RESUMEN
Obesity is a highly prevalent chronic disease that impacts >40% of reproductive-aged females. The pathophysiology of obesity is complex and can be understood simply as a chronic energy imbalance whereby caloric intake exceeds caloric expenditure with an energy surplus stored in adipose tissue. Obesity may be categorized into degrees of severity as well as different phenotypes on the basis of metabolic health and underlying pathophysiology. Obesity and excess adiposity have a significant impact on fertility and reproductive health, with direct effects on the hypothalamic-pituitary-ovarian axis, the ovary and oocyte, and the endometrium. There are significant adverse pregnancy outcomes related to obesity, and excess weight gain before, during, and after pregnancy that can alter the lifelong risk for metabolically unhealthy obesity. Given the high prevalence and pervasive impact of obesity on reproductive health, there is a need for better and individualized care for reproductive-aged females that considers obesity phenotype, underlying pathophysiology, and effective and sustainable interventions to treat obesity and manage weight gain before, during, and after pregnancy.
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Obesidad , Salud Reproductiva , Humanos , Femenino , Obesidad/fisiopatología , Obesidad/metabolismo , Obesidad/epidemiología , Embarazo , Reproducción/fisiología , Infertilidad Femenina/fisiopatología , Infertilidad Femenina/metabolismo , Infertilidad Femenina/terapia , Infertilidad Femenina/etiología , Infertilidad Femenina/epidemiología , Metabolismo Energético , Fertilidad/fisiología , Factores de Riesgo , Complicaciones del Embarazo/fisiopatología , Complicaciones del Embarazo/metabolismo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/etiología , Complicaciones del Embarazo/terapia , Resultado del Embarazo/epidemiología , Factores de Edad , AdultoRESUMEN
OBJECTIVE: To perform a comprehensive assessment of protamine (P) isoforms and modifications in human sperm with the aim of identifying how P modifications and isoforms are altered in men with reduced sperm motility and low sperm count. DESIGN: Cross-sectional. SETTING: Academic medical center. PATIENTS: A total of 18 men with prior reported pregnancy and normozoospermia (normal sperm), 14 men from couples with infertility and asthenozoospermia (reduced sperm motility), and 24 men from couples with infertility and oligoasthenoteratozoospermia (low sperm count and motility and abnormal sperm morphology). INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Proteomic assessment using both top-down and bottom-up liquid chromatography mass spectrometry (MS) analysis. RESULTS: A total of 13 posttranslational modifications were identified on P1 and P2 using bottom-up MS, including both phosphorylation and methylation. Top-down MS revealed an unmodified and phosphorylated isoform of P1 and the 3 major isoforms of P2, HP2, HP3, and HP4. Protamine 1 phosphorylation was overall higher in men with male factor infertility compared with those with normal semen analysis (40.5% vs. 32.6). There was no difference in P posttranslational modifications or isoforms of P2 in men with normal vs. abnormal fertility. CONCLUSION: Human protamines bear a number of posttranslational modifications, with alterations in P1 phosphorylation noted in the setting of male factor infertility.
RESUMEN
Obesity is a highly prevalent chronic disease with a significant effect on reproductive-age women. The clinical implications of obesity on fertility and pregnancy are well studied citing ovulatory dysfunction, hormonal imbalances, higher miscarriage rates, and increased maternal and neonatal risks. For this reason, many patients with obesity seek reproductive specialists to help build their families. Despite this literature base, the effect of weight loss interventions prior to assisted reproductive technology (ART) is lacking. This review aims to outline the impact of obesity on ART, specifically in vitro fertilization (IVF). Response differences to treatment protocols compared with normal weight counterparts, limitations of access to care, and the mixed results of weight-reduction strategies prior to fertility treatment will be addressed. The known data surrounding benefits of lifestyle modification, pharmacologic therapies, and surgical interventions for obesity prior to IVF are outlined and found to emphasize a need for further research to determine the optimal approach for infertility patients with obesity.
