.9), and 11.1 (95% CI, 3.6-18.3) preterm births, respectively. Conclusions and Relevance: Results from this large US study population suggest that phthalate exposure during pregnancy may be a preventable risk factor for preterm delivery.


Asunto(s)
Ácidos Ftálicos , Nacimiento Prematuro , Adulto , Biomarcadores , Femenino , Humanos , Recién Nacido , Exposición Materna/efectos adversos , Oportunidad Relativa , Ácidos Ftálicos/orina , Embarazo , Mujeres Embarazadas , Nacimiento Prematuro/epidemiología
7.
Fertil Steril ; 118(3): 465-472, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35835597

RESUMEN

OBJECTIVE: To compare the cumulative live birth rates (CLBRs) and cost effectiveness of intracytoplasmic sperm injection (ICSI) and conventional in vitro fertilization (cIVF) for non-male factor infertility. DESIGN: A retrospective cohort study. SETTING: Society for Assisted Reproductive Technology clinics. PATIENT(S): A total of 46,967 patients with non-male factor infertility with the first autologous oocyte retrieval cycle between January 2014 and December 2015. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The primary outcomes were CLBR, defined as up to 1 live birth from an autologous retrieval cycle between 2014 and 2015, and linked fresh and frozen embryo transfers through 2016. The secondary outcomes included miscarriage rate, 2 pronuclei per oocyte retrieved, and the total number of transferred and frozen embryos. Analyses were performed on subsamples with and without preimplantation genetic testing for aneuploidy (PGT-A). A cost analysis was performed to determine the costs accrued by ICSI. RESULT(S): Among cycles without PGT-A in patients with non-male factor infertility, the CLBR was 60.9% for ICSI cycles vs. 64.3% for cIVF cycles, a difference that was not significantly different after adjustment for covariates (adjusted risk ratio, 0.99; 95% confidence interval, 0.99-1.00). With PGT-A, no difference in CLBR was found between ICSI and cIVF cases after adjustment (64.7% vs. 69.0%, respectively; adjusted risk ratio, 0.97; 95% confidence interval, 0.93-1.01). The patients were charged an estimated additional amount of $37,476,000 for ICSI without genetic testing and an additional amount of $7,213,500 for ICSI with PGT-A over 2 years by Society for Assisted Reproductive Technology clinics. CONCLUSION(S): In patients with non-male factor infertility, ICSI did not improve CLBR. Given the additional cost and the lack of CLBR benefit, our data show that the routine use of ICSI in patients with non-male factor infertility is not warranted.


Asunto(s)
Infertilidad , Inyecciones de Esperma Intracitoplasmáticas , Aneuploidia , Tasa de Natalidad , Femenino , Fertilización In Vitro/efectos adversos , Humanos , Infertilidad/diagnóstico , Infertilidad/terapia , Nacimiento Vivo , Masculino , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Semen , Inyecciones de Esperma Intracitoplasmáticas/efectos adversos
10.
Am J Obstet Gynecol ; 227(2): 129-135, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35150636

RESUMEN

The practice of in vitro fertilization has changed tremendously since the birth of the first in vitro fertilization infant in 1978. With the success of early in vitro fertilization programs in the United States, there was a substantial rise in twin births nationwide. In the mid-1990s, more than 30% of in vitro fertilization cycles resulted in twin or higher-order multifetal pregnancies. Since that time, we not only have witnessed improvements in laboratory and treatment efficacy but also have seen a dramatic impact on pregnancy outcomes, specifically regarding twin pregnancies. Because the field evolved and the risks of multifetal pregnancies became more salient, in 2019, the rate of twin pregnancies had dropped to <7% of cycles. This improvement was largely because of technical advancements and revised professional guidance: culturing embryos longer before transfer, improved freezing technology, embryo preimplantation genetic testing, and revised professional guidance regarding the number of embryos to transfer. These developments have led to single-embryo transfer becoming the standard of care in most scenarios. We used national in vitro fertilization surveillance data of all autologous in vitro fertilization cycles from 1996 to 2019 to illustrate trends in the following improved outcomes: autologous embryo transfer cycles involving blastocyst-stage embryos, vitrified embryos, preimplantation genetic testing cycles, total number of embryos being transferred per cycle, and single-embryo transfer usage over time. Among deliveries from autologous embryo transfers, we highlighted trends in singleton births over time and proportion of deliveries involving twins, triplets, quadruplets, or greater. The notable progress in reducing the rate of multifetal pregnancies with in vitro fertilization was largely attributed to a series of technical and clinical actions, culminating in an 80% reduction in the incidence of multiple births without a loss in overall treatment effectiveness.


