Obstetrics and Gynaecology - Research Publications

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    Identification of nine new susceptibility loci for endometrial cancer
    O'Mara, TA ; Glubb, DM ; Amant, F ; Annibali, D ; Ashton, K ; Attia, J ; Auer, PL ; Beckmann, MW ; Black, A ; Bolla, MK ; Brauch, H ; Brenner, H ; Brinton, L ; Buchanan, DD ; Burwinkel, B ; Chang-Claude, J ; Chanock, SJ ; Chen, C ; Chen, MM ; Cheng, THT ; Clarke, CL ; Clendenning, M ; Cook, LS ; Couch, FJ ; Cox, A ; Crous-Bous, M ; Czene, K ; Day, F ; Dennis, J ; Depreeuw, J ; Doherty, JA ; Dork, T ; Dowdy, SC ; Duerst, M ; Ekici, AB ; Fasching, PA ; Fridley, BL ; Friedenreich, CM ; Fritschi, L ; Fung, J ; Garcia-Closas, M ; Gaudet, MM ; Giles, GG ; Goode, EL ; Gorman, M ; Haiman, CA ; Hall, P ; Hankison, SE ; Healey, CS ; Hein, A ; Hillemanns, P ; Hodgson, S ; Hoivik, EA ; Holliday, EG ; Hopper, JL ; Hunter, DJ ; Jones, A ; Krakstad, C ; Kristensen, VN ; Lambrechts, D ; Le Marchand, L ; Liang, X ; Lindblom, A ; Lissowska, J ; Long, J ; Lu, L ; Magliocco, AM ; Martin, L ; McEvoy, M ; Meindl, A ; Michailidou, K ; Milne, RL ; Mints, M ; Montgomery, GW ; Nassir, R ; Olsson, H ; Orlow, I ; Otton, G ; Palles, C ; Perry, JRB ; Peto, J ; Pooler, L ; Prescott, J ; Proietto, T ; Rebbeck, TR ; Risch, HA ; Rogers, PAW ; Ruebner, M ; Runnebaum, I ; Sacerdote, C ; Sarto, GE ; Schumacher, F ; Scott, RJ ; Setiawan, VW ; Shah, M ; Sheng, X ; Shu, X-O ; Southey, MC ; Swerdlow, AJ ; Tham, E ; Trovik, J ; Turman, C ; Tyrer, JP ; Vachon, C ; Vanden Berg, D ; Vanderstichele, A ; Wang, Z ; Webb, PM ; Wentzensen, N ; Werner, HMJ ; Winham, SJ ; Wolk, A ; Xia, L ; Xiang, Y-B ; Yang, HP ; Yu, H ; Zheng, W ; Pharoah, PDP ; Dunning, AM ; Kraft, P ; De Vivo, I ; Tomlinson, I ; Easton, DF ; Spurdle, AB ; Thompson, DJ (NATURE PUBLISHING GROUP, 2018-08-09)
    Endometrial cancer is the most commonly diagnosed cancer of the female reproductive tract in developed countries. Through genome-wide association studies (GWAS), we have previously identified eight risk loci for endometrial cancer. Here, we present an expanded meta-analysis of 12,906 endometrial cancer cases and 108,979 controls (including new genotype data for 5624 cases) and identify nine novel genome-wide significant loci, including a locus on 12q24.12 previously identified by meta-GWAS of endometrial and colorectal cancer. At five loci, expression quantitative trait locus (eQTL) analyses identify candidate causal genes; risk alleles at two of these loci associate with decreased expression of genes, which encode negative regulators of oncogenic signal transduction proteins (SH2B3 (12q24.12) and NF1 (17q11.2)). In summary, this study has doubled the number of known endometrial cancer risk loci and revealed candidate causal genes for future study.