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Aborto Espontáneo , Infertilidad , Embarazo , Recién Nacido , Humanos , Femenino , Obesidad/complicaciones , Obesidad/epidemiología , Obesidad/terapia , Fertilización In Vitro/efectos adversos , Infertilidad/terapia , Fertilidad , Aborto Espontáneo/etiologíaRESUMEN
Conventional dogma presumes that protamine-mediated DNA compaction in sperm is achieved by electrostatic interactions between DNA and the arginine-rich core of protamines. Phylogenetic analysis reveals several non-arginine residues conserved within, but not across species. The significance of these residues and their post-translational modifications are poorly understood. Here, we investigated the role of K49, a rodent-specific lysine residue in protamine 1 (P1) that is acetylated early in spermiogenesis and retained in sperm. In sperm, alanine substitution (P1(K49A)) decreases sperm motility and male fertility-defects that are not rescued by arginine substitution (P1(K49R)). In zygotes, P1(K49A) leads to premature male pronuclear decompaction, altered DNA replication, and embryonic arrest. In vitro, P1(K49A) decreases protamine-DNA binding and alters DNA compaction and decompaction kinetics. Hence, a single amino acid substitution outside the P1 arginine core is sufficient to profoundly alter protein function and developmental outcomes, suggesting that protamine non-arginine residues are essential for reproductive fitness.
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Aminoácidos , Aptitud Genética , Animales , Masculino , Ratones , Aminoácidos/metabolismo , Arginina/metabolismo , Cromatina/metabolismo , ADN/genética , ADN/metabolismo , Filogenia , Protaminas/química , Protaminas/genética , Protaminas/metabolismo , Semen/metabolismo , Motilidad Espermática , EspermatozoidesRESUMEN
Objective: To report a unique case of total fertilization failure (TFF) after in vitro fertilization with intracytoplasmic sperm injection related to homozygous WEE2 gene mutation and summarize the current literature and management of TFF. Design: Case report. Setting: Academic fertility center. Patients: A 25-year-old woman and her 35-year-old partner with a history of near-complete fertilization failure after 2 cycles of in vitro fertilization/intracytoplasmic sperm injection. Interventions: Consultation with medical and commercial genetic testing for WEE2, PLCZ1, and TLE6. Main Outcome Measures: Oocyte fertilization. Results: The patient was homozygous for WEE2 pathogenic variant impacting oocyte activation and resulting in infertility. Conclusions: In the setting of TFF, early consideration should be given to genetic testing to assist couples in clinical decision-making and help limit the financial and emotional burden associated with unsuccessful fertility intervention.
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OBJECTIVE: To compare the proteomic composition of follicular fluid from women with normal weight vs. women with obesity but without a history of polycystic ovary syndrome or known ovarian dysfunction undergoing in vitro fertilization. DESIGN: Cross-sectional. SETTING: Academic medical center. PATIENT(S): Eight women with normal weight and 8 women with obesity undergoing in vitro fertilization and without a history of polycystic ovary syndrome, ovulatory dysfunction, diminished ovarian reserve, or known endometriosis were included in the analysis. INTERVENTION(S): Not applicable. MAIN OUTCOME MEASURE(S): Proteomic assessment using liquid chromatography-mass spectrometry analysis. RESULT(S): The mean age of women with normal weight was similar to that of women with obesity (32.9 vs. 32.6 years, not significant). The mean body mass index of women with normal weight was 21.2 kg/m2 compared with a body mass index of 37.1 kg/m2 in women with obesity. A total of 1,174 proteins were identified with ≥2 peptides present. Twenty-five proteins were found to be significantly altered in the follicular fluid from women with obesity. Of these 25 proteins, 19 were up-regulated and 6 were down-regulated. Notably, C-reactive protein was 11-fold higher in the follicular fluid from women with obesity than in the follicular fluid from women with normal weight. CONCLUSION(S): Obesity is associated with dysregulation at the level of the follicle, including alterations in proteins related to inflammation and metabolism. These include proteins with emerging roles in energy homeostasis and follicular regulation.
