What is the prognosis for a live birth after unexplained recurrent implantation failure following IVF/ICSI?

STUDY QUESTION: What is the cumulative incidence of live birth and mean time to pregnancy (by conception after IVF/ICSI or natural conception) in women experiencing unexplained recurrent implantation failure (RIF) following IVF/ICSI treatment? SUMMARY ANSWER: In 118 women who had experienced RIF, the reported cumulative incidence of live birth during a maximum of 5.5 years follow-up period was 49%, with a calculated median time to pregnancy leading to live birth of 9 months after diagnosis of RIF. WHAT IS KNOWN ALREADY: Current definitions of RIF include failure to achieve a pregnancy following IVF/ICSI and undergoing three or more fresh embryo transfer procedures of one or two high quality embryos or more than 10 embryos transferred in fresh or frozen cycles. The causes and optimal management of this distressing condition remain uncertain and a range of empirical and often expensive adjuvant therapies is often advocated. Little information is available regarding the long-term prognosis for achieving a pregnancy. STUDY DESIGN, SIZE, DURATION: Two hundred and twenty-three women under 39 years of age who had experienced RIF without a known cause after IVF/ICSI treatment in two tertiary referral university hospitals between January 2008 and December 2012 were invited to participate in this retrospective cohort follow up study. PARTICIPANTS/MATERIALS, SETTING, METHODS: All eligible women were sent a letter requesting their consent to the anonymous use of their medical file data and were asked to complete a questionnaire enquiring about treatments and pregnancies subsequent to experiencing RIF. Medical files and questionnaires were examined and results were analysed to determine the subsequent cumulative incidence of live birth and time to pregnancy within a maximum 5.5 year follow-up period using Kaplan Meier analysis. Clinical predictors for achieving a live birth were investigated using a Cox hazard model. MAIN RESULTS AND THE ROLE OF CHANCE: One hundred and twenty-seven women responded (57%) and data from 118 women (53%) were available for analysis. During the maximum 5.5 year follow up period the overall cumulative incidence of live birth was 49% (95% CI 39-59%). Among women who gave birth, the calculated median time to pregnancy was 9 months after experiencing RIF, where 18% arose from natural conceptions. LIMITATIONS, REASONS FOR CAUTION: Since only 57% of the eligible study cohort completed the questionnaire, the risk of response bias limits the applicability of the study findings. WIDER IMPLICATIONS OF THE FINDINGS: This study reports a favorable overall prognosis for achieving live birth in women who have previously experienced RIF, especially in those who continue with further IVF/ICSI treatments. However since 51% did not achieve a live birth during the follow-up period, there is a need to distinguish those most likely to benefit from further treatment. In this study, no clinical factors were found to be predictive of those achieving a subsequent live birth. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the University Medical Center Utrecht, in Utrecht and the Academic Medical Centre, in Amsterdam. NSM has received consultancy and speaking fees and research funding from Ferring, MSD, Merck Serono, Abbott, IBSA, Gedion Richter, and Clearblue. During the most recent 5-year period BCJMF has received fees or grant support from the following organizations (in alphabetic order); Actavis/Watson/Uteron, Controversies in Obstetrics & Gynecology (COGI), Dutch Heart Foundation, Dutch Medical Research Counsel (ZonMW), Euroscreen/Ogeda, Ferring, London Womens Clinic (LWC), Merck Serono, Myovant, Netherland Genomic Initiative (NGI), OvaScience, Pantharei Bioscience, PregLem/Gedeon Richter/Finox, Reproductive Biomedicine Online (RBMO), Roche, Teva, World Health Organisation (WHO).None of the authors have disclosures to make in relation to this manuscript.

Predicting childhood overweight and obesity using maternal and early life risk factors: a systematic review.

