Emre Seli

Abnormal spermatozoa in the ejaculate: abortive apoptosis and faulty nuclear remodelling during spermatogenesis.

The mechanisms responsible for producing abnormal spermatozoa in the ejaculate are relatively unknown. Numerous studies have now shown the presence of nuclear DNA strand breaks in human ejaculated spermatozoa and the abnormal persistence of apoptotic marker proteins. The reason why human spermatozoa, in particular from men with abnormal semen parameters, possess these abnormalities is still not clear. Two processes that have been linked to the presence of nuclear DNA strand breaks in spermatozoa are anomalies in apoptosis during spermatogenesis or problems in the replacement of histones with protamines during spermiogenesis. Understanding the mechanisms responsible for producing abnormal spermatozoa in the human will improve knowledge about certain causes of male infertility.

Noninvasive metabolomic profiling of human embryo culture media using Raman spectroscopy predicts embryonic reproductive potential: a prospective blinded pilot study.

OBJECTIVE To determine if metabolomic profiling of embryonic development was associated with implantation rates in IVF. DESIGN Prospective blinded. SETTING University-affiliated assisted reproductive technology program. PATIENT(S) Unselected assisted reproductive technology population. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Raman-based biospectroscopic metabolomic profiling of spent culture media and delivery rates. RESULTS Forty-one spent media samples from 19 patients with known reproductive potential (0 or 100% delivery rates of each embryo that implanted) were evaluated. Raman-based metabolomic profiling was used to calculate a viability index for each sample. On day 3, the spent media of embryos with proven reproductive potential (n = 33) demonstrated higher viability indices (0.875 +/- 0.12) than those that failed to implant (0.56 +/- 0.09). Similar findings were present in spent media from embryos transferred on day 5 (n = 8) (-0.40 +/- -0.21 vs. -0.81 +/- -0.08). Receiver operating characteristic curve analyses were used to select thresholds with the greatest ability to discriminate outcomes. Overall diagnostic accuracy for predicting delivery or a failed implantation was 80.5%. CONCLUSIONS There is a clear relationship between the reproductive potential of human embryos and their modification of their culture media as detected by Raman biospectroscopy-based metabolomic profiling. This technology offers great potential for development as a tool to allow rapid noninvasive assessment of embryonic reproductive potential before transfer.

Metabolomics and its application for non-invasive embryo assessment in IVF

Morphology and cleavage rate remain the mainstay of embryo assessment. However, a number of additional technologies for this application are under investigation. These include the measurement of glucose, lactate, pyruvate or amino acid levels in the embryo culture media, assessment of oxygen consumption by the embryo, genomic and proteomic profiling, and most recently, analytical examination of the embryonic metabolome. As the number of assisted reproduction cycles increases worldwide, improvements in the ability to quickly and non-invasively identify the best embryos for transfer remain a critical goal for reproductive medicine. Recent studies suggest that metabolomic profiling of embryo culture media using optical and non-optical spectroscopies may provide a useful adjunct to the current embryo assessment strategies and provide insight into the phenotype of embryos with increasing reproductive potential.

Noninvasive metabolomic profiling of embryo culture media using proton nuclear magnetic resonance correlates with reproductive potential of embryos in women undergoing in vitro fertilization

OBJECTIVE To identify biomarkers associated with reproductive outcome using proton nuclear magnetic resonance ((1)H NMR) metabolomic profiling of embryo culture media. DESIGN Retrospective study. SETTING An academic assisted reproductive technology (ART) program; a university research center. PATIENT(S) Women undergoing ART treatment. INTERVENTION(S) Spent media samples from embryos that resulted in pregnancy and delivery (n = 17) and samples (n = 17) from embryos that failed to implant were individually collected on day 3, and evaluated using (1)H NMR spectroscopy. The spectra obtained were quantified by integrating six biomarker signals in the aliphatic region after baseline subtraction. Using a multivariate analysis, a model that calculates a viability index for each spectrum was developed. Sensitivity and specificity of predicting pregnancy (described as implantation and delivery) were calculated. MAIN OUTCOME MEASURE(S) The (1)H NMR metabolomic profile of embryo culture media and embryo viability. RESULT(S) Glutamate concentrations determined by (1)H NMR were significantly higher in spent culture media of embryos that resulted in pregnancy and delivery compared to those that failed to implant. Similarly, viability indices calculated by (1)H NMR using the weighted coefficients of glutamate and alanine/lactate ratio quantities were higher for embryos that implanted and resulted in a delivery. Proton NMR spectroscopy predicted viability of individual embryos with a sensitivity of 88.2% and a specificity of 88.2%. CONCLUSION(S) Metabolomic profile of spent embryo culture media using (1)H NMR correlates with the reproductive potential of embryos.

