RESUMEN
In humans, FMR1 (fragile X mental retardation 1) is strongly expressed in granulosa cells (GCs) of the female germline and apparently controls efficiency of folliculogenesis. Major control mechanism(s) of the gene transcription rate seem to be based on the rate of CpG-methylation along the CpG island promoter. Conducting CpG-methylation-specific bisulfite-treated PCR assays and subsequent sequence analyses of both gene alleles, revealed three variably methylated CpG domains (FMR1-VMR (variably methylated region) 1, -2, -3) and one completely unmethylated CpG-region (FMR1-UMR) in this extended FMR1-promoter-region. FMR1-UMR in the core promoter was exclusively present only in female GCs, suggesting expression from both gene alleles, i.e., escaping the female-specific X-inactivation mechanism for the second gene allele. Screening for putative target sites of transcription factors binding with CpG methylation dependence, we identified a target site for the transcriptional activator E2F1 in FMR1-VMR3. Using specific electrophoretic mobility shift assays, we found E2F1 binding efficiency to be dependent on CpG-site methylation in its target sequence. Comparative analysis of these CpGs revealed that CpG 94-methylation in primary GCs of women with normal and reduced efficiency of folliculogenesis statistically significant differences. We therefore conclude that E2F1 binding to FMR1-VMR3 in human GCs is part of an epigenetic mechanism regulating the efficiency of human folliculogenesis. Our data indicate that epigenetic mechanisms may control GC FMR1-expression rates.
Asunto(s)
Metilación de ADN , Epigénesis Genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Células de la Granulosa/metabolismo , Reserva Ovárica , Insuficiencia Ovárica Primaria/metabolismo , Sitios de Unión , Estudios de Casos y Controles , Línea Celular Tumoral , Islas de CpG , Factor de Transcripción E2F1/metabolismo , Femenino , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Humanos , Insuficiencia Ovárica Primaria/genética , Insuficiencia Ovárica Primaria/fisiopatología , Regiones Promotoras Genéticas , Unión Proteica , Transducción de SeñalRESUMEN
We report a unique case of a rare utilization of IVM. This case shows the successful retrieval of immature oocytes followed by in vitro maturation (IVM) for fertility preservation in a patient undergoing chronic progestin contraception. A 24-year-old patient with anaplastic astrocytoma requiring chemotherapy with temozolomide for 12 cycles as soon as possible with wish for fertility preservation while using a long acting etonogestrel birth control implant presented in our unit for fertility preservation in May 2017. The currently used implant should be preserved for further contraception. As the ovaries presented with a high, pco-like, antral follicle count, IVM was offered; the patient agreed. A transvaginal follicular puncture in general anesthesia without any hormonal intervention and IVM of gained oocytes was performed. As the patient actually had no spouse, she decided to freeze unfertilized metaphase II stage oocytes (MII). Thirteen oocytes were obtained, eight of them could be matured and cryopreserved. IVM could be a possibility for fertility preservation in patients with polycystic ovaries when no time is available for stimulation for conventional in vitro fertilization. Even use of continuous progestin application for contraception is no obstacle.
Asunto(s)
Anticonceptivos Femeninos/administración & dosificación , Desogestrel/administración & dosificación , Preservación de la Fertilidad , Técnicas de Maduración In Vitro de los Oocitos , Femenino , Humanos , Adulto JovenRESUMEN
OBJECTIVE: Many approaches try to identify the underlying molecular mechanisms to detect new potential biomarkers for successful artificial reproductive therapies. One factor has been described as a possible regulator of inflammation during implantation: Pentraxin 3 (PTX3), which seems to be essential for female fertility on one hand, but whose overexpression has been described in many obstetric complications based on abnormal placentation on the other hand. Therefore, we investigated if serum levels of PTX3 at the time of embryo transfer differ between women with an ongoing pregnancy compared to those without implantation. METHODS/DESIGN: During in vitro fertilization cycles of 51 patients, PTX3 levels at the time of embryo transfer were compared between patients without implantation (n = 26) and those with ongoing pregnancy (n = 25) using an enzyme-linked immunosorbent assay. Statistical analysis was performed using the Kolmogorov-Smirnov test, Fisher's exact test and Student's t test RESULTS: No significant differences were found concerning possible confounders (patients age, smoking pattern, embryo quality, number of embryos transferred and prior IVF attempts). Patients without implantation presented with significantly higher serum levels of PTX3 at the time of embryo transfer compared to women who became pregnant (0.781 ± 0.074 ng/ml vs. 0.578 ± 0.055 ng/ml, p < 0.05). CONCLUSIONS: PTX3 could present as a possible biomarker for ART success. The main limitation of this pilot study is its small sample size that needs validation with a larger study population.