Asunto(s)
Recién Nacido de Bajo Peso , Nacimiento Prematuro , Acetaminofén , Aspirina , Femenino , Fertilización In Vitro , Humanos , Recién Nacido , Recien Nacido Prematuro , Vigilancia de la Población , Embarazo , Resultado del Embarazo , Embarazo Múltiple , Embarazo Gemelar , Nacimiento Prematuro/epidemiología , Técnicas Reproductivas Asistidas , Estados Unidos/epidemiología
11.
Fertil Steril ; 117(4): 803-810, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35216830

RESUMEN

OBJECTIVE: To determine if transfer of fresh embryos derived from fresh or cryopreserved donor oocytes yields a higher live birth rate. DESIGN: Historical cohort study. SETTING: Society for Assisted Reproductive Technology Clinic Outcome Reporting System database. PATIENT(S): A total of 24,663 fresh embryo transfer cycles of donor oocytes. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The primary outcome was live births per number of embryos transferred on day 5. The secondary outcomes included number of infants per embryo transfer, surplus embryos cryopreserved, and characterization of US oocyte recipients. RESULT(S): A total of 16,073 embryo transfers were from fresh oocytes and 8,590 were from cryopreserved oocytes. Recipient age, body mass index (BMI), gravidity, and parity were similar between the groups. Most recipients were of White non-Hispanic race (66.9%), followed by Asian (13.7%), Black non-Hispanic (9.3%), and Hispanic (7.2%). Fresh oocyte cycles were more likely to use elective single embryo transfer (42.5% vs. 37.8%) or double embryo transfer (53.2% vs. 50.4%) and resulted in more surplus embryos for cryopreservation (4.6 vs. 1.2). The live birth rate from fresh oocytes was 57.5% vs. 49.7% from cryopreserved oocytes. Negative predictors of live birth included the use of cryopreserved oocytes (odds ratio [OR] 0.731, 95% confidence interval [CI] 0.665-0.804), Black non-Hispanic race (OR 0.603, 95% CI 0.517-0.703), Asian race (OR 0.756, 95% CI 0.660-0.867), and increasing recipient BMI (OR 0.982, 95% CI 0.977-0.994) after controlling for recipient age, number of embryos transferred on day 5, and unexplained infertility diagnosis. The proportion of multifetal deliveries was greater in cycles utilizing fresh (26.4%) vs. cryopreserved (20.6%) oocytes. CONCLUSION(S): The live birth rate is higher with use of fresh oocytes vs. cryopreserved oocytes in fresh embryo transfer cycles. Negative live birth predictors include recipient Black non-Hispanic or Asian race and increasing BMI.


Asunto(s)
Tasa de Natalidad , Fertilización In Vitro , Estudios de Cohortes , Criopreservación , Transferencia de Embrión/efectos adversos , Transferencia de Embrión/métodos , Femenino , Fertilización In Vitro/efectos adversos , Humanos , Inseminación , Nacimiento Vivo , Oocitos , Embarazo , Índice de Embarazo , Técnicas Reproductivas Asistidas , Estudios Retrospectivos
12.
Fertil Steril ; 117(1): 75-85, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34656303