BACKGROUND: Childhood obesity is a serious public health challenge, and identification of high-risk populations with early intervention to prevent its development is a priority. We aimed to systematically review prediction models for childhood overweight/obesity and critically assess the methodology of their development, validation and reporting. METHODS: Medline and Embase were searched systematically for studies describing the development and/or validation of a prediction model/score for overweight and obesity between 1 to 13 years of age. Data were extracted using the Cochrane CHARMS checklist for Prognosis Methods. RESULTS: Ten studies were identified that developed (one), developed and validated (seven) or externally validated an existing (two) prediction model. Six out of eight models were developed using automated variable selection methods. Two studies used multiple imputation to handle missing data. From all studies, 30,475 participants were included. Of 25 predictors, only seven were included in more than one model with maternal body mass index, birthweight and gender the most common. CONCLUSION: Several prediction models exist, but most have not been externally validated or compared with existing models to improve predictive performance. Methodological limitations in model development and validation combined with non-standard reporting restrict the implementation of existing models for the prevention of childhood obesity.

A randomized controlled, non-inferiority trial of modified natural versus artificial cycle for cryo-thawed embryo transfer.

STUDY QUESTION: Are live birth rates (LBRs) after artificial cycle frozen-thawed embryo transfer (AC-FET) non-inferior to LBRs after modified natural cycle frozen-thawed embryo transfer (mNC-FET)? SUMMARY ANSWER: AC-FET is non-inferior to mNC-FET with regard to LBRs, clinical and ongoing pregnancy rates (OPRs) but AC-FET does result in higher cancellation rates. WHAT IS ALREADY KNOWN: Pooling prior retrospective studies of AC-FET and mNC-FET results in comparable pregnancy and LBRs. However, these results have not yet been confirmed by a prospective randomized trial. STUDY DESIGN, SIZE AND DURATION: In this non-inferiority prospective randomized controlled trial (acronym 'ANTARCTICA' trial), conducted from February 2009 to April 2014, 1032 patients were included of which 959 were available for analysis. The primary outcome of the study was live birth. Secondary outcomes were clinical and ongoing pregnancy, cycle cancellation and endometrium thickness. A cost-efficiency analysis was performed. PARTICIPANT/MATERIALS, SETTING, METHODS: This study was conducted in both secondary and tertiary fertility centres in the Netherlands. Patients included in this study had to be 18-40 years old, had to have a regular menstruation cycle between 26 and 35 days and frozen-thawed embryos to be transferred had to derive from one of the first three IVF or IVF-ICSI treatment cycles. Patients with a uterine anomaly, a contraindication for one of the prescribed medications in this study or patients undergoing a donor gamete procedure were excluded from participation. Patients were randomized based on a 1:1 allocation to either one cycle of mNC-FET or AC-FET. All embryos were cryopreserved using a slow-freeze technique. MAIN RESULTS AND THE ROLE OF CHANCE: LBR after mNC-FET was 11.5% (57/495) versus 8.8% in AC-FET (41/464) resulting in an absolute difference in LBR of -0.027 in favour of mNC-FET (95% confidence interval (CI) -0.065-0.012; P = 0.171). Clinical pregnancy occurred in 94/495 (19.0%) patients in mNC-FET versus 75/464 (16.0%) patients in AC-FET (odds ratio (OR) 0.8, 95% CI 0.6-1.1, P = 0.25). 57/495 (11.5%) mNC-FET resulted in ongoing pregnancy versus 45/464 (9.6%) AC-FET (OR 0.7, 95% CI 0.5-1.1, P = 0.15). χ(2) test confirmed the lack of superiority. Significantly more cycles were cancelled in AC-FET (124/464 versus 101/495, OR 1.4, 95% CI 1.1-1.9, P = 0.02). The costs of each of the endometrial preparation methods were comparable (€617.50 per cycle in NC-FET versus €625.73 per cycle in AC-FET, P = 0.54). LIMITATIONS, REASONS FOR CAUTION: The minimum of 1150 patients required for adequate statistical power was not achieved. Moreover, LBRs were lower than anticipated in the sample size calculation. WIDER IMPLICATIONS OF THE FINDINGS: LBRs after AC-FET were not inferior to those achieved by mNC-FET. No significant differences in clinical and OPR were observed. The costs of both treatment approaches were comparable. STUDY FUNDING/COMPETING INTERESTS: An educational grant was received during the conduct of this study. Merck Sharpe Dohme had no influence on the design, execution and analyses of this study. E.R.G. received an education grant by Merck Sharpe Dohme (MSD) during the conduct of the present study. B.J.C. reports grants from MSD during the conduct of the study. A.H. reports grants from MSD and Ferring BV the Netherlands and personal fees from MSD. Grants from ZonMW, the Dutch Organization for Health Research and Development. J.S.E.L. reports grants from Ferring, MSD, Organon, Merck Serono and Schering-Plough during the conduct of the study. F.J.M.B. receives monetary compensation as member of the external advisory board for Merck Serono, consultancy work for Gedeon Richter, educational activities for Ferring BV, research cooperation with Ansh Labs and a strategic cooperation with Roche on automated anti Mullerian hormone assay development. N.S.M. reports receiving monetary compensations for external advisory and speaking work for Ferring BV, MSD, Anecova and Merck Serono during the conduct of the study. All reported competing interests are outside the submitted work. No other relationships or activities that could appear to have influenced the submitted work. TRIAL REGISTRATION NUMBER: Netherlands trial register, number NTR 1586. TRIAL REGISTRATION DATE: 13 January 2009. FIRST PATIENT INCLUDED: 20 April 2009.