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Líquido Folicular , Síndrome del Ovario Poliquístico , Humanos , Femenino , Líquido Folicular/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Proteómica , Estudios Transversales , Fertilización In Vitro , Obesidad/metabolismoRESUMEN
BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) is a rare, but serious, risk of assisted reproductive technologies. In severe cases, patients may present to the emergency department (ED) for assessment, treatment of related complications, and even in-patient admission. Significant effort has been made to reduce the incidence and complications of OHSS; however, it is unknown if these strategies have decreased patient presentation for treatment in the ED. PURPOSE: To assess ED utilization for OHSS over time and to examine admission rates, patient demographics, and charges. METHODS: Retrospective longitudinal study utilizing data from the Nationwide Emergency Department Sample Database and the National ART Surveillance System. All ED visits between 2006 and 2016 with an ICD-9 or -10 diagnosis of OHSS were included. Demographics including age, geographic location, and income quartile and alternative diagnoses, admission rates, overall charges, and number of stimulation cycles annually were assessed. RESULTS: The number of ovarian stimulation cycles steadily increased from 2006 (n = 110,183) to 2016 (n = 157,721), while the number of OHSS-related ED visits remained relatively stable (APC 2.08, p = 0.14). Admission rates for OHSS decreased from 52.7% in 2006 to 33.1% in 2016 (APC -4.43%, p < 0.01). The average charge for OHSS-related ED visits almost doubled from 2006 to 2016 (APC 8.53, p < 0.01) and was significantly higher than charges for non-OHSS-related visits for age-matched controls (p < 0.01). CONCLUSION: Despite an increase in total stimulation cycles, there was no significant change in the estimated number of patients presenting to the ED; however, admission rates significantly declined. These observations suggest a possible shift in the severity and/or management of OHSS during the study period.
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Síndrome de Hiperestimulación Ovárica , Servicio de Urgencia en Hospital , Femenino , Humanos , Estudios Longitudinales , Síndrome de Hiperestimulación Ovárica/epidemiología , Síndrome de Hiperestimulación Ovárica/etiología , Síndrome de Hiperestimulación Ovárica/terapia , Inducción de la Ovulación/efectos adversos , Técnicas Reproductivas Asistidas/efectos adversos , Estudios RetrospectivosRESUMEN
OBJECTIVE: Despite obesity's significant impact on reproduction, its influence on the physiology of the human endometrium is largely understudied. We hypothesized that endometrial proteomic differences exist between obese (OW; body mass index [BMI] ≥30 kg/m2) and normal-weight women (NWW; BMI, 18.5-24.9 kg/m2). DESIGN: Clinical cross-sectional study. SETTING: Academic Medical Center. PATIENT(S): Healthy, normally-cycling, 18 to 40-year-old women (n = 6 OW and n = 6 NWW). MAIN OUTCOME MEASURE(S): Participants underwent screening and midfollicular phase visits. Demographic and anthropometric characteristics, blood samples, ultrasounds, and follicular phase endometrial biopsies were collected. Proteomic analyses of endometrial samples (liquid chromatography-mass spectrometry) were performed. Proteins with ≥2-fold difference and a false discovery rate of <0.1 were considered statistically significant (Benjamini-Hochberg adjustment). RESULT(S): Reproductive hormone levels did not differ between the two groups. Mean BMI, serum leptin concentration, and bioelectrical impedance analysis indices of adiposity were higher in OW than in NWW. Histological examination of the endometrial samples confirmed normal-appearing endometrium in both OW and NWW. A total of 2,930 proteins were detected across all samples, with an average number of proteins per sample of 2,059 ± 482 in NWW and 2,437 ± 187 in OW. A total of 17 proteins were differentially expressed in OW vs. NWW; 2 were more abundant, whereas 15 were underexpressed in OW, including the progesterone receptor. CONCLUSION(S): In this well-phenotyped population of healthy women, obesity was associated with significant endometrial proliferative phase proteomic differences affecting the hormonal and immunologic pathways. These could contribute to an increased risk of menstrual bleeding abnormalities and create an altered environment for future luteinization.
