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1.
Chimia (Aarau) ; 78(3): 129-134, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38547014

RESUMO

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.
Am J Obstet Gynecol ; 227(2): 129-135, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35150636

RESUMO

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.


Assuntos
Recém-Nascido de Baixo Peso , Nascimento Prematuro , Acetaminofen , Aspirina , Feminino , Fertilização in vitro , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Vigilância da População , Gravidez , Resultado da Gravidez , Gravidez Múltipla , Gravidez de Gêmeos , Nascimento Prematuro/epidemiologia , Técnicas de Reprodução Assistida , Estados Unidos/epidemiologia
3.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32102878

RESUMO

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.


Assuntos
Frutose/metabolismo , Frutose/farmacologia , Sêmen/metabolismo , Adulto , Anti-Infecciosos/farmacologia , Antivirais/antagonistas & inibidores , Antivirais/farmacologia , Linhagem Celular Tumoral , Produtos do Gene env/metabolismo , Genes env/genética , Células HEK293 , Infecções por HIV/virologia , HIV-1/imunologia , Humanos , Masculino , Manose/metabolismo , Polissacarídeos/imunologia , Polissacarídeos/metabolismo , Sêmen/virologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
4.
Andrologia ; 51(10): e13407, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31448444

RESUMO

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.


Assuntos
Fertilidade/fisiologia , Sêmen/fisiologia , Testículo/fisiopatologia , Varicocele/fisiopatologia , Adulto , Estudos de Coortes , Feminino , Gonadotropinas/sangue , Humanos , Masculino , Gravidez , Estudos Prospectivos , Análise do Sêmen/normas , Testosterona/sangue , Varicocele/sangue , Varicocele/diagnóstico
5.
J Assist Reprod Genet ; 36(1): 121-138, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30328574

RESUMO

PURPOSE: To evaluate the risk of prematurity and infant mortality by maternal fertility status, and for in vitro fertilization (IVF) pregnancies, by oocyte source and embryo state combinations. METHODS: Women in 14 States who had IVF-conceived live births during 2004-13 were linked to their infant's birth and death certificates; a 10:1 sample of non-IVF births was selected for comparison; those with an indication of infertility treatment on the birth certificate were categorized as subfertile, all others were categorized as fertile. Risks were modeled separately for the fertile/subfertile/IVF (autologous-fresh only) group and for the IVF group by oocyte source-embryo state combinations, using logistic regression, and reported as adjusted odds ratios (AORs) and 95% confidence intervals (CI). RESULTS: The study population included 2,474,195 pregnancies. Placental complications (placenta previa, abruptio placenta, and other excessive bleeding) and prematurity were both increased with pregestational and gestational diabetes and hypertension, among subfertile and IVF groups, and in IVF pregnancies using donor oocytes. Both subfertile and IVF pregnancies were at risk for prematurity and NICU admission; IVF infants were also at risk for small-for-gestation birthweight, and subfertile infants had greater risks for neonatal and infant death. Within the IVF group, pregnancies with donor oocytes and/or thawed embryos were at greater risk of large-for-gestation birthweight, and pregnancies with thawed embryos were at greater risk of neonatal and infant death. CONCLUSIONS: Prematurity was associated with placental complications, diabetes and hypertension, subfertility and IVF groups, and in IVF pregnancies, donor oocytes and/or thawed embryos.


Assuntos
Fertilidade , Fertilização in vitro/efeitos adversos , Doenças do Recém-Nascido/mortalidade , Infertilidade/complicações , Doenças Placentárias/mortalidade , Nascimento Prematuro/epidemiologia , Adolescente , Adulto , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Idade Materna , Doenças Placentárias/epidemiologia , Gravidez , Gravidez Múltipla , Fatores de Risco , Estados Unidos/epidemiologia , Adulto Jovem
6.
Hum Reprod ; 32(7): 1402-1409, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472321