The 'Developmental Origins' Hypothesis: relevance to the obstetrician and gynecologist.

The recognition of 'fetal origins of adult disease' has placed new responsibilities on the obstetrician, as antenatal care is no longer simply about ensuring good perinatal outcomes, but also needs to plan for optimal long-term health for mother and baby. Recently, it has become clear that the intrauterine environment has a broad and long-lasting impact, influencing fetal and childhood growth and development as well as future cardiovascular health, non-communicable disease risk and fertility. This article looks specifically at the importance of the developmental origins of ovarian reserve and ageing, the role of the placenta and maternal nutrition before and during pregnancy. It also reviews recent insights in developmental medicine of relevance to the obstetrician, and outlines emerging evidence supporting a proactive clinical approach to optimizing periconceptional as well as antenatal care aimed to protect newborns against long-term disease susceptibility.

Nutritional supplementation and artificial reproductive technique (ART) outcomes.

Approximately one in six couples suffer from subfertility, and many seek treatment with artificial reproductive technologies (ART). Despite improvements in laboratory techniques and ovarian stimulation, ongoing pregnancy rates per cycle remain at ~25%. Couples wanting to improve their chances may turn to adjuvant therapies, such as nutritional supplements. There is growing evidence that periconceptional nutritional status is a key determinant of fertility and long-term health of the offspring, and a lucrative market has developed to meet the demand based on these benefits. However, the practice of routine dietary supplementation before and during IVF treatment has not been subject to well-powered prospective randomised trials. In this article, the potential roles of specific nutritional supplements in the context of improving IVF outcomes are reviewed and an assessment is made of the evidence base supporting their clinical use in this context. Finally, current research needs in the field are outlined.

Ovarian response prediction in GnRH antagonist treatment for IVF using anti-Müllerian hormone.