RESUMEN

OBJECTIVE: To determine if 6-month folic acid (5 mg) and zinc (30 mg) supplementation impacts sperm DNA methylation patterns. DESIGN: A multicenter, double-blind, block randomized, placebo-controlled trial titled "The Folic Acid and Zinc Supplementation Trial (FAZST)." SETTING: Infertility care centers. PATIENT(S): Male partners (18 years and older) from heterosexual couples (female partners aged 18-45 years) seeking fertility treatment were recruited. INTERVENTION(S): Men were randomized 1:1 to receive folic acid (5 mg) and elemental zinc (30 mg) (n = 713) or a matching placebo (n = 757) daily for 6 months. MAIN OUTCOME MEASURE(S): Sperm DNA methylation was analyzed using the EPIC methylation array (Illumina) at 6 months. Differential sperm DNA methylation was assessed at multiple levels (regional, single cytosine phosphate guanine, etc.). We additionally assessed the impact of supplementation on epigenetic age. RESULT(S): No significant differences were identified between the treatment and placebo groups although some trends appeared to be present. To determine if these trends were noteworthy, we implemented various permutations and found that the patterns we identified were no more than would be expected by random chance. CONCLUSION(S): The data presented here strongly suggest that this supplementation regimen is not effective at altering sperm DNA methylation. These data comport well with previous findings from the FAZST study that found no impact of supplementation on basic semen analysis parameters or live birth. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT01857310.


Asunto(s)
Metilación de ADN/efectos de los fármacos , Ácido Fólico/administración & dosificación , Espermatozoides/efectos de los fármacos , Zinc/administración & dosificación , Adolescente , Adulto , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Recién Nacido , Infertilidad Masculina/dietoterapia , Infertilidad Masculina/epidemiología , Infertilidad Masculina/metabolismo , Nacimiento Vivo/epidemiología , Masculino , Persona de Mediana Edad , Embarazo , Índice de Embarazo , Análisis de Semen , Espermatozoides/metabolismo , Estados Unidos/epidemiología , Adulto Joven
13.
Fertil Steril ; 117(2): 326-338, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34674824

RESUMEN

OBJECTIVE: To develop in vitro fertilization (IVF) prediction models to estimate the individualized chance of cumulative live birth at two time points: pretreatment (i.e., before starting the first complete cycle of IVF) and posttreatment (i.e., before starting the second complete cycle of IVF in those couples whose first complete cycle was unsuccessful). DESIGN: Population-based cohort study. SETTING: National data from the Society for Assisted Reproductive Technology (SART) Clinic Outcome Reporting System. PATIENT(S): Based on 88,614 women who commenced IVF treatment using their own eggs and partner's sperm in SART member clinics. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): The pretreatment model estimated the cumulative chance of a live birth over a maximum of three complete cycles of IVF, whereas the posttreatment model did so over the second and third complete cycles. One complete cycle included all fresh and frozen embryo transfers resulting from one episode of ovarian stimulation. We considered the first live birth episode, including singletons and multiple births. RESULT(S): Pretreatment predictors included woman's age (35 years vs. 25 years, adjusted odds ratio 0.69, 95% confidence interval 0.66-0.73) and body mass index (35 kg/m2 vs. 25 kg/m2, adjusted odds ratio 0.75, 95% confidence interval 0.72-0.78). The posttreatment model additionally included the number of eggs from the first complete cycle (15 vs. 9 eggs, adjusted odds ratio 1.10, 95% confidence interval 1.03-1.18). According to the pretreatment model, a nulliparous woman aged 34 years with a body mass index of 23.3 kg/m2, male partner infertility, and an antimüllerian hormone level of 3 ng/mL has a 61.7% chance of having a live birth over her first complete cycle of IVF (and a cumulative chance over three complete cycles of 88.8%). If a live birth is not achieved, according to the posttreatment model, her chance of having a live birth over the second complete cycle 1 year later (age 35 years, number of eggs 7) is 42.9%. The C-statistic for all models was between 0.71 and 0.73. CONCLUSION(S): The focus of previous IVF prediction models based on US data has been cumulative live birth excluding cycles involving frozen embryos. These novel prediction models provide clinically relevant estimates that could help clinicians and couples plan IVF treatment at different points in time.