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Fase Folicular , Proteoma , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Proteoma/metabolismo , Proteómica , Estudios Transversales , Endometrio/metabolismo , Obesidad/metabolismoRESUMEN
Unexplained infertility affects about one-third of infertile couples and is defined as the failure to identify the cause of infertility despite extensive evaluation of the male and female partners. Therefore, there is a need for a multiparametric approach to study sperm function. Recently, we developed a Fluorescence-Based Ratiometric Analysis of Sperm Centrioles (FRAC) assay to determine sperm centriole quality. Here, we perform a pilot study of sperm from 10 fertile men and 10 men in couples with unexplained infertility, using three centriolar biomarkers measured at three sperm locations from two sperm fractions, representing high and low sperm quality. We found that FRAC can identify men from couples with unexplained infertility as the likely source of infertility. Higher quality fractions from 10 fertile individuals were the reference population. All 180 studied FRAC values in the 10 fertile individuals fell within the reference population range. Eleven of the 180 studied FRAC values in the 10 infertile patients were outliers beyond the 95% confidence intervals (P = 0.0008). Three men with unexplained infertility had outlier FRAC values in their higher quality sperm fraction, while four had outlier FRAC values in their lower quality sperm fraction (3/10 and 4/10, P = 0.060 and P = 0.025, respectively), suggesting that these four individuals are infertile due, in part, to centriolar defects. We propose that a larger scale study should be performed to determine the ability of FRAC to identify male factor infertility and its potential contribution to sperm multiparametric analysis.
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Centriolos , Infertilidad Masculina , Femenino , Humanos , Masculino , Proyectos Piloto , Semen , EspermatozoidesRESUMEN
There has been a significant increase in the use of assisted reproductive therapies (ARTs) over the past several decades, allowing many couples with infertility to conceive. Despite the achievements in this field, a mounting body of evidence concerning the epigenetic risks associated with ART interventions such as ovarian hormonal stimulation, intracytoplasmic sperm injection (ICSI), and in vitro culture (IVC) of oocytes and embryos has also emerged. Induced development of multiple follicles, the IVC media itself, and extended culture may alter the epigenome of both gametes and embryos, resulting in yet to be fully understood developmental, postnatal, and adult life health consequences. Investigators have attempted to decipher the molecular mechanisms mediating ART-induced epigenetic changes using either human samples or animal models with some success. As research in this field continues to expand, the ethical responsibilities of embryologists and researchers have become critically important. Here, we briefly discuss the ethical aspects of ART research, concentrating on the constraints arising from the perceived 'unnaturalness' of many of these procedures. Secondly, we focus on the bioethics and morality of human embryo research in general and how ethically acceptable model systems may be used to mimic early human embryogenesis. Lastly, we review the 14-day culture limit of human embryos and the notion that this rule could be considered of taken into account using new technologies and cues from animal models. The 'black box' of early post-implantation embryogenesis might be revealed using embryo models. As long as this distinct moral line has been drawn and closely followed, we should not fear scientific growth in embryo research. Although in vitro fertilization (IVF) is ethically acceptable, research with human embryos to improve its success raises serious ethical concerns that are in need of constant revisiting.Glossary index: Moral status: the ascription of obligations and rights to embryos on the basis of sentience; Sentience: the capacity of the developing embryo to experience feelings and sensations, such as the awareness of pain; Ectogenesis: the growth of the embryo in an artificial environment outside the mother's body.