Asunto(s)
Proteína C-Reactiva/metabolismo , Implantación del Embrión/fisiología , Transferencia de Embrión , Fertilización In Vitro , Componente Amiloide P Sérico/metabolismo , Adulto , Blastocisto , Femenino , Humanos , Infertilidad/terapia , Proyectos Piloto , Embarazo , Índice de Embarazo , Resultado del TratamientoRESUMEN
BACKGROUND: The aim of this study was to compare pregnancy rates in patients undergoing IVF/ICSI with embryo transfer after 4 and 5 days of culture in a closed incubation system with integrated time-lapse imaging. METHODS: Out of n = 2207 in vitro fertilization (IVF)/ intracytoplasmic sperm injection (ICSI) cycles performed between January 2011 and April 2016 at a tertiary referral university hospital, a total of n = 599 IVF/ICSI cycles with prolonged embryo culture in an integrated time-lapse system (EmbryoScope© (Vitrolife)) until day 4 or 5 were retrospectively analyzed with regard to embryo morphology and pregnancy rates. RESULTS: A transfer on day 5 compared to a transfer on day 4 did not result in higher implantation and clinical pregnancy rates (IR 29.4% on day 4 versus 33.0% on day 5, p = 0.310; CPR 45.2% on day 4 versus 45.7% on day 5, p = 1.0). The percentage of ideal embryos transferred on day 4 was comparable to the rate of ideal embryos transferred on day 5 (41.6% versus 44.1%, p = 0.508). However, on day 4 a significantly higher number of embryos was transferred (1.92 on day 4 versus 1.84 on day 5, p = 0.023), which did not result in higher rates of multiple pregnancies. CONCLUSIONS: Pregnancy rates in IVF/ICSI cycles with integrated time-lapse incubation and transfer on day 4 and 5 are comparable. This finding provides the clinician, IVF laboratory and patient with more flexibility. TRIAL REGISTRATION: This study was retrospectively registered by the local ethics committee of the University of Heidelberg on December 19, 2016 (registration number S-649/2016).
Asunto(s)
Técnicas de Cultivo de Embriones , Transferencia de Embrión/métodos , Incubadoras , Infertilidad Femenina/terapia , Índice de Embarazo , Imagen de Lapso de Tiempo , Adulto , Células Cultivadas , Fase de Segmentación del Huevo/citología , Fase de Segmentación del Huevo/fisiología , Técnicas de Cultivo de Embriones/instrumentación , Técnicas de Cultivo de Embriones/métodos , Implantación del Embrión , Transferencia de Embrión/estadística & datos numéricos , Femenino , Fertilización In Vitro , Fetoscopios , Humanos , Infertilidad Femenina/epidemiología , Embarazo , Estudios Retrospectivos , Inyecciones de Esperma Intracitoplasmáticas , Factores de Tiempo , Imagen de Lapso de Tiempo/instrumentación , Imagen de Lapso de Tiempo/métodosRESUMEN
PURPOSE: Natural cycle (NC) IVF/ICSI has proven to be an alternative to conventional IVF/ICSI cycles. METHODS: Within our retrospective, observational study (n = 159) infertile couples underwent (n = 463) cycles of NC-IVF/ICSI from May 2007 until December 2011. Oocyte pick-up was performed within a pure natural cycle excluding any hormonal stimulation except of hCG for ovulation induction. Oocytes were fertilized by IVF/ICSI and embryo transfer took place 2 or 3 days later. In addition, the current literature was analysed concerning pregnancy rates in NC-IVF/ICSI cycles. RESULTS: Oocyte pick-up was performed in n = 463 NC and was successful in n = 342 cases (IVF n = 135, ICSI n = 207). 203 oocytes were fertilized (IVF n = 87, ICSI n = 116, FR 59.4 %) and lead to 192 embryo transfers. Finally, 25 pregnancies were reached (PR 13.0 % per transfer) resulting in four biochemical pregnancies, 7 (33.3 %) miscarriages, one pregnancy of unknown outcome and 13 live births. Within the current literature (n = 27 studies), PR in NC-IVF/ICSI cycles varied between 10.2 and 50 %. CONCLUSIONS: Within our study, pregnancy rates in pure NC-IVF/ICSI remained below 15 %. Although this may be linked to unfavourable preconditions like patients' age >40 years, low ovarian reserve or long duration of infertility, further improvement is necessary to increase pregnancy rates.