RESUMO

STUDY QUESTION: Do live birth rates (LBRs) differ between fresh embryo transfer (fresh ET) cycles and their subsequent paired frozen ET (FET) cycles, when comparing cycles based on the total FSH dose used during the fresh cycle? SUMMARY ANSWER: When compared to the paired frozen embryo transfer cycles, the LBR in the fresh cycle of the highest total FSH dose group (>2500 IU) was reduced by 38%. WHAT IS KNOWN ALREADY: There may be a negative association with high gonadotropin doses and LBR after fresh ET. It is unknown whether a similar effect is seen in FET cycles, which are done with increasing frequency. STUDY DESIGN, SIZE, DURATION: In this retrospective observational paired study, we studied IVF cycles between 10 January 2005 and 19 September 2015, for all patients who underwent a fresh, autologous IVF cycle that resulted in at least one fresh ET and at least one FET. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study included 862 women, treated in our academic medical centre, who underwent 935 fresh ET and 1274 FET cycles. Cycles were allocated into three groups based on the total gonadotropin dose they received during their fresh IVF cycle: Group 1 (≤1800 IU FSH), Group 2 (1801-2500 IU), Group 3 (>2500 IU). The primary outcome was LBR after fresh ET and its subsequent paired FET(s), as well as LBR among fresh ETs and FETs as independent samples, based on the total FSH dose used. Implantation rates obtained from fresh and FET cycles were also compared. MAIN RESULTS AND THE ROLE OF CHANCE: The unadjusted fresh LBR was similar between Groups 1 and 2 (46.0% [95% CI: 40.4-51.6] versus 43.8% [38.3-49.4], respectively) but significantly lower in Group 3 (34.4% [29.5-39.8]). The unadjusted frozen transfer LBR was similar among all groups (51.4% [46.7-56.1] versus 46.3% [41.3-51.4] versus 47.5% [42.5-52.4], respectively). When logistic regression analysis with generalized estimating equations was used to control for confounders, the adjusted LBR was found to be similar between the groups both for fresh (odds ratio [OR] = 0.97 [95% CI: 0.61-1.56] Group 2 versus Group 1, OR = 0.69 [0.39-1.21] Group 3 versus Group 1) and FET cycles (OR = 0.87 [0.58-1.31] Group 2 versus Group 1, OR = 0.95 [0.58-1.55] Group 3 versus Group 1). However, for Group 3, the adjusted fresh LBR was 38% lower than its subsequent frozen transfer LBR (OR = 0.62 [0.41-0.93]); this was a statistically significant difference, which was not observed in Group 1 (OR = 0.85 [0.56-1.27]) or Group 2 (OR = 0.95 [0.64-1.41]). LIMITATIONS, REASONS FOR CAUTION: This study is a retrospective cohort, with all of the associated inherent biases. WIDER IMPLICATIONS OF THE FINDINGS: Fresh LBR is negatively impacted by a high dose of total FSH used, as compared to the LBR in subsequent paired FET cycles. Frozen transfer LBR seems unaffected by the total FSH dose used in the fresh cycle, suggesting that the endometrium may be adversely affected, probably indirectly, by high dose gonadotropin use in the fresh IVF cycle only. STUDY FUNDING/COMPETING INTEREST(S): No funding source was used for the completion of this project. There are no conflicts of interest.


Assuntos
Transferência Embrionária/efeitos adversos , Fármacos para a Fertilidade Feminina/administração & dosagem , Hormônio Foliculoestimulante Humano/administração & dosagem , Infertilidade Feminina/terapia , Indução da Ovulação/efeitos adversos , Centros Médicos Acadêmicos , Adulto , Coeficiente de Natalidade , Estudos de Coortes , Criopreservação , Relação Dose-Resposta a Droga , Feminino , Fármacos para a Fertilidade Feminina/efeitos adversos , Fármacos para a Fertilidade Feminina/uso terapêutico , Fertilização in vitro/efeitos adversos , Hormônio Foliculoestimulante Humano/efeitos adversos , Hormônio Foliculoestimulante Humano/genética , Hormônio Foliculoestimulante Humano/uso terapêutico , Humanos , Iowa/epidemiologia , Gravidez , Taxa de Gravidez , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Reprodutibilidade dos Testes , Estudos Retrospectivos
8.
J Assist Reprod Genet ; 33(8): 1017-25, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27241529