STUDY QUESTION: What is the clinical value of anti-Müllerian hormone (AMH) for the prediction of high or low ovarian response in controlled ovarian stimulation for IVF using GnRH antagonist treatment? SUMMARY ANSWER: AMH as a single test has substantial accuracy for ovarian response prediction in GnRH antagonist treatment for IVF, with a higher accuracy for predicting a high response than for low response. WHAT IS KNOWN ALREADY: The role of AMH and other patient characteristics in ovarian response prediction has been studied extensively in long GnRH agonist protocols; however, little information is available regarding the clinical value in GnRH antagonists. STUDY DESIGN, SIZE, DURATION: This is an observational (retrospective) substudy as part of an ongoing cohort study. A total of 487 patients scheduled for IVF/ICSI between 2006 and 2011 were included in the study. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients with a regular cycle who underwent their first IVF/ICSI cycle with GnRH antagonist treatment while receiving a starting dose of 150 or 225 IU recombinant FSH were included in the study. Patients were divided into three subgroups according to the following ovarian response categories: high (>15 oocytes or cycle cancellation), normal (4-15 oocytes) and low (<4 oocytes or cycle cancellation). Serum samples collected prior to IVF treatment were used to determine serum AMH levels. MAIN RESULTS AND THE ROLE OF CHANCE: According to the predefined ovarian response categories, 58 patients were classified as high, 326 as normal and 101 as low responders, and the ongoing pregnancy rates did not differ among groups (19.0, 22.1 and 16.8%, respectively, P = 0.9). For the prediction of high response, AMH had an area under the receiver-operating characteristic curve (AUC) of 0.87. Both female age and BMI had lower accuracy (AUC 0.66 and 0.58, respectively). For low response prediction, again AMH had a better accuracy (AUC 0.79) than female age and BMI (AUC 0.59 and 0.56, respectively). In a multivariate model, including the factors age, AMH, BMI, smoking, type and duration of subfertility, only BMI added some predictive value to AMH for both high and low response prediction. Clinical test characteristics demonstrated that using a specificity of ∼90%, the detection rate of AMH for high and low response, corresponding with a test cut-off of 4.5 and 0.8 µg/l, was ∼60 and ∼45%, respectively. LIMITATIONS, REASONS FOR CAUTION: The impact of the antral follicle count (AFC) on ovarian response prediction in GnRH antagonists was not assessed; however, previously studies demonstrated that for GnRH antagonists, AMH has a better accuracy than AFC. WIDER IMPLICATIONS OF THE FINDINGS: The current study demonstrates that AMH is an adequate predictor for both high and low response in GnRH antagonist cycles, showing a similar accuracy to GnRH agonists, as reported previously. The optimization and individualization of GnRH antagonist protocols may be improved by using an AMH-tailored approach. STUDY FUNDING/COMPETING INTERESTS: This study was funded by the Academic Institutional Resources of the Department of Reproductive Medicine of the UMC Utrecht. O.H., M.J.C.E, E.W.G.L and H.L.T. have nothing to declare. N.S.M. has received fees and/or grant support from the following companies (in alphabetic order): Anecova, Ferring, Informa, Merck Serono and MSD. B.C.J.M.F. has received fees and/or grant support from the following companies (in alphabetic order); Childhealth, CVON, Ferring, Ova-Science, PregLem, Roche and Watson laboratories. F.J.B. has received fees and/or grant support from the following companies (in alphabetic order); Merck Serono and MSD. TRIAL REGISTRATION NUMBER: www.clinicaltrials.gov, Protocol ID 13-109.

Environmental and developmental origins of ovarian reserve.

BACKGROUND Oocyte number is established early in life before a gradual loss of this ovarian reserve during reproductive life until oocyte availability becomes limiting at the menopause. Although there is a large genetic component to the ovarian reserve achieved before birth, other influences including the maternal endocrine and nutritional milieu, and environmental factors may represent important developmental determinants. Environmental and nutritional factors may also modify the downward trajectory of ovarian reserve in adult life. The combination of these early and later life influences has the potential to lead to diminished ovarian reserve, compromising fertility in later reproductive years and altering age at natural menopause. METHODS Literature searches of the ISI Web of Knowledge database were carried out using the main terms 'ovarian reserve' and 'menopause AND age' in conjunction with a range of other terms encompassing a variety of factors with potential effects on ovarian reserve. The various searches were inspected manually and the relevant papers selected for critical analysis and interpretation. RESULTS Evidence was identified supporting the view that elevated prenatal androgens have an adverse effect on the early establishment of ovarian reserve, although the implications for ovarian reserve in the polycystic ovary syndrome (which may also be programmed through prenatal androgen exposure) remain uncertain. Recent evidence is cited suggesting that effects of maternal nutrient restriction on ovarian reserve may also involve changes in prenatal androgen exposure. A general rationale is developed through examination of evidence which emphasizes the roles of the aryl hydrocarbon receptor (AHR) and the estrogen receptor (ER) systems in ovarian reserve modulation. Because of their similarity to the natural ligands, many environmental compounds have the ability to bind to these receptors (albeit at lower affinities) and thereby have the potential to influence either the initial setting of ovarian reserve during development or the trajectory of ovarian reserve during adult life. For example, exposure to compounds in cigarette smoke may accelerate loss of ovarian reserve in smokers leading to diminished ovarian reserve, earlier age at last child and earlier menopause. Socioenocomic factors are clearly associated with age at natural menopause, with correlations with economic status and education level. However, such effects in western societies are in general small, and the underlying mechanisms remain unclear. CONCLUSIONS Exposure to many environmental compounds, particularly to those that leach from plastics and other synthetic materials, is commonplace in modern societies to the extent that many are found at measurable concentrations in body fluids within most of the population. Relating fluid levels of individual compounds to parameters reflecting ovarian reserve in selected populations appears to be an effective way forward and, indeed, some early-stage findings do show some cause for concern. There is a pressing need for the development of practical advice enabling women to minimize their intake of AHR/ER ligands, perhaps through dietary/cosmetic choices or improved food packaging.