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    Genetic regulation of disease risk and endometrial gene expression highlights potential target genes for endometriosis and polycystic ovarian syndrome
    Fung, JN ; Mortlock, S ; Girling, JE ; Holdsworth-Carson, SJ ; Teh, WT ; Zhu, Z ; Lukowski, SW ; McKinnon, BD ; McRae, A ; Yang, J ; Healey, M ; Powell, JE ; Rogers, PAW ; Montgomery, GW (NATURE PORTFOLIO, 2018-07-30)
    Gene expression varies markedly across the menstrual cycle and expression levels for many genes are under genetic control. We analyzed gene expression and mapped expression quantitative trait loci (eQTLs) in endometrial tissue samples from 229 women and then analyzed the overlap of endometrial eQTL signals with genomic regions associated with endometriosis and other reproductive traits. We observed a total of 45,923 cis-eQTLs for 417 unique genes and 2,968 trans-eQTLs affecting 82 unique genes. Two eQTLs were located in known risk regions for endometriosis including LINC00339 on chromosome 1 and VEZT on chromosome 12 and there was evidence for eQTLs that may be target genes in genomic regions associated with other reproductive diseases. Dynamic changes in expression of individual genes across cycle include alterations in both mean expression and transcriptional silencing. Significant effects of cycle stage on mean expression levels were observed for (2,427/15,262) probes with detectable expression in at least 90% of samples and for (2,877/9,626) probes expressed in some, but not all samples. Pathway analysis supports similar biological control of both altered expression levels and transcriptional silencing. Taken together, these data identify strong genetic effects on genes with diverse functions in human endometrium and provide a platform for better understanding genetic effects on endometrial-related pathologies.
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    World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonisation Project: IV. Tissue collection, processing, and storage in endometriosis research
    Fassbender, A ; Rahmioglu, N ; Vitonis, AF ; Vigano, P ; Giudice, LC ; D'Hooghe, TM ; Hummelshoj, L ; Adamson, GD ; Becker, CM ; Missmer, SA ; Zondervan, KT (ELSEVIER SCIENCE INC, 2014-11)
    OBJECTIVE: To harmonize standard operating procedures (SOPs) and standardize the recording of associated data for collection, processing, and storage of human tissues relevant to endometriosis. DESIGN: An international collaboration involving 34 clinical/academic centers and three industry collaborators from 16 countries on five continents. SETTING: In 2013, two workshops were conducted followed by global consultation, bringing together 54 leaders in endometriosis research and sample processing from around the world. PATIENT(S): None. INTERVENTION(S): Consensus SOPs were based on: 1) systematic comparison of SOPs from 24 global centers collecting tissue samples from women with and without endometriosis on a medium or large scale (publication on >100 cases); 2) literature evidence where available, or consultation with laboratory experts otherwise; and 3) several global consultation rounds. MAIN OUTCOME MEASURE(S): Standard recommended and minimum required SOPs for tissue collection, processing, and storage in endometriosis research. RESULT(S): We developed "recommended standard" and "minimum required" SOPs for the collection, processing, and storage of ectopic and eutopic endometrium, peritoneum, and myometrium, and a biospecimen data collection form necessary for interpretation of sample-derived results. CONCLUSION(S): The EPHect SOPs allow endometriosis research centers to decrease variability in tissue-based results, facilitating between-center comparisons and collaborations. The procedures are also relevant to research into other gynecologic conditions involving endometrium, myometrium, and peritoneum. The consensus SOPs are based on the best available evidence; areas with limited evidence are identified as requiring further pilot studies. The SOPs will be reviewed based on investigator feedback and through systematic triannual follow-up. Updated versions will be made available at: http://endometriosisfoundation.org/ephect.
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    In situ Biological Dose Mapping Estimates the Radiation Burden Delivered to 'Spared' Tissue between Synchrotron X-Ray Microbeam Radiotherapy Tracks
    Rothkamm, K ; Crosbie, JC ; Daley, F ; Bourne, S ; Barber, PR ; Vojnovic, B ; Cann, L ; Rogers, PAW ; Jagetia, GC (PUBLIC LIBRARY SCIENCE, 2012-01-06)
    Microbeam radiation therapy (MRT) using high doses of synchrotron X-rays can destroy tumours in animal models whilst causing little damage to normal tissues. Determining the spatial distribution of radiation doses delivered during MRT at a microscopic scale is a major challenge. Film and semiconductor dosimetry as well as Monte Carlo methods struggle to provide accurate estimates of dose profiles and peak-to-valley dose ratios at the position of the targeted and traversed tissues whose biological responses determine treatment outcome. The purpose of this study was to utilise γ-H2AX immunostaining as a biodosimetric tool that enables in situ biological dose mapping within an irradiated tissue to provide direct biological evidence for the scale of the radiation burden to 'spared' tissue regions between MRT tracks. Γ-H2AX analysis allowed microbeams to be traced and DNA damage foci to be quantified in valleys between beams following MRT treatment of fibroblast cultures and murine skin where foci yields per unit dose were approximately five-fold lower than in fibroblast cultures. Foci levels in cells located in valleys were compared with calibration curves using known broadbeam synchrotron X-ray doses to generate spatial dose profiles and calculate peak-to-valley dose ratios of 30-40 for cell cultures and approximately 60 for murine skin, consistent with the range obtained with conventional dosimetry methods. This biological dose mapping approach could find several applications both in optimising MRT or other radiotherapeutic treatments and in estimating localised doses following accidental radiation exposure using skin punch biopsies.