RESUMO

PURPOSE: The aim of this study was to determine which genes and gene pathways are differentially expressed when comparing human blastocysts with cleavage-stage embryos. METHODS: We individually assessed gene expression in preimplantation human embryos at cleavage (n = 3) and blastocyst (n = 3) stages. Gene expression patterns were then validated in publically available datasets and then independently validated in vitro with additional human embryos using TaqMan gene expression assays. Immunolocalization studies were conducted to identify protein expression in intact blastocyst-stage embryos. RESULTS: Compared to cleavage-stage embryos, blastocyst-stage embryos differentially expressed 51 genes (p < 0.001), with overrepresentation in amoebiasis pathways and pathways in cancer. Of these 51 genes, 21 were found to be independently validated in a separate, publically available dataset, with a substantial agreement with our initial findings (κ = 0.8). In an independent set of cleavage- and blastocyst-stage embryos, we validated that six of eight tested genes were differentially expressed (p < 0.05) by RT-qPCR. Immunofluorescence studies documented the presence of two studied proteins in the trophectoderm of blastocyst-stage embryos. CONCLUSIONS: Differentially expressed genes may be implicated in the invasion and proliferation of the early embryo. Our research highlights specific genes that may be further studied for their role in the implantation process and additionally raises questions about localized gene and/or protein expression in the trophectoderm, which could affect protocols for, and interpretation of, trophectoderm biopsies performed in in vitro fertilization cycles.


Assuntos
Blastocisto/metabolismo , Proliferação de Células/genética , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Ligação ao Cálcio/genética , Implantação do Embrião/genética , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas S100/genética
9.
J Assist Reprod Genet ; 32(7): 1009-17, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26003657

RESUMO

PURPOSE: To assess human fertilization and preimplantation embryo development in the presence and in the absence of carbon filtration METHODS: This is a retrospective cohort analysis of fresh, controlled ovarian hyperstimulation cycles as well as previously cryopreserved pronuclear stage embryo transfer cycles in a single IVF center. Embryo development and cycle-based outcomes were compared among three groups: 1) when carbon filtration was present, 2) when carbon filtration was absent, and 3) when carbon filtration had been restored. RESULTS: A total of 524 fresh cycles and 156 cryopreserved embryo cycles were analyzed. Fertilization, cleavage, and blastocyst conversion rates for fresh cycles all declined during the period of absent carbon filtration and recovered after the restoration of carbon filtration. Cryopreserved embryos that were thawed and cultured during the period of absent filtration did not have changes in cleavage or blastocyst conversion rates compared to periods where carbon filtration was present. Clinical pregnancy and live birth rates were unchanged among the three time periods. CONCLUSIONS: The absence of carbon filtration in an IVF laboratory air handler is associated with poor fertilization and early embryo development for fresh cycles. Because development of previously frozen pronuclear stage embryos was unaffected, the lack of carbon filtration may preferentially affect embryos in the peri-fertilization period. Carbon filtration is an integral part to a successful human in-vitro fertilization laboratory.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Blastocisto/fisiologia , Carbono , Fertilização in vitro , Resultado da Gravidez , Adulto , Blastocisto/citologia , Estudos de Coortes , Criopreservação/métodos , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário , Feminino , Filtração , Humanos , Recém-Nascido , Laboratórios/normas , Masculino , Indução da Ovulação , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
10.
Hum Reprod ; 29(8): 1801-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24893607