Comparison of early versus late initiation of GnRH antagonist co-treatment for controlled ovarian stimulation in IVF: a randomized controlled trial.

STUDY QUESTION: What is the impact of initiating GnRH antagonist co-treatment for in vitro fertilization (IVF) on cycle day (CD) 2 compared with CD 6 on live birth rate (LBR) per started cycle and on the cumulative live birth rate (CLBR)? SUMMARY ANSWER: Early initiation of GnRH antagonist does not appear to improve clinical outcomes of IVF compared with midfollicular initiation. WHAT IS KNOWN ALREADY: During ovarian stimulation for IVF, GnRH antagonist co-treatment is usually administered from the midfollicular phase onwards. Earlier initiation may improve the follicular phase hormonal milieu and therefore overall clinical outcomes. STUDY DESIGN, SIZE, DURATION: This open-label, multicentre randomized controlled trial was conducted between September 2009 and July 2011. A web-based program was used for randomization and 617 IVF-intracytoplasmic sperm injection (ICSI) patients were included. PARTICIPANTS/MATERIALS, SETTING, METHODS: Recombinant FSH (150-225 IU) was administered daily from CD 2 onwards in both groups. The study group (CD2; n = 308) started GnRH antagonist co-treatment on CD 2, whereas the control group (CD6; n = 309) started on CD 6. MAIN RESULTS AND THE ROLE OF CHANCE: There were no significant differences in clinical outcomes between the two groups. A non-significant trend towards a higher LBR per started cycle and CLBR was observed in the CD6 group compared with the CD2 group (LBR: 24.0 versus 21.5%, P = 0.5; CLBR: 29.9 versus 26.7%, P = 0.6). LIMITATIONS, REASONS FOR CAUTION: The study was terminated prematurely because no significant difference was observed in clinical outcomes after 617 inclusions. A much larger study population would be needed to detect a small significant difference in favour of either study arm, which raises the question of whether this would be relevant for clinical practice. WIDER IMPLICATIONS OF THE FINDINGS: The present study shows that the additional treatment burden and costs of starting GnRH antagonist on CD 2 instead of on CD 6 are not justified, as early initiation of GnRH antagonist does not improve LBRs. STUDY FUNDING/COMPETING INTEREST(S): This study was partially supported by a grant from Merck Serono. O.H., M.J.C.E, A.V., P.A.D., R.E.B., G.J.E.O., C.A.G.H., G.C.D.M., H.J.V., P.F.M.H. and A.B. have nothing to declare. F.J.B. has received fees and grant support from the following companies (in alphabetic order): Ferring, Gedeon Richter, Merck Serono, MSD and Roche. B.J.C. has received fees and grant support from the following companies (in alphabetic order): Ferring, Merck Serono and MSD. C.B.L has received fees and grant support from the following companies (in alphabetic order): Auxogen, Ferring, Merck Serono and MSD. B.C.J.M.F. has received fees and grant support from the following companies (in alphabetic order): Andromed, Ardana, Ferring, Genovum, Merck Serono, MSD, Organon, Pantharei Bioscience, PregLem, Schering, Schering Plough, Serono and Wyeth. J.S.E.L. has received fees and grant support from the following companies (in alphabetic order): Ferring, Gennovum, MSD, Merck Serono, Organon, Schering Plough and Serono. N.S.M. has received fees and grant support from the following companies (in alphabetic order): Anecova, Ferring, Merck Serono, MSD, Organon and Serono. TRIAL REGISTRATION NUMBER: www.clinicaltrials.gov, no. NCT00866034.

