Stuart Lavery

Natural Selection of Human Embryos: Impaired Decidualization of Endometrium Disables Embryo-Maternal Interactions and Causes Recurrent Pregnancy Loss

Background Recurrent pregnancy loss (RPL), defined as 3 or more consecutive miscarriages, is widely attributed either to repeated chromosomal instability in the conceptus or to uterine factors that are poorly defined. We tested the hypothesis that abnormal cyclic differentiation of endometrial stromal cells (ESCs) into specialized decidual cells predisposes to RPL, based on the observation that this process may not only be indispensable for placenta formation in pregnancy but also for embryo recognition and selection at time of implantation. Methodology/Principal Findings Analysis of mid-secretory endometrial biopsies demonstrated that RPL is associated with decreased expression of the decidual marker prolactin (PRL) but increased levels of prokineticin-1 (PROK1), a cytokine that promotes implantation. These in vivo findings were entirely recapitulated when ESCs were purified from patients with and without a history of RPL and decidualized in culture. In addition to attenuated PRL production and prolonged and enhanced PROK1 expression, RPL was further associated with a complete dysregulation of both markers upon treatment of ESC cultures with human chorionic gonadotropin, a glycoprotein hormone abundantly expressed by the implanting embryo. We postulated that impaired embryo recognition and selection would clinically be associated with increased fecundity, defined by short time-to-pregnancy (TTP) intervals. Woman-based analysis of the mean and mode TTP in a cohort of 560 RPL patients showed that 40% can be considered “superfertile”, defined by a mean TTP of 3 months or less. Conclusions Impaired cyclic decidualization of the endometrium facilitates implantation yet predisposes to subsequent pregnancy failure by disabling natural embryo selection and by disrupting the maternal responses to embryonic signals. These findings suggest a novel pathological pathway that unifies maternal and embryonic causes of RPL.

NATURAL SELECTION OF HUMAN EMBRYOS: DECIDUALIZING ENDOMETRIAL STROMAL CELLS SERVE AS SENSORS OF EMBRYO QUALITY UPON IMPLANTATION

Background Pregnancy is widely viewed as dependent upon an intimate dialogue, mediated by locally secreted factors between a developmentally competent embryo and a receptive endometrium. Reproductive success in humans is however limited, largely because of the high prevalence of chromosomally abnormal preimplantation embryos. Moreover, the transient period of endometrial receptivity in humans uniquely coincides with differentiation of endometrial stromal cells (ESCs) into highly specialized decidual cells, which in the absence of pregnancy invariably triggers menstruation. The role of cyclic decidualization of the endometrium in the implantation process and the nature of the decidual cytokines and growth factors that mediate the crosstalk with the embryo are unknown. Methodology/Principal Findings We employed a human co-culture model, consisting of decidualizing ESCs and single hatched blastocysts, to identify the soluble factors involved in implantation. Over the 3-day co-culture period, approximately 75% of embryos arrested whereas the remainder showed normal development. The levels of 14 implantation factors secreted by the stromal cells were determined by multiplex immunoassay. Surprisingly, the presence of a developing embryo had no significant effect on decidual secretions, apart from a modest reduction in IL-5 levels. In contrast, arresting embryos triggered a strong response, characterized by selective inhibition of IL-1β, -6, -10, -17, -18, eotaxin, and HB-EGF secretion. Co-cultures were repeated with undifferentiated ESCs but none of the secreted cytokines were affected by the presence of a developing or arresting embryo. Conclusions Human ESCs become biosensors of embryo quality upon differentiation into decidual cells. In view of the high incidence of gross chromosomal errors in human preimplantation embryos, cyclic decidualization followed by menstrual shedding may represent a mechanism of natural embryo selection that limits maternal investment in developmentally impaired pregnancies.

The Androgen and Progesterone Receptors Regulate Distinct Gene Networks and Cellular Functions in Decidualizing Endometrium

Progesterone is indispensable for differentiation of human endometrial stromal cells (HESCs) into decidual cells, a process that critically controls embryo implantation. We now show an important role for androgen receptor (AR) signaling in this differentiation process. Decreased posttranslational modification of the AR by small ubiquitin-like modifier (SUMO)-1 in decidualizing cells accounted for increased responsiveness to androgen. By combining small interfering RNA technology with genome-wide expression profiling, we found that AR and progesterone receptor (PR) regulate the expression of distinct decidual gene networks. Ingenuity pathway analysis implicated a preponderance of AR-induced genes in cytoskeletal organization and cell motility, whereas analysis of AR-repressed genes suggested involvement in cell cycle regulation. Functionally, AR depletion prevented differentiation-dependent stress fiber formation and promoted motility and proliferation of decidualizing cells. In comparison, PR depletion perturbed the expression of many more genes, underscoring the importance of this nuclear receptor in diverse cellular functions. However, several PR-dependent genes encode for signaling intermediates, and knockdown of PR, but not AR, compromised activation of WNT/beta-catenin, TGFbeta/SMAD, and signal transducer and activator of transcription (STAT) pathways in decidualizing cells. Thus, the nonredundant function of the AR in decidualizing HESCs, centered on cytoskeletal organization and cell cycle regulation, implies an important role for androgens in modulating fetal-maternal interactions. Moreover, we show that PR regulates HESC differentiation, at least in part, by reprogramming growth factor and cytokine signal transduction.