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    MyD88 and TLR4 Expression in Epithelial Ovarian Cancer
    Block, MS ; Vierkant, RA ; Rambau, PF ; Winham, SJ ; Wagner, P ; Traficante, N ; Toloczko, A ; Tiezzi, DG ; Taran, FA ; Sinn, P ; Sieh, W ; Sharma, R ; Rothstein, JH ; Ramon y Cajal, T ; Paz-Ares, L ; Oszurek, O ; Orsulic, S ; Ness, RB ; Nelson, G ; Modugno, F ; Menkiszak, J ; McGuire, V ; McCauley, BM ; Mack, M ; Lubinski, J ; Longacre, TA ; Li, Z ; Lester, J ; Kennedy, CJ ; Kalli, KR ; Jung, AY ; Johnatty, SE ; Jimenez-Linan, M ; Jensen, A ; Intermaggio, MP ; Hung, J ; Herpel, E ; Hernandez, BY ; Hartkopf, AD ; Harnett, PR ; Ghatage, P ; Garcia-Bueno, JM ; Gao, B ; Fereday, S ; Eilber, U ; Edwards, RP ; de Sousa, CB ; de Andrade, JM ; Chudecka-Glaz, A ; Chenevix-Trench, G ; Cazorla, A ; Brucker, SY ; Alsop, J ; Whittemore, AS ; Steed, H ; Staebler, A ; Moysich, KB ; Menon, U ; Koziak, JM ; Kommoss, S ; Kjaer, SK ; Kelemen, LE ; Karlan, BY ; Huntsman, DG ; Hogdall, E ; Gronwald, J ; Goodman, MT ; Gilks, B ; Jose Garcia, M ; Fasching, PA ; de Fazio, A ; Deen, S ; Chang-Claude, J ; dos Reis, FJC ; Campbell, IG ; Brenton, JD ; Bowtell, DD ; Benitez, J ; Pharoah, PDP ; Kobel, M ; Ramus, SJ ; Goode, EL (ELSEVIER SCIENCE INC, 2018-03)
    OBJECTIVE: To evaluate myeloid differentiation primary response gene 88 (MyD88) and Toll-like receptor 4 (TLR4) expression in relation to clinical features of epithelial ovarian cancer, histologic subtypes, and overall survival. PATIENTS AND METHODS: We conducted centralized immunohistochemical staining, semi-quantitative scoring, and survival analysis in 5263 patients participating in the Ovarian Tumor Tissue Analysis consortium. Patients were diagnosed between January 1, 1978, and December 31, 2014, including 2865 high-grade serous ovarian carcinomas (HGSOCs), with more than 12,000 person-years of follow-up time. Tissue microarrays were stained for MyD88 and TLR4, and staining intensity was classified using a 2-tiered system for each marker (weak vs strong). RESULTS: Expression of MyD88 and TLR4 was similar in all histotypes except clear cell ovarian cancer, which showed reduced expression compared with other histotypes (P<.001 for both). In HGSOC, strong MyD88 expression was modestly associated with shortened overall survival (hazard ratio [HR], 1.13; 95% CI, 1.01-1.26; P=.04) but was also associated with advanced stage (P<.001). The expression of TLR4 was not associated with survival. In low-grade serous ovarian cancer (LGSOC), strong expression of both MyD88 and TLR4 was associated with favorable survival (HR [95% CI], 0.49 [0.29-0.84] and 0.44 [0.21-0.89], respectively; P=.009 and P=.02, respectively). CONCLUSION: Results are consistent with an association between strong MyD88 staining and advanced stage and poorer survival in HGSOC and demonstrate correlation between strong MyD88 and TLR4 staining and improved survival in LGSOC, highlighting the biological differences between the 2 serous histotypes.