Expression of neuronal markers in the endometrium of women with and those without endometriosis.

STUDY QUESTION: How do the expression patterns of neuronal markers differ in the endometrium of women with and without endometriosis? SUMMARY ANSWER: The neuronal markers, PGP9.5, NGFp75 and VR1, are expressed in the endometrium at levels that do not differ between women with and without endometriosis. WHAT IS KNOWN ALREADY: Aberrant neuronal growth within the uterus may contribute to abnormal fertility and uterine dysfunction. However, controversy still exists as to whether aberrant innervation in the endometrium is associated with gynaecological pathology such as endometriosis. This may reflect the use of subjective methods such as histology to assess the innervation of the endometrium. We, therefore, employed a quantitative method, western blotting, to study markers of endometrial innervation in the presence and absence of endometriosis. STUDY DESIGN, SIZE, DURATION: This study included 45 women undergoing laparoscopic examination for the diagnosis of endometriosis. Endometrial samples were analysed by western blot for the expression of neuronal and neurotrophic markers, PGP9.5, VR1 and NGFp75. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: Endometrial pipelle biopsies were obtained from patients with (n = 20, study group) and without (n = 25, control group) endometriosis. Tissue was analysed by immunohistochemistry and western blot analysis for the expression of pan-neuronal marker, PGP9.5, sensory nociceptive marker, TPVR1, and low-affinity neurotrophic growth factor receptor, NGFRp75. MAIN RESULTS AND THE ROLE OF CHANCE: PGP9.5, NGFp75 and VR1 were expressed in the endometrium of women, independent of the presence of endometriosis. Furthermore, the expression level of PGP9.5, VR1 and NGFp75 did not alter between the two cohorts of women. LIMITATIONS, REASONS FOR CAUTION: Studies of this nature are subject to the heterogeneous nature of patient population and tissue samples despite attempts to standardize these parameters. Hence, further studies using similar methodology will be required to confirm our results. WIDER IMPLICATIONS OF THE FINDINGS: Our results highlight that sensory neuronal markers are present in women with and without endometriosis. Future work will assess what the targets of the endometrial nerves are and investigate their function, their impact on endometrial biology and, in particular, whether aberrant neuronal function, rather than the mere presence of neuronal function, could be the root cause of subfertility and/or pain affecting many endometriosis sufferers. Our results do not, however, confirm the previous paradigm of increased innervation in the endometrium of women with endometriosis, nor the use of nerve cell detection from pipelle biopsies to diagnose endometriosis.

Supportive care for women with recurrent miscarriage: a survey to quantify women's preferences.

BACKGROUND: Supportive care is regularly offered to women with recurrent miscarriages (RMs). Their preferences for supportive care in their next pregnancy have been identified by qualitative research. The aim of this study was to quantify these supportive care preferences and identify women's characteristics that are associated with a higher or lower need for supportive care in women with RM. METHODS: A questionnaire study was conducted in women with RMs (≥ 2 miscarriages) in three hospitals in the Netherlands. All women who received diagnostic work-up for RMs from January 2010 to December 2010 were sent a questionnaire. The questionnaire quantified supportive care options identified by a previous qualitative study. We next analysed associations between women's characteristics (age, ethnicity, education level, parity, pregnancy during questionnaire and time passed since last miscarriage) and their feelings about supportive care options to elucidate any differences between groups. RESULTS: Two hundred and sixty-six women were asked to participate in the study. In total, 174 women responded (response rate 65%) and 171 questionnaires were analysed. Women with RM preferred the following supportive care options for their next pregnancy: a plan with one doctor who shows understanding, takes them seriously, has knowledge of their obstetric history, listens to them, gives information about RM, shows empathy, informs on progress and enquires about emotional needs. Also, an ultrasound examination during symptoms, directly after a positive pregnancy test and every 2 weeks. Finally, if a miscarriage occurred, most women would prefer to talk to a medical or psychological professional afterwards. The majority of women expressed a low preference for admission to a hospital ward at the same gestational age as previous miscarriages and for bereavement therapy. The median preference, on a scale from 1 to 10, for supportive care was 8.0. Ethnicity, parity and pregnancy at the time of the survey were associated with different preferences, but female age, education level and time passed since the last miscarriage were not. CONCLUSIONS: Women with RM preferred a plan for the first trimester that involved one doctor, ultrasounds and the exercise of soft skills, like showing understanding, listening skills, awareness of obstetrical history and respect towards the patient and their miscarriage, by the health care professionals. In the event of a miscarriage, women prefer aftercare. Women from ethnic minorities and women who were not pregnant during the questionnaire investigation were the two patient groups who preferred the most supportive care options. Tailor-made supportive care can now be offered to women with RM.