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Bioética , Investigaciones con Embriones , Animales , Fertilización In Vitro , Humanos , Técnicas Reproductivas Asistidas , Inyecciones de Esperma IntracitoplasmáticasRESUMEN
Fallopian tube (FT) homeostasis requires dynamic regulation of heterogeneous cell populations and is disrupted in infertility and ovarian cancer. Here, we applied single-cell RNA-seq to profile 59,738 FT cells from four healthy, pre-menopausal subjects. The resulting cell atlas contains 12 major cell types representing epithelial, stromal, and immune compartments. Re-clustering of epithelial cells identified four ciliated and six non-ciliated secretory epithelial subtypes, two of which represent potential progenitor pools: one leading to mature secretory cells and the other contributing to either ciliated cells or one of the stromal cell types. To understand how FT cell numbers and states change in a disease state, we analyzed 17,798 cells from two hydrosalpinx samples and observed shifts in epithelial and stromal populations and cell-type-specific changes in extracellular matrix and TGF-ß signaling; this underscores fibrosis pathophysiology. This resource is expected to facilitate future studies aimed at expanding understanding of fallopian tube homeostasis in normal development and disease.
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Trompas Uterinas , Neoplasias Ováricas , Células Epiteliales/metabolismo , Trompas Uterinas/metabolismo , Femenino , Humanos , Neoplasias Ováricas/metabolismo , Análisis de la Célula IndividualRESUMEN
OBJECTIVE: To determine the implications of an incidentally noted subchorionic hematoma on pregnancy outcomes in the infertile population. METHODS: Retrospective cohort study at a tertiary care, university-based facility. All patients with intrauterine pregnancy on initial obstetric ultrasound presenting to an infertility clinic between January 2015 and March 2018 (n = 1210), regardless of treatment cycle, were included. Nonviable pregnancies were excluded. The main outcome measured was association between subchorionic hematoma and first trimester miscarriage. RESULTS: The prevalence of subchorionic hematoma was 12.5% (n = 151) and did not differ by type of fertility treatment. There was no association between subchorionic hematoma and first trimester miscarriage; however, among patients with subchorionic hematoma, those who reported both bleeding and cramping had an increased probability of miscarriage compared to those without symptoms (0.62 vs. 0.12, P <0.001). The live birth rate in this sample was 81.3% and there were no statistically significant differences in pregnancy outcomes between those with and without subchorionic hematoma. CONCLUSION: Among an infertile population, there was no increased risk of miscarriage when subchorionic hematoma was seen on early ultrasound; however, when patients noted both vaginal bleeding and cramping, their probability of miscarriage was significantly increased.
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Aborto Espontáneo , Infertilidad , Complicaciones del Embarazo , Femenino , Embarazo , Humanos , Aborto Espontáneo/epidemiología , Aborto Espontáneo/etiología , Estudios Retrospectivos , Primer Trimestre del Embarazo , Resultado del Embarazo/epidemiología , Hemorragia Uterina/etiología , Hemorragia Uterina/complicaciones , Hematoma/diagnóstico por imagen , Hematoma/epidemiologíaRESUMEN
PURPOSE: To report experience designing and establishing a reproductive registry and sample biorepository and to describe initial subject characteristics and biospecimens. METHODS: Beginning in December 2017, patients presenting for reproductive care at the University of Michigan were approached for study enrollment. Following consent, subjects completed detailed reproductive and health questionnaires. A variety of reproductive specimens and tissues were collected and processed for multiple downstream applications. RESULTS: Subject enrollment began in December of 2017. There are currently 1798 subjects enrolled. Female participants report a variety of reproductive disorders. Available samples include semen, sperm, follicular fluid, granulosa cells, immature oocytes, ovarian and uterine tissue, and blood samples. CONCLUSION: We report the successful establishment of a reproductive registry and sample biorepository. Furthermore, we describe methods for collection and storage of a variety of reproductive tissue processed for multiple downstream translational applications.