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    Genetic regulation of methylation in human endometrium and blood and gene targets for reproductive diseases
    Mortlock, S ; Restuadi, R ; Levien, R ; Girling, JE ; Holdsworth-Carson, SJ ; Healey, M ; Zhu, Z ; Qi, T ; Wu, Y ; Lukowski, SW ; Rogers, PAW ; Yang, J ; McRae, AF ; Fung, JN ; Montgomery, GW (BMC, 2019-03-14)
    BACKGROUND: Major challenges in understanding the functional consequences of genetic risk factors for human disease are which tissues and cell types are affected and the limited availability of suitable tissue. The aim of this study was to evaluate tissue-specific genotype-epigenetic characteristics in DNA samples from both endometrium and blood collected from women at different stages of the menstrual cycle and relate results to genetic risk factors for reproductive traits and diseases. RESULTS: We analysed DNA methylation (DNAm) data from endometrium and blood samples from 66 European women. Methylation profiles were compared between stages of the menstrual cycle, and changes in methylation overlaid with changes in transcription and genotypes. We observed large changes in methylation (27,262 DNAm probes) across the menstrual cycle in endometrium that were not observed in blood. Individual genotype data was tested for association with methylation at 443,016 and 443,101 DNAm probes in endometrium and blood respectively to identify methylation quantitative trait loci (mQTLs). A total of 4546 sentinel cis-mQTLs (P < 1.13 × 10-10) and 434 sentinel trans-mQTLs (P < 2.29 × 10-12) were detected in endometrium and 6615 sentinel cis-mQTLs (P < 1.13 × 10-10) and 590 sentinel trans-mQTLs (P < 2.29 × 10-12) were detected in blood. Following secondary analyses, conducted to test for overlap between mQTLs in the two tissues, we found that 62% of endometrial cis-mQTLs were also observed in blood and the genetic effects between tissues were highly correlated. A number of mQTL SNPs were associated with reproductive traits and diseases, including one mQTL located in a known risk region for endometriosis (near GREB1). CONCLUSIONS: We report novel findings characterising genetic regulation of methylation in endometrium and the association of endometrial mQTLs with endometriosis risk and other reproductive traits and diseases. The high correlation of genetic effects between tissues highlights the potential to exploit the power of large mQTL datasets in endometrial research and identify target genes for functional studies. However, tissue-specific methylation profiles and genetic effects also highlight the importance of also using disease-relevant tissues when investigating molecular mechanisms of disease risk.
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    Vascular endothelial growth factor-D over-expressing tumor cells induce differential effects on uterine vasculature in a mouse model of endometrial cancer
    Girling, JE ; Donoghue, JF ; Lederman, FL ; Cann, LM ; Achen, MG ; Stacker, SA ; Rogers, PAW (BIOMED CENTRAL LTD, 2010-07-08)
    BACKGROUND: It has been hypothesised that increased VEGF-D expression may be an independent prognostic factor for endometrial cancer progression and lymph node metastasis; however, the mechanism by which VEGF-D may promote disease progression in women with endometrial cancer has not been investigated. Our aim was to describe the distribution of lymphatic vessels in mouse uterus and to examine the effect of VEGF-D over-expression on these vessels in a model of endometrial cancer. We hypothesised that VEGF-D over-expression would stimulate growth of new lymphatic vessels into the endometrium, thereby contributing to cancer progression. METHODS: We initially described the distribution of lymphatic vessels (Lyve-1, podoplanin, VEGFR-3) and VEGF-D expression in the mouse uterus during the estrous cycle, early pregnancy and in response to estradiol-17beta and progesterone using immunohistochemistry. We also examined the effects of VEGF-D over-expression on uterine vasculature by inoculating uterine horns in NOD SCID mice with control or VEGF-D-expressing 293EBNA tumor cells. RESULTS: Lymphatic vessels positive for the lymphatic endothelial cell markers Lyve-1, podoplanin and VEGFR-3 profiles were largely restricted to the connective tissue between the myometrial circular and longitudinal muscle layers; very few lymphatic vessel profiles were observed in the endometrium. VEGF-D immunostaining was present in all uterine compartments (epithelium, stroma, myometrium), although expression was generally low. VEGF-D immunoexpression was slightly but significantly higher in estrus relative to diestrus; and in estradiol-17beta treated mice relative to vehicle or progesterone treated mice. The presence of VEGF-D over-expressing tumor cells did not induce endometrial lymphangiogenesis, although changes were observed in existing vessel profiles. For myometrial lymphatic and endometrial blood vessels, the percentage of profiles containing proliferating endothelial cells, and the cross sectional area of vessel profiles were significantly increased in response to VEGF-D in comparison to control tumor cells. In contrast, no significant changes were noted in myometrial blood vessels. In addition, examples of invading cells or tumor emboli were observed in mice receiving VEGF-D expressing 293EBNA cells. CONCLUSIONS: These results illustrate that VEGF-D over-expression has differential effects on the uterine vasculature. These effects may facilitate VEGF-D's ability to promote endometrial cancer metastasis and disease progression.