Asunto(s)
Técnicas de Apoyo para la Decisión , Fertilización In Vitro , Infertilidad/terapia , Hormona Antimülleriana/sangre , Biomarcadores/sangre , Índice de Masa Corporal , Bases de Datos Factuales , Femenino , Fertilidad , Humanos , Infertilidad/diagnóstico , Infertilidad/fisiopatología , Nacimiento Vivo , Masculino , Edad Materna , Paridad , Embarazo , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
14.
Fertil Steril ; 117(1): 42-50, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34674830

RESUMEN

OBJECTIVE: To evaluate similarities and differences in clinical and laboratory practices among high-performing fertility clinics. DESIGN: Cross-sectional questionnaire study of selected programs. SETTING: Academic and private fertility practices performing in vitro fertilization (IVF). PATIENT(S): Not applicable. INTERVENTION(S): A comprehensive survey was conducted of 13 IVF programs performing at least 100 cycles a year and having high cumulative singleton delivery rates for 2 years. MAIN OUTCOME MEASURE(S): Clinical and laboratory IVF practices. RESULT(S): Although many areas of clinical practice varied among top programs, some commonalities were observed. All programs used a combination of follicle-stimulating hormone and luteinizing hormone for IVF stimulation, intramuscular progesterone in frozen embryo transfer cycles, ultrasound-guided embryo transfers, and a required semen analysis before starting the IVF cycle. Common laboratory practices included vitrification of embryos at the blastocyst stage, air quality control with positive air pressure and high-efficiency particulate air filtration, use of incubator gas filters, working on heated microscope stages, and incubating embryos in a low-oxygen environment, most often in benchtop incubators. CONCLUSION(S): Some areas of consistency in clinical and laboratory practices were noted among high-performing IVF programs that are likely contributing to their success. High-performing programs focused on singleton deliveries. As the field of IVF is rapidly evolving, it is imperative that we share best practices in an effort to improve outcomes from all clinics for the good of our patients.


Asunto(s)
Fertilización In Vitro , Pautas de la Práctica en Medicina/estadística & datos numéricos , Índice de Embarazo , Adulto , Estudios Transversales , Femenino , Fertilización In Vitro/historia , Fertilización In Vitro/estadística & datos numéricos , Fertilización In Vitro/tendencias , Historia del Siglo XXI , Humanos , Infertilidad/epidemiología , Infertilidad/terapia , Masculino , Pautas de la Práctica en Medicina/tendencias , Embarazo , Técnicas Reproductivas Asistidas/historia , Técnicas Reproductivas Asistidas/tendencias , Estudios Retrospectivos , Resultado del Tratamiento , Estados Unidos/epidemiología
15.
F S Rep ; 2(3): 314-319, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34553157

RESUMEN

OBJECTIVE: To study the birth rates of normal vs. high responders after dual trigger of final oocyte maturation with gonadotropin-releasing hormone (GnRH) agonist and human chorionic gonadotropin in fresh in vitro fertilization (IVF) cycles in which ovarian stimulation was achieved by a flexible GnRH antagonist protocol. DESIGN: Retrospective cohort study. SETTING: University hospital. PATIENTS: In women <35 years of age, 290 fresh IVF cycles using the dual trigger protocol with day 5 embryo transfers from January 2013 to July 2018 were included. Cycles excluded were those with preimplantation genetic testing, gestational carriers, donor oocytes, and fertility preservation. INTERVENTIONS: IVF with dual trigger. MAIN OUTCOME MEASURES: Clinical pregnancy rate, live birth rate. RESULTS: Comparing normal responders, defined as <30 oocytes retrieved, and high responders, defined as ≥30 oocytes retrieved, the clinical pregnancy rates (67.0% vs. 69.3%, respectively) and live birth rates (60.5% vs. 60.0%, respectively) were not significantly different. No cases of ovarian hyperstimulation syndrome were reported in either group. CONCLUSIONS: Ovarian stimulation by a flexible GnRH antagonist protocol followed by dual trigger yields comparable outcomes between normal and high responders in fresh IVF cycles.