Asunto(s)
Fertilización In Vitro/métodos , Ciclo Menstrual , Índice de Embarazo , Aborto Espontáneo , Adulto , Gonadotropina Coriónica/uso terapéutico , Transferencia de Embrión , Femenino , Humanos , Nacimiento Vivo , Persona de Mediana Edad , Inducción de la Ovulación , Embarazo , Sustancias para el Control de la Reproducción/uso terapéutico , Estudios RetrospectivosRESUMEN
BACKGROUND: Climacteric increases the risk of thrombotic events by alteration of plasmatic coagulation. Up to now, less is known about changes in platelet- (PMP) and endothelial cell-derived microparticles (EMP). METHODS: In this prospective study, plasma levels of microparticles (MP) were compared in 21 premenopausal and 19 postmenopausal women. RESULTS: No altered numbers of total MP or EMP were measured within the study groups. However, the plasma values of CD61-exposing MP from platelets/megakaryocytes were higher in premenopausal women (5,364 × 10(6)/l, range 4,384-17,167) as compared to postmenopausal women (3,808 × 10(6)/l, range 2,009-8,850; p = 0.020). This differentiation was also significant for the subgroup of premenopausal women without hormonal contraceptives (5,364 × 10(6)/l, range 4,223-15,916; p = 0.047; n = 15). Furthermore, in premenopausal women, higher plasma levels of PMP exposing CD62P were also present as compared to postmenopausal women (288 × 10(6)/l, range 139-462, vs. 121 × 10(6)/l, range 74-284; p = 0.024). This difference was also true for CD63+ PMP levels (281 × 10(6)/l, range 182-551, vs. 137 × 10(6)/l, range 64-432; p = 0.015). CONCLUSION: Climacteric lowers the level of PMP but has no impact on the number of EMP in women. These data suggest that PMP and EMP do not play a significant role in enhancing the risk of thrombotic events in healthy, postmenopausal women.
Asunto(s)
Plaquetas/metabolismo , Micropartículas Derivadas de Células/metabolismo , Células Endoteliales/metabolismo , Adolescente , Adulto , Climaterio , Femenino , Citometría de Flujo , Humanos , Integrina beta3/metabolismo , Megacariocitos/metabolismo , Selectina-P/metabolismo , Proyectos Piloto , Posmenopausia , Premenopausia , Tetraspanina 30/metabolismo , Adulto JovenRESUMEN
OBJECTIVE: Although some patients may benefit from reduced follicle-stimulating hormone (FSH) application, in-vitro maturation (IVM) belongs to the rare treatment options in assisted reproduction. We summarize our five-year IVM experience. DESIGN: Retrospective, observational study. SETTING: Reproductive Medicine, University Hospital. SAMPLE: 115 patients with polycystic ovary syndrome (PCOS) as well as patients after ovarian hyperstimulation syndrome (OHSS) from February 2005 to December 2009. MATERIAL AND METHODS: Stimulation started between day 3-10 of the menstrual cycle and FSH dosage was 125IU/day over three days. Ovulation was induced on the third day of FSH injection or one day afterwards and oocyte retrieval was performed 33-38 hours later. Oocytes were cultivated for 24 hours in IVM medium. Fertilization was carried out one day after oocyte retrieval and embryo transfer two days afterwards. MAIN OUTCOME MEASURES: Pregnancy rates. RESULTS: 115 patients were included and 215 oocyte retrievals (intracytoplasmic sperm injection: n=125, 59%; in vitro fertilization: n=73, 34.4%) with 177 embryo transfers performed. The main reasons for IVM were: PCOS (71.7%) and OHSS (15.0%). Mean number of oocytes was 8.9/oocyte retrieval with 5.9 (64%) becoming mature, 2.8 (45.1%) being fertilized and 2.1 transferred. Pregnancy rate per transfer was 15.3% (n=27) with 13 live births (7.3%), one intrauterine death (0.6%), four miscarriages (2.3%) and nine biochemical pregnancies (5.1%). In 61 cases, fertilized oocytes were frozen and 32 cryotransfers were performed, resulting in three pregnancies. CONCLUSIONS: Although the pregnancy rate was low, IVM is very convenient for patients due to low FSH dosages and few appointments at low cost.