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    Characterization of Diffuse Intrinsic Pontine Glioma Radiosensitivity using Synchrotron Microbeam Radiotherapy and Conventional Radiation Therapy In Vitro
    Smyth, LM ; Rogers, PAW ; Crosbie, JC ; Donoghue, JF (RADIATION RESEARCH SOC, 2018-02)
    Synchrotron microbeam radiation therapy is a promising preclinical radiotherapy modality that has been proposed as an alternative to conventional radiation therapy for diseases such as diffuse intrinsic pontine glioma (DIPG), a devastating pediatric tumor of the brainstem. The primary goal of this study was to characterize and compare the radiosensitivity of two DIPG cell lines (SF7761 and JHH-DIPG-1) to microbeam and conventional radiation. We hypothesized that these DIPG cell lines would exhibit differential responses to each radiation modality. Single cell suspensions were exposed to microbeam (112, 250, 560, 1,180 Gy peak dose) or conventional (2, 4, 6 and 8 Gy) radiation to produce clonogenic cell-survival curves. Apoptosis induction and the cell cycle were also analyzed five days postirradiation using flow cytometry. JHH-DIPG-1 cells displayed greater radioresistance than SF7761 to both microbeam and conventional radiation, with higher colony formation and increased accumulation of G2/M-phase cells. Apoptosis was significantly increased in SF7761 cells compared to JHH-DIPG-1 after microbeam irradiation, demonstrating cell-line specific differential radiosensitivity to microbeam radiation. Additionally, biologically equivalent doses to microbeam and conventional radiation were calculated based on clonogenic survival, furthering our understanding of the response of cancer cells to these two radiotherapy modalities.
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    Generation of immortalized human endometrial stromal cell lines with different endometriosis risk genotypes
    Holdsworth-Carson, SJ ; Colgrave, EM ; Donoghue, JF ; Fung, JN ; Churchill, ML ; Mortlock, S ; Paiva, P ; Healey, M ; Montgomery, GW ; Girling, JE ; Rogers, PAW (OXFORD UNIV PRESS, 2019-04)
    Endometriotic lesions are composed in part of endometrial-like stromal cells, however, there is a shortage of immortalized human endometrial stromal cultures available for research. As genetic factors play a role in endometriosis risk, it is important that genotype is also incorporated into analysis of pathological mechanisms. Human telomerase reverse transcriptase (hTERT) immortalization (using Lenti-hTERT-green fluorescent protein virus) took place following genotype selection; 13 patients homozygous for either the risk or non-risk 'other' allele for one or more important endometriosis risk single nucleotide polymorphism on chromosome 1p36.12 (rs3820282, rs56318008, rs55938609, rs12037376, rs7521902 or rs12061255). Short tandem repeat DNA profiling validated that donor tissue matched that of the immortalized cell lines and confirmed that cultures were genetically novel. Expression of morphological markers (vimentin and cytokeratin) and key genes of interest (telomerase, estrogen and progesterone receptors and LINC00339) were examined and functional assays for cell proliferation, steroid hormone and inflammatory responses were performed for 7/13 cultures. All endometrial stromal cell lines maintained their fibroblast-like morphology (vimentin-positive) and homozygous endometriosis-risk genotype following introduction of hTERT. Furthermore, the new stromal cultures demonstrated positive and diverse responses to hormones (proliferation and decidualisation changes) and inflammation (dose-dependent response), while maintaining hormone receptor expression. In conclusion, we successfully developed a range of human endometrial stromal cell lines that carry important endometriosis-risk alleles. The wider implications of this approach go beyond advancing endometriosis research; these cell lines will be valuable tools for multiple endometrial pathologies offering a level of genetic and phenotypic diversity not previously available.