16.
Ecohealth ; 18(2): 169-181, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34508275

RESUMEN

Echinococcus spp. are zoonotic cestode parasites with a worldwide distribution and a complex, two-host life cycle involving carnivore definitive hosts and small mammal or ungulate intermediate hosts. Surveillance for Echinococcus spp. in the Midwestern United States (USA) is rare. Using a mixed-methods approach, we examined Echinococcus infection risks in wildlife and domestic dogs in four Minnesota Tribal Nations. We hypothesized that the spillover of Echinococcus spp. into domestic dogs would vary with the presence or absence of suspected wildlife host species and certain behaviors associated with domestic dog ownership, like feeding wildlife host carcasses or frequency of veterinary care. Among 83 dogs tested, three (3.6%) were positive for Echinococcus spp. Despite low prevalence, pet owner survey and focus group findings indicated that dogs encounter peri-domestic wildlife most often when they roam freely or consume wildlife carcasses. This study demonstrates a need for further research into spillover potential of endemic zoonotic Echinococcus spp. in the Midwest USA.


Asunto(s)
Equinococosis , Echinococcus , Animales , Animales Salvajes/parasitología , Perros , Equinococosis/epidemiología , Equinococosis/veterinaria , Mamíferos , Minnesota/epidemiología , Prevalencia
17.
Fertil Steril ; 115(4): 831-839, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33750621

RESUMEN

The coronavirus disease 2019 pandemic has resulted in many changes in how we interact in society, requiring that we protect ourselves and others from an invisible, airborne enemy called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Until a vaccine is developed, and it reaches high levels of distribution, everyone must continue to be diligent to limit the viral spread. The practice of assisted reproduction during this pandemic presents unique challenges in addition to the risks identified in general clinical care. The established good tissue practices employed in laboratories are not designed to protect gametes and embryos from an airborne virus, particularly one that may be shed by an asymptomatic staff member. Armed with theoretical risks but lacking direct evidence, assisted-reproduction teams must examine every aspect of their practice, identify areas at a risk of exposure to SARS-CoV-2, and develop a mitigation plan. Several professional fertility societies have created guidelines for the best practices in patient care during the coronavirus disease 2019 pandemic. As we learn more about SARS-CoV-2, updates have been issued to help adapt infection-control and -prevention protocols. This review discusses what is currently known about SARS-CoV-2 infection risks in assisted reproductive centers and recommends the implementation of specific mitigation strategies.


Asunto(s)
COVID-19/prevención & control , Personal de Salud/normas , Control de Infecciones/normas , Equipo de Protección Personal/normas , Guías de Práctica Clínica como Asunto/normas , Técnicas Reproductivas Asistidas/normas , COVID-19/epidemiología , COVID-19/transmisión , Humanos , Control de Infecciones/métodos , Medición de Riesgo/métodos , Medición de Riesgo/normas , Síndrome Respiratorio Agudo Grave/epidemiología , Síndrome Respiratorio Agudo Grave/prevención & control , Síndrome Respiratorio Agudo Grave/transmisión
18.
J Virol ; 94(9)2020 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-32102878

RESUMEN

Semen is the primary transmission vehicle for various pathogenic viruses. Initial steps of transmission, including cell attachment and entry, likely occur in the presence of semen. However, the unstable nature of human seminal plasma and its toxic effects on cells in culture limit the ability to study in vitro virus infection and inhibition in this medium. We found that whole semen significantly reduces the potency of antibodies and microbicides that target glycans on the envelope glycoproteins (Envs) of HIV-1. The extraordinarily high concentration of the monosaccharide fructose in semen contributes significantly to the effect by competitively inhibiting the binding of ligands to α1,2-linked mannose residues on Env. Infection and inhibition in whole human seminal plasma are accurately mimicked by a stable synthetic simulant of seminal fluid that we formulated. Our findings indicate that, in addition to the protein content of biological secretions, their small-solute composition impacts the potency of antiviral microbicides and mucosal antibodies.IMPORTANCE Biological secretions allow viruses to spread between individuals. Each type of secretion has a unique composition of proteins, salts, and sugars, which can affect the infectivity potential of the virus and inhibition of this process. Here, we describe HIV-1 infection and inhibition in whole human seminal plasma and a synthetic simulant that we formulated. We discovered that the sugar fructose in semen decreases the activity of a broad and potent class of antiviral agents that target mannose sugars on the envelope protein of HIV-1. This effect of semen fructose likely reduces the efficacy of such inhibitors to prevent the sexual transmission of HIV-1. Our findings suggest that the preclinical evaluation of microbicides and vaccine-elicited antibodies will be improved by their in vitro assessment in synthetic formulations that simulate the effects of semen on HIV-1 infection and inhibition.