Asunto(s)
Técnicas de Maduración In Vitro de los Oocitos/métodos , Infertilidad Femenina/terapia , Adulto , Femenino , Humanos , Infertilidad Femenina/etiología , Síndrome de Hiperestimulación Ovárica/complicaciones , Síndrome del Ovario Poliquístico/complicaciones , Embarazo , Resultado del Embarazo , Índice de Embarazo , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
BACKGROUND: IVM was implemented in medically assisted reproduction 25 years ago. IVM does not involve controlled ovarian stimulation (COS) and is mainly indicated in patients with a high risk of ovarian hyperstimulation syndrome, in particular in patients with polycystic ovary syndrome (PCOS); it is also an acknowledged option in fertility protection. However, the in-vitro culture of immature oocytes raises concerns over their developmental potential and the putative impact on children's health. Although an increasing number of studies on obstetric and neonatal outcomes of IVM children and their development have been published in recent years, study designs are difficult to compare, since IVM is used in women with various indications and IVM protocols do not follow the same standards. OBJECTIVE AND RATIONALE: The aim of this systematic review was to evaluate the current evidence from IVM children of an impact of in-vitro culture of immature oocytes. Primary outcome parameters were birthweight and children's development up to the age of 2 years. We also compared pregnancy pathologies and the outcome of IVM children and COS children in relation to maternal indications, in particular PCOS, and to the type of IVM protocols with or without ovulation trigger as the secondary outcome parameters. IVM is an accepted clinical option for many centres; however, a comprehensive analysis of the available data is needed to establish whether the use of human oocytes that are fully matured in vitro is safe for both children and their mothers. SEARCH METHODS: Google Scholar and PubMed were used for identifying peer-reviewed original articles and reviews through January 2020. A total of 191 studies were screened and 16 studies were included in the qualitative synthesis. Studies were stratified according to indications, the use of an ovulation trigger and multiplicity. OUTCOMES: Birthweights of IVM singletons and multiples were comparable to their respective COS controls: birthweights were also similar if the analysis was restricted to mothers with PCOS. IVM children had a comparable birthweight to COS children, irrespective of whether an ovulation trigger was used in IVM cycles or not. The frequency of gestational diabetes (GD) in singleton pregnancies was comparable between IVM and COS, regardless of infertility background. There was also no difference in GD frequency between IVM and COS, if an hCG ovulation trigger in IVM cycles was used or not. Hypertensive disorders in singleton pregnancies of women with PCOS were significantly more frequent after IVM compared to COS, in particular if IVM cycles were performed only with in-vitro matured oocytes. There was no difference in the preterm birth rate of singleton pregnancies between IVM and COS. Preterm birth rates were still similar if only women diagnosed with PCOS were compared and whether an ovulation trigger in IVM was used or not. The malformation rate in IVM children did not differ in COS children versus children after natural conception. At the age of 2 years, IVM singletons showed similar anthropometric and mental development compared to COS children or children from natural conception. WIDER IMPLICATIONS: The higher incidence of hypertensive disorders in IVM pregnancies needs monitoring during pregnancy. Current data on the development of IVM children are encouraging, although the quality of many studies is limited and long-term data beyond 2 years are scarce. Further studies should be based on generally accepted IVM protocols. Studies on long-term outcomes beyond 2 years are needed to search for potential long-time sequelae of IVM.