RESUMO

STUDY QUESTION: Is there an association between alcohol intake and semen quality and serum reproductive hormones among healthy men from the USA and Europe? SUMMARY ANSWER: Moderate alcohol intake is not adversely associated with semen quality in healthy men, whereas it was associated with higher serum testosterone levels. WHAT IS KNOWN ALREADY: High alcohol intake has been associated with a wide range of diseases. However, few studies have examined the correlation between alcohol and reproductive function and most have been conducted in selected populations of infertile men or have a small sample size and the results have been contradictory. STUDY DESIGN, SIZE, DURATION: A coordinated international cross-sectional study among 8344 healthy men. A total of 1872 fertile men aged 18-45 years (with pregnant partners) from four European cities and four US states, and 6472 young men (most with unknown fertility) aged 18-28 years from the general population in six European countries were recruited. PARTICIPANTS/MATERIALS, SETTING, METHODS: The men were recruited using standardized protocols. A semen analysis was performed and men completed a questionnaire on health and lifestyle, including their intake of beer, wine and liquor during the week prior to their visit. Semen quality (semen volume, sperm concentration, percentage motile and morphologically normal sperm) and serum reproductive hormones (FSH, LH, testosterone, sex hormone-binding globulin, and inhibin B and free testosterone) were examined. MAIN RESULTS AND THE ROLE OF CHANCE: The participation rate for our populations was 20-30%. We found no consistent association between any semen variable and alcohol consumption, which was low/moderate in this group (median weekly intake 8 units), either for total consumption or consumption by type of alcohol. However, we found a linear association between total alcohol consumption and total or free testosterone in both groups of men. Young and fertile men who consumed >20 units of alcohol per week had, respectively, 24.6 pmol/l (95% confidence interval 16.3-32.9) and 19.7 pmol/l (7.1-32.2) higher free testosterone than men with a weekly intake between 1 and 10 units. Alcohol intake was not significantly associated with serum inhibin B, FSH or LH levels in either group of men. The study is the largest of its kind and has sufficient power to detect changes in semen quality and reproductive hormones. LIMITATIONS, REASONS FOR CAUTION: The participation rate was low, but higher than in most previous semen quality studies. In addition, the study was cross-sectional and the men were asked to recall their alcohol intake in the previous week, which was used as a marker of intake up to 3 months before. If consumption in that week differed from the typical weekly intake and the intake 3 months earlier, misclassification of exposure may have occurred. However, the men were unaware of their semen quality when they responded to the questions about alcohol intake. Furthermore, we cannot exclude that our findings are due to unmeasured confounders, including diet, exercise, stress, occupation and risk-taking behavior. WIDER IMPLICATIONS OF THE FINDINGS: Our study suggests that moderate alcohol intake is not adversely associated with semen quality in healthy men, whereas it was associated with higher serum testosterone levels which may be due to a changed metabolism of testosterone in the liver. Healthy men may therefore be advised that occasional moderate alcohol intake may not harm their reproductive health; we cannot address the risk of high alcohol consumption of longer duration or binge drinking on semen quality and male reproductive hormones. STUDY FUNDING/COMPETING INTERESTS: All funding sources were non-profitable and sponsors of this study played no role in the study design, in data collection, analysis, or interpretation, or in the writing of the article. The authors have no conflicts of interest.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Saúde Reprodutiva , Adulto , Estudos Transversais , Europa (Continente) , Hormônio Foliculoestimulante/metabolismo , Humanos , Inibinas/metabolismo , Hormônio Luteinizante/metabolismo , Masculino , Análise de Regressão , Sêmen/metabolismo , Análise do Sêmen , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/metabolismo , Estados Unidos
11.
J Assist Reprod Genet ; 35(7): 1227-1228, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29974371
12.
Environ Health Perspect ; 131(12): 127015, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38117586

RESUMO

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.


Assuntos
Exposição Materna , Ácidos Ftálicos , Nascimento Prematuro , Feminino , Humanos , Recém-Nascido , Gravidez , Biomarcadores , Etnicidade , Nascimento Prematuro/epidemiologia , Exposição Materna/efeitos adversos , Ácidos Ftálicos/efeitos adversos , Grupos Raciais
13.
J Nurs Manag ; 20(4): 451-60, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22591147