Deregulation of the serum- and glucocorticoid-inducible kinase SGK1 in the endometrium causes reproductive failure

Infertility and recurrent pregnancy loss (RPL) are prevalent but distinct causes of reproductive failure that often remain unexplained despite extensive investigations. Analysis of midsecretory endometrial samples revealed that SGK1, a kinase involved in epithelial ion transport and cell survival, is upregulated in unexplained infertility, most prominently in the luminal epithelium, but downregulated in the endometrium of women suffering from RPL. To determine the functional importance of these observations, we first expressed a constitutively active SGK1 mutant in the luminal epithelium of the mouse uterus. This prevented expression of certain endometrial receptivity genes, perturbed uterine fluid handling and abolished embryo implantation. By contrast, implantation was unhindered in Sgk1−/− mice, but pregnancy was often complicated by bleeding at the decidual-placental interface and fetal growth retardation and subsequent demise. Compared to wild-type mice, Sgk1−/− mice had gross impairment of pregnancy-dependent induction of genes involved in oxidative stress defenses. Relative SGK1 deficiency was also a hallmark of decidualizing stromal cells from human subjects with RPL and sensitized these cells to oxidative cell death. Thus, depending on the cellular compartment, deregulated SGK1 activity in cycling endometrium interferes with embryo implantation, leading to infertility, or predisposes to pregnancy complications by rendering the feto-maternal interface vulnerable to oxidative damage.

A review of complications following transvaginal oocyte retrieval for in-vitro fertilization

Transvaginal ultrasound guided oocyte retrieval (TVOR) during in vitro fertilization (IVF) treatment was first described in 1985. By virtue of its simplicity and effectiveness, it has gained widespread popularity and has now become the gold standard for IVF therapy. Nevertheless, despite the advantages, the aspiration needle may injure the adjacent pelvic organs and structures leading to serious complications. The most common complications are haemorrhage, trauma and injury of pelvic structures, and pelvic infection. Other complications described include adnexal torsion, rupture of endometriotic cysts, anaesthetic, and even vertebral osteomyelitis. In the last two decades, several reports have described the complications associated with this technique, and tried to address the risk factors and safety issues. However there is wide variation in the way this common procedure is performed, with room for improvement through published guidelines. This article reviews the most common complications reported in literature, summarizes the recommendations made to minimize their occurrence, and raises some of the controversial issues related to the procedure especially that of pelvic infection. Conflict of interest: none

Attitudes to reproductive genetic testing in women who had a positive BRCA test before having children: a qualitative analysis

The scope of conditions for which preimplantation genetic diagnosis (PGD) is licensed has recently been expanded in the United Kingdom to include genetic predisposition to adult-onset cancer. This qualitative interview study explores reproductive decision making, knowledge of and attitudes to reproductive genetic testing (prenatal diagnosis and PGD) with 25 women aged 18–45 years who received a positive BRCA test in the United Kingdom before having children. In this cohort of younger women, BRCA testing was motivated by risk management decisions; for some, BRCA status has affected their later decisions about having children. The perceived severity of hereditary breast/ovarian cancer (HBOC) influences thoughts about passing on the mutation to children and willingness to consider reproductive genetic testing, but most participants do not believe HBOC is a condition for which pregnancy termination is justified. PGD is considered more acceptable and advantageous because it would prevent transmission to future generations, but women have concerns about selecting embryos and the fact that they and affected family members would not have been selected. Women would also be deterred by the need to undergo in vitro fertilisation (IVF) and ovarian stimulation for PGD. Awareness of reproductive testing options was very variable among the cohort. The findings highlight the complexities of reproductive decision making for young women who knowingly carry a BRCA mutation, and the dilemmas inherent to reproductive genetic testing when the condition being tested for also affects a prospective parent. Counselling and psychological support for BRCA-positive women and couples concerning reproductive options are strongly indicated.

Oocyte cryopreservation for social reasons: demographic profile and disposal intentions of UK users

A small number of studies from the USA and Europe have provided some data on the profile and characteristics of women who have undergone oocyte cryopreservation for what has been termed elective, social or non-medical reasons; however, little is known in a UK context about which women are undergoing oocyte cryopreservation or their reproductive intentions and actions after the procedure. Drawing on data from an exploratory study of 23 UK resident women who had undergone social oocyte cryopreservation, the demographic profile of these women, their reproductive intentions and actions are discussed, as well as their attitudes and intentions towards their cryopreserved oocytes should they never require them in treatment. The study found that, at the time of oocyte cryopreservation, women were on average 36.7 years of age, were university educated, with 65% of the sample holding further postgraduate or professional qualifications. Fifty-seven per cent of the participants were in professional employment. All participants identified as heterosexual and 87% were not in a relationship at the time of cryopreserving their oocytes. Most (88%) participants stated that they would donate unwanted oocytes to research or to other women for use in fertility treatment should they never require them.