Asunto(s)
Síndrome del Ovario Poliquístico , Nacimiento Prematuro , Preescolar , Femenino , Humanos , Recién Nacido , Oocitos , Ovulación , Inducción de la Ovulación/métodos , Síndrome del Ovario Poliquístico/complicaciones , Embarazo , Nacimiento Prematuro/etiologíaRESUMEN
In order to improve ART outcome, non-invasive embryo assessment is gaining more and more attention. Therefore, the aim of this study is to determine the consecutive implantation potential via the secretome between blastocysts with or without implantation and to analyse possible interactions between these differentially expressed proteins. In this prospective study, 69 spent culture media from blastocysts transferred at day 5 were collected from patients undergoing IVF/ICSI treatment in a single IVF centre between April 2015 and November 2018 after informed consent and analysed individually. Exclusion criteria were the absence of informed consent, PCOS, endometriosis and maternal age > 42 years. Dependent on the treatment outcome, media were subsequently divided into two groups: from embryos who implanted successfully (n = 37) and from embryos without implantation (n = 32). Ninety-two proteins were measured simultaneously using the proximity extension assay (PEA) technology with the Olink® CVD III panel employing oligonucleotide-labelled antibodies. Statistical analysis was performed using the Kolmogorov-Smirnov test, Student's t test, the Mann-Whitney U test and Fisher's exact test. Media from implanted blastocysts showed significantly higher expression of EPHB4, ALCAM, CSTB, BMH, TIMP4, CCL24, SELE, FAS, JAM-A, PON3, PDGF-A, vWF and PECAM-1 compared with media from blastocysts without subsequent implantation. The highest relative expression change could be demonstrated for PECAM-1 and TIMP4. PECAM-1, SELE and vWF were co-expressed. Especially EPHB 4, SELE, ALCAM, MCP-1, CCL24, FAS, JAM-A and PDGF-A have already been described in early embryonic development and metabolism. Therefore, these proteins together with PECAM-1 indicate possible biomarkers for non-invasive embryo assessment in the future. However, due to the innovative methodology, defining a threshold for the use as biomarkers remains to be assessed.
Asunto(s)
Técnicas de Cultivo de Embriones/métodos , Desarrollo Embrionario/fisiología , Fertilización In Vitro/métodos , Inyecciones de Esperma Intracitoplasmáticas , Adulto , Medios de Cultivo , Transferencia de Embrión/métodos , Femenino , Humanos , Embarazo , Estudios ProspectivosRESUMEN
BACKGROUND: Hereditary Transthyretin-Related Amyloidosis, a clinically heterogeneous autosomal dominant disease caused by pathogenic variants in the TTR gene, is characterized by the deposition of insoluble misfolded protein fibrils. The diagnosis, especially in non-endemic areas, is typically delayed by 4-5 years; a misdiagnosis due to clinical heterogeneity is common. The study objective was to define the prevalence of Hereditary Transthyretin-Related Amyloidosis in patients with polyneuropathy and/or cardiomyopathy of no obvious aetiology. METHOD: A multicenter observational "Epidemiological analysis for the hereditary Transthyretin-Related AMyloidosis"-TRAM study was performed in Germany, Austria, and Switzerland. RESULTS: A total of 5141 participants were recruited by 50 neurologic and 27 cardiologic specialized centres. Genetic analysis demonstrated a 1.1% Hereditary Transthyretin-Related Amyloidosis positivity rate among patients with polyneuropathy and/or cardiomyopathy of not obvious aetiology. Twenty-one various TTR variants (TTR-positive) were identified. Body Mass Index was lower in the TTR-positive patients as an indicator for the involvement of the autonomic nervous system; the age of onset of clinical manifestations was higher in TTR-positive patients. There were no other genotype-phenotype correlations or the prevalence of specific clinical manifestations in TTR-positive patients. CONCLUSIONS: Our data support the fact that Hereditary Transthyretin-Related Amyloidosis is underdiagnosed in polyneuropathy and cardiomyopathy patients. Routine implementation of genetic testing is recommended in patients with unexplained polyneuropathy and/or cardiomyopathy to accelerate the earlier diagnosis and the time-sensitive treatment initiation.KEY MESSAGESMore than 5.000 participants with CM and/or PNP of no obvious aetiology were recruited in the observational "Epidemiological analysis for the hereditary Transthyretin-Related AMyloidosis" TRAM study and screened for pathogenic TTR variants.The study demonstrated >1% of patients with CM and/or PNP of unclear aetiology are positive for a pathogenic TTR variant.Routine genetic testing is recommended in patients with unexplained CM and/or PNP to accelerate the initial diagnosis and timely treatment initiation.