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Sistema de Registros/estadística & datos numéricos , Reproducción , Manejo de Especímenes/métodos , Bancos de Tejidos/organización & administración , Bancos de Tejidos/estadística & datos numéricos , Investigación Biomédica Traslacional/normas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Asherman syndrome is a reproductive disorder characterized by intrauterine adhesions and amenorrhea, infertility, abnormal placentation, or pregnancy loss. Treatment of Asherman syndrome involves hysteroscopic lysis of adhesions. Many surgeons utilize postoperative measures such as hormone therapy, solid mechanical devices, or barrier gels to prevent recurrent adhesions in this setting. However, there is limited high-quality evidence to support their use. Additional research is needed on the safety and efficacy of these commonly used methods to guide patient care.
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Ginatresia , Histeroscopía/efectos adversos , Adherencias Tisulares/prevención & control , Enfermedades Uterinas/prevención & control , Adulto , Femenino , Humanos , Prevención SecundariaRESUMEN
PURPOSE: Alternations to the paternal epigenome, specifically the components of sperm chromatin, can lead to infertility in humans and potentially transmit aberrant information to the embryo. One key component of sperm chromatin is the post-translational modification of histones (PTMs). We previously identified a comprehensive profile of histone PTMs in normozoospermic sperm; however, only specific histone PTMs have been identified in abnormal sperm by antibody-based approaches and comprehensive changes to histone PTM profiles remain unknown. Here, we investigate if sperm with abnormalities of total motility, progressive motility, and morphology have altered histone PTM profiles compared to normozoospermic sperm samples. METHODS: Discarded semen samples from 31 men with normal or abnormal semen parameters were analyzed for relative abundance of PTMs on histone H3 and H4 by "bottom-up" nano-liquid chromatography-tandem mass spectrometry. RESULTS: Asthenoteratozoospermic samples (abnormal motility, forward progression, and morphology, n = 6) displayed overall decreased H4 acetylation (p = 0.001) as well as alterations in H4K20 (p = 0.003) and H3K9 methylation (p < 0.04) when compared to normozoospermic samples (n = 8). Asthenozoospermic samples (abnormal motility and progression, n = 5) also demonstrated decreased H4 acetylation (p = 0.04) and altered H4K20 (p = 0.005) and H3K9 methylation (p < 0.04). Samples with isolated abnormal progression (n = 6) primarily demonstrated decreased acetylation on H4 (p < 0.02), and teratozoospermic samples (n = 6) appeared similar to normozoospermic samples (n = 8). CONCLUSION: Sperm samples with combined and isolated abnormalities of total motility, progressive motility, and morphology display distinct and altered histone PTM signatures compared to normozoospermic sperm. This provides evidence that alterations in histone PTMs may be important for normal sperm function and fertility.
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Astenozoospermia/genética , Código de Histonas/genética , Infertilidad/genética , Espermatozoides/metabolismo , Adulto , Astenozoospermia/diagnóstico , Astenozoospermia/patología , Cromatina/genética , Epigénesis Genética , Histonas/genética , Humanos , Infertilidad/diagnóstico , Infertilidad/patología , Masculino , Procesamiento Proteico-Postraduccional/genética , Motilidad Espermática/genética , Espermatozoides/crecimiento & desarrolloRESUMEN
PURPOSE: The purpose of this study was to compare baseline characteristics and ovarian stimulation outcomes between patients presenting for medically indicated vs. elective fertility preservation consultation and to determine the impact of the 2013 ASRM guidelines on oocyte cryopreservation on the patient population presenting for fertility preservation consultation. METHODS: Retrospective cohort study conducted at an academic center. Study population included 332 patients presenting for medically indicated fertility preservation consultation and 210 patients presenting for elective consultation. RESULTS: Patients presenting for elective fertility preservation consultation were more likely to be of advanced age, non-Caucasian, highly educated, single, nulligravid, and meet criteria for diminished ovarian reserve (DOR). Additionally, patients presenting electively were more likely to have fertility insurance benefits. A higher percentage of patients with insurance benefits for oocyte cryopreservation proceeded to stimulation. There were no differences in stimulation parameters or number of retrieved oocytes between the groups when adjusted for age. Following release of the ASRM guidelines on oocyte cryopreservation, there was no difference in the percentage of patients in the medical group who proceeded with stimulation; however, a higher percentage of patients presenting electively underwent ovarian stimulation. CONCLUSION: Although the populations presenting for medical compared with elective fertility preservation differ at baseline, ovarian stimulation parameters and outcomes are similar when adjusted for age. Insurance benefits for fertility preservation are not comprehensive and impact the decision to proceed with stimulation in all patients. The publication of the ASRM guidelines on oocyte cryopreservation increased utilization of this technology among patients presenting electively; however, they remained at an advanced age and with decreased ovarian reserve parameters.