Molecular aspects of implantation failure.

Despite expanding global experience with advanced reproductive technologies, the majority of IVF attempts do not result in a successful pregnancy, foremost as a result of implantation failure. The process of embryo implantation, a remarkably dynamic and precisely controlled molecular and cellular event, appears inefficient in humans and is poorly understood. However, insights gained from clinical implantation failure, early pregnancy loss, and emerging techologies that enable molecular interrogation of endometrial-embryo interactions are unravelling this major limiting step in human reproduction. We review current molecular concepts thought to underlie implantation failure, consider the contribution of embryonic and endometrial factors, and discuss the clinical value of putative markers of impaired endometrial receptivity. Finally we highlight the nature of the dialogue between the maternal endometrium and the implanting embryo and discuss the concept of natural embryo selection. This article is part of a Special Issue entitled: Molecular Genetics of Human Reproductive Failure.

Comparison of the phenotype of Chinese versus Dutch Caucasian women presenting with polycystic ovary syndrome and oligo/amenorrhoea.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex disorder with variable prevalence and clinical presentation in different populations, which may be mediated by geographical and ethnic background. METHODS: We performed a comparison of phenotypic characteristics between 547 Chinese and 427 Dutch women with PCOS and oligo/amenorrhoea attending University Reproductive Centers in China and the Netherlands. RESULTS: Chinese women presenting with a clinical diagnosis of PCOS were observed to have a higher incidence of hyperandrogenism (HA) (P < 0.001) and amenorrhoea (P < 0.001) compared with Dutch women, but no difference was observed in the incidence of polycystic ovaries (PCOs). Using population-specific cut-off values, Chinese women with PCOS demonstrated a higher incidence of increased BMI (P < 0.001), waist circumference (WC) (P < 0.001) and waist-hip ratio (P < 0.001) than Dutch women. In both groups, HA was associated with increased age, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and serum LH while PCOs correlated with BMI, WC, HOMA-IR, fasting insulin and elevated total testosterone. Associations specific for ethnic background were found between LH and HA, and between both BMI and HOMA-IR, and PCOs. CONCLUSIONS: Reproductive and metabolic characteristics differed between the two ethnic groups. Chinese women were found to present more frequently with a phenotype associated with increased risk of metabolic complications later in life, compared with Dutch Caucasian women. Ethnicity seems to determine part of the specific phenotypical presentation of PCOS.

Spontaneous LH surges prior to HCG administration in unstimulated-cycle frozen-thawed embryo transfer do not influence pregnancy rates.

LH surges are the start of a period of optimal endometrial receptivity. Missing these surges in an unstimulated-cycle frozen-thawed embryo transfer (FET) based on ultrasound alone might lead to incorrect timing of embryo transfer. This prospective, non-randomized trial established the incidence and effect of spontaneous LH surges on ongoing pregnancy rates and assessed the use of ultrasound without LH monitoring in planning FET. All patients undergoing unstimulated-cycle FET in the study centre over a 2-year period were included in this analysis (n=233). All patients had regular menstrual cycles. Serum LH analysis took place before human chorionic gonadotrophin administration. The main outcome measure was ongoing pregnancy. LH surges occurred in over half of patients. Overall pregnancy rate was 34.3%. Relative risks for ongoing pregnancy for cycles with or without a spontaneous LH surge were not significantly different (ongoing pregnancy rate 33.4% versus 34.8%; RR 1.02, 95% CI 0.7-1.5). Based on these results, it was concluded that LH surges ≥10 IU/l occurred in over 50% of patients, but LH surges demonstrated no significant effect on pregnancy rates. Single LH determination prior to ovulation induction in unstimulated-cycle FET does not seem to have added clinical value.