RESUMO

AIM: This paper is a report of a study of differences in nurses' generational psychological empowerment and job satisfaction. BACKGROUND: Generations differ in work styles such as autonomy, work ethics, involvement, views on leadership, and primary views on what constitutes innovation, quality, and service. METHOD: A secondary analysis was conducted from two data sets resulting in a sample of 451 registered nurses employed at five hospitals in West Virginia. One data set was gathered from a convenience sample and one from a randomly selected sample. Data were collected from 2000 to 2004. RESULTS: Baby Boomer nurses reported higher mean total psychological empowerment scores than Generation X nurses. There were no differences in total job satisfaction scores between the generations. CONCLUSION: There were significant differences among the generations' psychological empowerment scores. Generational differences related to psychological empowerment could provide insight into inconsistent findings related to nurse job satisfaction. IMPLICATIONS FOR NURSING MANAGEMENT: Nurse administrators may consider this evidence when working on strategic plans to motivate and entice Generation X nurses and retain Baby Boomers. Although implications based on this study are tentative, the results indicate the need for administrators to consider the differences between Baby Boomer and Generation X nurses.


Assuntos
Atitude do Pessoal de Saúde , Satisfação no Emprego , Recursos Humanos de Enfermagem Hospitalar/psicologia , Poder Psicológico , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Metodológica em Enfermagem , Recursos Humanos de Enfermagem Hospitalar/estatística & dados numéricos
14.
Fertil Steril ; 118(3): 465-472, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35835597

RESUMO

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.


Assuntos
Infertilidade , Injeções de Esperma Intracitoplásmicas , Aneuploidia , Coeficiente de Natalidade , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Infertilidade/diagnóstico , Infertilidade/terapia , Nascido Vivo , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Sêmen , Injeções de Esperma Intracitoplásmicas/efeitos adversos
15.
Fertil Steril ; 118(4): 680-687, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36085173

RESUMO

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.


Assuntos
Aborto Espontâneo , Injeções de Esperma Intracitoplásmicas , Aborto Espontâneo/epidemiologia , Aborto Espontâneo/etiologia , Coeficiente de Natalidade , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Nascido Vivo , Masculino , Recuperação de Oócitos , Oócitos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Sêmen , Injeções de Esperma Intracitoplásmicas/efeitos adversos
16.
J Occup Environ Med ; 64(10): 831-838, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35902368

RESUMO

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.


Assuntos
Herbicidas , Inseticidas , Praguicidas , Humanos , Chumbo , Masculino , Ocupações , Praguicidas/toxicidade , Sêmen , Solventes , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides
17.
Fertil Steril ; 117(4): 803-810, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35216830

RESUMO

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.


Assuntos
Coeficiente de Natalidade , Fertilização in vitro , Estudos de Coortes , Criopreservação , Transferência Embrionária/efeitos adversos , Transferência Embrionária/métodos , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Inseminação , Nascido Vivo , Oócitos , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida , Estudos Retrospectivos
18.
F S Rep ; 3(3): 184-191, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36212571

RESUMO

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.

19.
Fertil Steril ; 117(1): 42-50, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34674830

RESUMO

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.


Assuntos
Fertilização in vitro , Padrões de Prática Médica/estatística & dados numéricos , Taxa de Gravidez , Adulto , Estudos Transversais , Feminino , Fertilização in vitro/história , Fertilização in vitro/estatística & dados numéricos , Fertilização in vitro/tendências , História do Século XXI , Humanos , Infertilidade/epidemiologia , Infertilidade/terapia , Masculino , Padrões de Prática Médica/tendências , Gravidez , Técnicas de Reprodução Assistida/história , Técnicas de Reprodução Assistida/tendências , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos/epidemiologia
20.
Fertil Steril ; 117(2): 326-338, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34674824

RESUMO

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.


Assuntos
Técnicas de Apoio para a Decisão , Fertilização in vitro , Infertilidade/terapia , Hormônio Antimülleriano/sangue , Biomarcadores/sangue , Índice de Massa Corporal , Bases de Dados Factuais , Feminino , Fertilidade , Humanos , Infertilidade/diagnóstico , Infertilidade/fisiopatologia , Nascido Vivo , Masculino , Idade Materna , Paridade , Gravidez , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
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