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Criopreservación/métodos , Preservación de la Fertilidad/métodos , Oocitos , Adulto , Femenino , Humanos , Recuperación del Oocito/métodos , Inducción de la Ovulación , Adulto JovenRESUMEN
BACKGROUND: During the process of spermatogenesis, male germ cells undergo dramatic chromatin reorganization, whereby most histones are replaced by protamines, as part of the pathway to compact the genome into the small nuclear volume of the sperm head. Remarkably, approximately 90 % (human) to 95 % (mouse) of histones are evicted during the process. An intriguing hypothesis is that post-translational modifications (PTMs) decorating histones play a critical role in epigenetic regulation of spermatogenesis and embryonic development following fertilization. Although a number of specific histone PTMs have been individually studied during spermatogenesis and in mature mouse and human sperm, to date, there is a paucity of comprehensive identification of histone PTMs and their dynamics during this process. RESULTS: Here we report systematic investigation of sperm histone PTMs and their dynamics during spermatogenesis. We utilized "bottom-up" nanoliquid chromatography-tandem mass spectrometry (nano-LC-MS/MS) to identify histone PTMs and to determine their relative abundance in distinct stages of mouse spermatogenesis (meiotic, round spermatids, elongating/condensing spermatids, and mature sperm) and in human sperm. We detected peptides and histone PTMs from all four canonical histones (H2A, H2B, H3, and H4), the linker histone H1, and multiple histone isoforms of H1, H2A, H2B, and H3 in cells from all stages of mouse spermatogenesis and in mouse sperm. We found strong conservation of histone PTMs for histone H3 and H4 between mouse and human sperm; however, little conservation was observed between H1, H2A, and H2B. Importantly, across eight individual normozoospermic human semen samples, little variation was observed in the relative abundance of nearly all histone PTMs. CONCLUSION: In summary, we report the first comprehensive and unbiased analysis of histone PTMs at multiple time points during mouse spermatogenesis and in mature mouse and human sperm. Furthermore, our results suggest a largely uniform histone PTM signature in sperm from individual humans.
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BACKGROUND: The purpose of this study is to assess predictors of inadequate endometrial cavity thickness (ECT), defined as < 8 mm, in frozen embryo transfer (FET) cycles. METHODS: This is a retrospective cross-sectional study at an academic fertility center including 274 women who underwent their first endometrial preparation with estradiol for autologous FET in our center from 2001-2009. Multivariable logistic regression was performed to determine predictors of inadequate endometrial development in FET cycles. RESULTS: Neither age nor duration of estrogen supplementation were associated with FET endometrial thickness. Lower body mass index, nulliparity, previous operative hysteroscopy and thinner fresh cycle endometrial lining were associated with inadequate endometrial thickness in FET cycles. A maximum thickness of 11.5 mm in a fresh cycle was 80% sensitive and 70% specific for inadequate frozen cycle thickness. CONCLUSIONS: Previous fresh cycle endometrial cavity thickness is associated with subsequent FET cycle endometrial cavity thickness. Women with a fresh cycle thickness of 11.5 mm or less may require additional intervention to achieve adequate endometrial thickness in preparation for a frozen cycle.