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    Endometrial uNK cell counts do not predict successful implantation in an IVF population
    Donoghue, JF ; Paiva, P ; Teh, WT ; Cann, LM ; Nowell, C ; Rees, H ; Bittinger, S ; Obers, V ; Bulmer, JN ; Stern, C ; Mcbain, J ; Rogers, PAW (OXFORD UNIV PRESS, 2019-12)
    STUDY QUESTION: Are uterine natural killer (uNK) cell numbers and their distribution relative to endometrial arterioles altered in women with recurrent implantation failure (RIF) compared to women with embryo implantation success (IS)? SUMMARY ANSWER: uNK cell numbers and their distribution relative to endometrial arterioles are not significantly different in women with RIF compared to women in whom embryo implantation occurs successfully following IVF. WHAT IS ALREADY KNOWN: uNK cells are regulators of decidual angiogenesis and spiral arteriole remodelling during early pregnancy. Although some studies have shown that uNK cell numbers may be altered in women with RIF, the methods used to measure uNK cell numbers have proven inconsistent, making reproduction of these results difficult. It is unclear, therefore, whether the results reported so far are reproducible. Moreover, it is not known how uNK cell numbers may impact IVF outcomes. Despite the lack of conclusive evidence, uNK cell numbers are often evaluated as a prognostic criterion in women undergoing assisted reproductive procedures. STUDY DESIGN, SIZE, DURATION: Endometrial pipelle biopsies were collected 6-8 days post-LH surge in natural cycles from women with RIF (n = 14), women with IS (n = 11) and women with potential RIF at the time of the study (PRIF; n = 9) from 2013 to 2015. PARTICIPANTS/MATERIALS, SETTING, METHODS: uNK cells (i.e. CD56+ and/or CD16+ phenotypes) and their distribution relative to endometrial arterioles were investigated by standard immunohistochemistry protocols and quantified using Aperio ScanScopeXT images digitized by ImageJ and deconvoluted into binary images for single cell quantification using a Gaussian Blur and Yen algorithm. MAIN RESULTS AND THE ROLE OF CHANCE: There was no significant difference in the cell density of CD56+ or CD16+ uNK cells in women with RIF compared to women with IS or PRIF. There was a higher proportion of uNK cells in the distal regions compared to the regions closest to the arterioles in all patient groups. Further, we identified a significant reduction in uNK cell density in women who had a previous pregnancy compared to those who had not, regardless of their current implantation status. LARGE SCALE DATA: Not applicable. LIMITATIONS, REASONS FOR CAUTION: Spiral arterioles could not always be accurately identified by digital image analysis; therefore, all endometrial arterioles were selected and analysed. Patient numbers for the study were low. However, as the clinical phenotypes of each patient were well defined, and endometrial dating was accurately determined by three independent pathologists, differences between patient groups with respect to the uNK numbers and distribution should have been measurable if uNK cell counts were to be useful as a prognostic marker of RIF. WIDER IMPLICATIONS OF THE FINDINGS: Our findings demonstrate that CD56+ and CD16+ uNK cell numbers are not significantly different in women with RIF in a typical cohort of women undergoing IVF. Further, prior pregnancy was associated with a significantly reduced number of uNK cells in both the RIF and IS patient groups, suggestive of a long-term pregnancy induced suppression of uNK cells. Combined, these findings do not support the clinical value of using uNK cell numbers as a prognostic indicator of implantation success with IVF treatment. STUDY FUNDING/COMPETING INTEREST(S): Funding for this work was provided by Royal Women's Hospital Foundation. P.P. was supported by an NHMRC Early Career Fellowship [TF 11/14] and W.T.T. was supported by an NHMRC Postgraduate Scholarship [1055814]. The authors do not have any competing interests with this study.