Risk of borderline and invasive ovarian tumours after ovarian stimulation for in vitro fertilization in a large Dutch cohort.

BACKGROUND: Long-term effects of ovarian stimulation for IVF on the risk of ovarian malignancies are unknown. METHODS: We identified a nationwide historic cohort of 19,146 women who received IVF treatment in the Netherlands between 1983 and 1995, and a comparison group of 6006 subfertile women not treated with IVF. In 1997-1999, data on reproductive risk factors were obtained from 65% of women and data on subfertility (treatment) were obtained from the medical records. The incidence of ovarian malignancies (including borderline ovarian tumours) through 2007 was assessed through linkage with disease registries. The risk of ovarian malignancies in the IVF group was compared with risks in the general population and the subfertile comparison group. RESULTS: After a median follow-up of 14.7 years, the risk of borderline ovarian tumours was increased in the IVF group compared with the general population [standardized incidence ratio (SIR) = 1.76; 95% confidence interval (CI) = 1.16-2.56]. The overall SIR for invasive ovarian cancer was not significantly elevated, but increased with longer follow-up after first IVF (P = 0.02); the SIR was 3.54 (95% CI = 1.62-6.72) after 15 years. The risks of borderline ovarian tumours and of all ovarian malignancies combined in the IVF group were significantly increased compared with risks in the subfertile comparison group (hazard ratios = 4.23; 95% CI = 1.25-14.33 and 2.14; 95% CI = 1.07-4.25, respectively, adjusted for age, parity and subfertility cause). CONCLUSIONS: Ovarian stimulation for IVF may increase the risk of ovarian malignancies, especially borderline ovarian tumours. More large cohort studies are needed to confirm these findings and to examine the effect of IVF treatment characteristics.

Clinical outcomes in relation to the daily dose of recombinant follicle-stimulating hormone for ovarian stimulation in in vitro fertilization in presumed normal responders younger than 39 years: a meta-analysis.

BACKGROUND: The optimal ovarian stimulation dose to obtain the best balance between the probability of pregnancy and the risk of complications, while maximizing cost-effectiveness of in vitro fertilization (IVF) treatment, is yet to be established. METHODS: A systematic search of the electronic databases PubMed, EMBASE and Cochrane library, from 1984 until October 2009 for randomized controlled trials comparing different doses of recombinant FSH in IVF, was performed. RESULTS: Ten studies (totaling 1952 IVF cycles) were included in the present meta-analysis, comprising patients younger than 39 years with regular menstrual cycle, normal basal FSH levels and two normal ovaries. Comparison was made between studies using a daily dose of 100 versus 200 IU recFSH, and between 150 versus 200 IU recFSH or higher. Although oocyte yield was greater in the >200 IU/day dose group, pregnancy rates were similar compared with lower dose groups. The risk of insufficient response to ovarian stimulation was greatest in the 100 IU/day dose group. The risk of developing ovarian hyperstimulation syndrome was greater in the >200 IU/day dose group. The number of embryos available for cryopreservation was lowest in the 100 IU/day group, but similar comparing the 150 IU/day and the >200 IU/day dose groups. CONCLUSIONS: This meta-analysis suggests that the optimal daily recFSH stimulation dose is 150 IU/day in presumed normal responders younger than 39 years undergoing IVF. Compared with higher doses, this dose is associated with a slightly lower oocyte yield, but similar pregnancy and embryo cryopreservation rates. Furthermore, the wide spread adherence to this optimal dose will allow for a considerable reduction in IVF costs and complications.