Efficacy of Kisspeptin-54 to Trigger Oocyte Maturation in Women at High Risk of Ovarian Hyperstimulation Syndrome (OHSS) During In Vitro Fertilization (IVF) Therapy.

Context: In vitro fertilization (IVF) treatment is an effective therapy for infertility, but can result in the potentially life-threatening complication, ovarian hyperstimulation syndrome (OHSS). Objective: This study aimed to investigate whether kisspeptin-54 can be used to effectively and safely trigger oocyte maturation in women undergoing IVF treatment at high risk of developing OHSS. Setting and Design: This was a phase 2, multi-dose, open-label, randomized clinical trial of 60 women at high risk of developing OHSS carried out during 2013–2014 at Hammersmith Hospital IVF unit, London, United Kingdom. Intervention: Following a standard recombinant FSH/GnRH antagonist protocol, patients were randomly assigned to receive a single injection of kisspeptin-54 to trigger oocyte maturation using an adaptive design for dose allocation (3.2 nmol/kg, n = 5; 6.4 nmol/kg, n = 20; 9.6 nmol/kg, n = 15; 12.8 nmol/kg, n = 20). Oocytes were retrieved 36 h after kisspeptin-54 administration, assessed for maturation, and fertilized by intracytoplasmic sperm injection with subsequent transfer of one or two embryos. Women were routinely screened for the development of OHSS. Main Outcome Measure: Oocyte maturation was measured by oocyte yield (percentage of mature oocytes retrieved from follicles ≥ 14 mm on ultrasound). Secondary outcomes include rates of OHSS and pregnancy. Results: Oocyte maturation occurred in 95% of women. Highest oocyte yield (121%) was observed following 12.8 nmol/kg kisspeptin-54, which was +69% (confidence interval, −16–153%) greater than following 3.2 nmol/kg. At all doses of kisspeptin-54, biochemical pregnancy, clinical pregnancy, and live birth rates per transfer (n = 51) were 63, 53, and 45%, respectively. Highest pregnancy rates were observed following 9.6 nmol/kg kisspeptin-54 (85, 77, and 62%, respectively). No woman developed moderate, severe, or critical OHSS. Conclusion: Kisspeptin-54 is a promising approach to effectively and safely trigger oocyte maturation in women undergoing IVF treatment at high risk of developing OHSS.

Reproductive decision-making in young female carriers of a BRCA mutation

STUDY QUESTION How do young women, who were identified as carrying a BRCA gene mutation before they had children, approach reproductive decision-making and what are their attitudes towards reproductive genetic testing? SUMMARY ANSWER Reproductive decision-making within the context of cancer risk is complex and influenced by personal experiences of cancer. Younger women were not concerned with reproductive decision-making at the time of their genetic test; however, the impact on subsequent reproductive decision-making was considerable and left them with unanticipated dilemmas, such as having children who would be at risk of inheriting cancer predisposition, timing risk-reducing surgery and changing perceptions of responsibility. WHAT IS KNOWN ALREADY Individuals carrying gene mutations predisposing to hereditary breast/ovarian cancer have concerns about passing on the gene mutation to children. STUDY DESIGN, SIZE, DURATION Qualitative methodology and thematic analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS Data were collected through semi-structured interviews with 25 women aged 18-45 who had received a positive result for a BRCA1 or BRCA2 gene mutation while childless. MAIN RESULTS AND THE ROLE OF CHANCE Analysis revealed four central themes: (i) the impact of cancer on reproductive decision-making; (ii) motivation for genetic testing; (iii) risk management and timing of planning children; and (iv) optimism for future medical advancements. LIMITATIONS, REASONS FOR CAUTION This study explores the views of female BRCA carriers. Further research should explore the views of couples, men, and include samples with greater ethnic and social diversity. WIDER IMPLICATIONS OF THE FINDINGS This evidence highlights the need for reproductive decision-making to be addressed at the time of pretest genetic counselling. More information should be provided on reproductive options as well as counselling/support to guide womens reproductive decision-making and prenatal testing options at the time they undertake genetic testing. STUDY FUNDING/COMPETING INTEREST(S) This research was supported by Cancer Research UK (Number C1226 A7920) and NIHR support to the Biomedical Research Centre at The Institute of Cancer Research and RMH. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER Not applicable.

What a difference an egg makes

Institute of Reproductive and Developmental Biology, Imperial College London, London, UK (R A Fisher FRCPath, S Abu-Hayyeh PhD); IVF Hammersmith, Imperial College London, Hammersmith Hospital, London, UK (S A Lavery MRCOG, A Carby MBBS); Department of Obstetrics and Gynaecology, Gloucestershire Royal Hospital, Gloucester, UK (R Swingler MRCOG); and Trophoblastic Tumour Screening and Treatment Centre, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London, UK (R A Fisher, Prof N J Sebire FRCPath, Prof M J Seckl FRCP)