Asunto(s)
Neuropatías Amiloides Familiares/genética , Cardiomiopatías/epidemiología , Polineuropatías/epidemiología , Prealbúmina/genética , Neuropatías Amiloides Familiares/complicaciones , Neuropatías Amiloides Familiares/diagnóstico , Neuropatías Amiloides Familiares/epidemiología , Cardiomiopatías/diagnóstico , Cardiomiopatías/genética , Pruebas Genéticas , Humanos , Polineuropatías/diagnóstico , Polineuropatías/etiologíaRESUMEN
INTRODUCTION: Infertility generally counts as a profound crisis in the lives of couples and as an emotionally stressful experience. For couples undergoing fertility treatment, this is especially true of the waiting period following embryo transfer, which couples say is the most stressful period during treatment. However, at this specific phase, psychosocial counselling is not always available on the spot. The aim of this randomised controlled trial (RCT) study was to test the Positive Adjustment Coping Intervention (PACI), a low-dose, smartphone-supported psychological intervention for women and men undergoing fertility treatment. METHODS AND ANALYSIS: The effectiveness of PACI is tested by means of a prospective two-arm RCT. During the 14-day waiting period between oocyte puncture/oocyte thawing and pregnancy test, participants are randomly assigned to one of the two groups, and both women and men receive daily text messages on their smartphones. One group receives text messages with statements reflecting positive-adjustment coping attitudes, the other group messages containing cognitive distractions. The primary outcome of this study is the reduction of psychosocial burden during the waiting period of reproductive treatment. Furthermore, we want to assess whether there are differences between the interventions in a pre-post assessment. The secondary outcomes are information on perceived effectiveness and practicability of the intervention one month after the waiting period. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Ethics Committee of Heidelberg University Faculty of Medicine (S-074/2017). Study findings are planned for dissemination via peer-reviewed journal articles and at national and international conferences. TRIAL REGISTRATION NUMBER: NCT03118219; Pre-results. PROTOCOL VERSION: Version 2.0 dated 18/02/2019.
Asunto(s)
Adaptación Psicológica , Infertilidad/psicología , Infertilidad/terapia , Teléfono Inteligente , Apoyo Social , Terapia Asistida por Computador , Adolescente , Adulto , Actitud , Terapia de Parejas , Femenino , Fertilización In Vitro/psicología , Alemania , Humanos , Masculino , Satisfacción del Paciente , Embarazo , Estudios Prospectivos , Técnicas Reproductivas Asistidas/psicología , Inyecciones de Esperma Intracitoplasmáticas/psicología , Adulto JovenRESUMEN
OBJECTIVE: To study the impact of in vitro maturation (IVM) on embryonal development with the use of time-lapse imaging. DESIGN: Retrospective case-control study. SETTING: University hospital. PATIENT(S): In total, 294 embryos were cultured after intracytoplasmic sperm injection treatment of three groups: patients with polycystic ovary syndrome (PCOS) and IVM (n = 105; group 1 [G1]), patients after conventional stimulation without PCOS (n = 115; G2) and with PCOS (n = 74; G3). In total, 171 embryos were finally analyzed (57 G1, 65 G2, and 49 G3). INTERVENTION(S): Data of 23 PCOS patients (30 IVM cycles) from January 2012 to July 2015 were matched according to age and number of oocytes to patients after conventional stimulation without PCOS (n = 30; 30 cycles) and with PCOS (n = 16; 19 cycles). Markers of embryo development were analyzed at different time points. Pregnancy rates (PRs) and live birth rates (LBRs) were recorded. MAIN OUTCOME MEASURE(S): Morphokinetic differences in embryo development after IVM compared with conventional stimulation with or without PCOS. RESULT(S): The rate of good-quality embryos was significantly lower in G1. Embryo development in G1 was significantly accelerated to the time of appearance of two pronuclei but slowed down by the time of reaching 6-cell stage and remained slower compared with embryos of G2 and G3. PRs as well as LBRs did not differ significantly among the study groups. CONCLUSION(S): Although growth dynamics of embryos from G1 differ from G2 and G3 and the rate of good-quality embryos was lower in IVM embryos, PRs and LBRs did not differ significantly.