Asunto(s)
Fructosa/metabolismo , Fructosa/farmacología , Semen/metabolismo , Adulto , Antiinfecciosos/farmacología , Antivirales/antagonistas & inhibidores , Antivirales/farmacología , Línea Celular Tumoral , Productos del Gen env/metabolismo , Genes env/genética , Células HEK293 , Infecciones por VIH/virología , VIH-1/inmunología , Humanos , Masculino , Manosa/metabolismo , Polisacáridos/inmunología , Polisacáridos/metabolismo , Semen/virología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/metabolismo
19.
J Adolesc Young Adult Oncol ; 9(2): 208-221, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31651207

RESUMEN

Purpose: Fertility preservation before therapy is underutilized for those diagnosed with cancer as an adolescent or young adult (AYA). The purpose of this study was to describe factors impacting utilization of fertility preservation consultations and procedures among AYAs at the University of Iowa Health Care (UIHC). Methods: Patients were identified by the oncology registry at UIHC. Disease site, histology, date of diagnosis, sex, race, ethnicity, insurance, and zip code data were gathered by the registrars. UIHC's electronic medical record was queried for fertility preservation consultation. The Reproductive Endocrinology and Infertility clinical database captured information about patients who underwent fertility preservation. Rural-urban commuting area codes measured rurality. Descriptive statistics and multivariate linear probability models were used to predict the probability of fertility preservation consultation and procedure. Results: From 2008 to 2017, 2932 AYAs were treated for an invasive malignancy at UIHC. Of the 440 (15%) who received a fertility preservation consultation, 156 (5%) underwent a fertility preservation procedure. Multivariate analyses showed that AYAs with public insurance coverage, those diagnosed with central nervous system (CNS) disease or melanoma, and those >30 years old at diagnosis had a significant decrease in the percentage point probability of having a consultation. The percentage point probability of undergoing a procedure was decreased for female patients, those with melanoma or carcinoma, those seen by a pediatric-based provider, and those diagnosed after 25 years of age. Conclusion: This study has important implications for practice and policy, particularly regarding insurance coverage and patient and provider characteristics leading to fertility preservation consultations and procedures for AYAs with cancer.


Asunto(s)
Preservación de la Fertilidad/métodos , Adolescente , Adulto , Femenino , Humanos , Masculino , Estudios Retrospectivos , Adulto Joven
20.
Andrologia ; 51(10): e13407, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31448444

RESUMEN

Although varicoceles are a widely accepted identifiable male factor in infertile couples, the benefit of varicocele repair in improving pregnancy and live birth rates remains uncertain. The Study for Future Families obtained semen and reproductive hormone samples from US men whose partners were currently pregnant. In our analysis cohort of 709 men, a varicocele was detected by clinical examination in 56 (8%) of men. Men with varicocele had smaller left testis, and lower total and total motile sperm counts than men without varicocele. Gonadotropin levels were higher as well in men with varicocele. Interestingly, testosterone levels were also slightly higher in men with varicocele. Despite these differences, there was no difference between the groups in the time to achieve the study pregnancy or percentage of men with a previous pregnancy. We conclude that even in fertile men, varicoceles are associated with some degree of testicular hypofunction. This would support current recommendations to consider varicocele repair in male partners in infertile couples who demonstrate both a varicocele and abnormal semen parameters and after evaluation for treatable female factors.


Asunto(s)
Fertilidad/fisiología , Semen/fisiología , Testículo/fisiopatología , Varicocele/fisiopatología , Adulto , Estudios de Cohortes , Femenino , Gonadotropinas/sangre , Humanos , Masculino , Embarazo , Estudios Prospectivos , Análisis de Semen/normas , Testosterona/sangre , Varicocele/sangre , Varicocele/diagnóstico
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