Noninvasive metabolomic profiling as an adjunct to morphology for noninvasive embryo assessment in women undergoing single embryo transfer

OBJECTIVE To determine whether metabolomic profiling of spent embryo culture media correlates with reproductive potential of human embryos. DESIGN Retrospective study. SETTING Academic and a private assisted reproductive technology (ART) programs. PATIENT(S) Women undergoing single embryo transfer after IVF. INTERVENTION(S) Spent embryo culture media were collected after single embryo transfer on day 3 (n = 304) or day 2 (n = 181) and analyzed by near infrared spectroscopy. Near infrared spectral regions were correlated to reproductive potential using a genetic algorithm optimization. Models of these spectral regions were used to calculate viability indices, and were validated by blinded analysis of a subset (n = 60) of samples. Implantation rates were also compared between embryos of higher (>or=0.3) and lower (<0.3) viability indices, and within each morphology grade. MAIN OUTCOME MEASURE(S) Viability index and embryo viability. RESULT(S) Mean viability indices of embryos that resulted in positive fetal cardiac activity were significantly higher compared with embryos that did not for both day 2 and day 3 embryos. Blinded validation of the day 2 model proved to be significant. Increasing viability index values correlated with an increase in pregnancy. Viability indices were found to be independent of morphology for both day 2 and day 3 embryos. Implantation rates were significantly higher among embryos with viability indices >or=0.3. CONCLUSION(S) Metabolomic profiling of human embryo culture media using near infrared spectroscopy is independent of morphology and correlates with reproductive potential of embryos.

Fertility preservation options for female patients with malignancies.

Purpose of review Preservation of fertility in female patients diagnosed with cancer has recently been an area of intensive investigation. This review summarizes available options and discusses recently published data concerning experimental methods. Specific strategies for fertility preservation in women with gynecologic malignancies are also presented. Recent findings Success with ovarian stimulation protocols using tamoxifen or aromatase inhibitors has recently been reported for women with breast cancer who attempt embryo cryopreservation prior to chemotherapy. The first embryo transfer using oocytes retrieved from cryopreserved ovarian tissue implanted at a heterotopic location, the first pregnancy following orthotopic transplantation of cryopreserved ovarian tissue, and increasing success with oocyte cryopreservation were also reported. Summary Fertility preservation in female patients with cancer has become an important health issue due to increasing survival rates and delayed childbearing especially in Western countries. Radical vaginal trachelectomy for cervical cancer, conservative surgery for ovarian tumors, and progestin treatment in endometrial cancers may be considered at early stages in order to preserve fertility. Embryo cryopreservation is an established technique that is available for fertility preservation, providing a delay in the initiation of chemotherapy or radiotherapy is acceptable, and a partner or donor sperm is available. Additional techniques that could be offered after counseling the patient about their experimental nature include oocyte cryopreservation, ovarian cryopreservation, and gonadotropin-releasing hormone agonist co-treatment with chemotherapy. Improvement of these techniques as well as better characterization of their success rates and risks await further investigation.

OMICS in assisted reproduction: possibilities and pitfalls

A key step in assisted reproduction is the assessment of oocyte and embryo developmental potential in order to determine the embryo(s) most likely to result in pregnancy. Currently used embryo assessment strategies are largely based on embryo morphology and cleavage rate. Although these systems have been successful in improving pregnancy rates and reducing multiple gestations, their precision is still insufficient. Therefore, development of an objective, accurate, fast and affordable test that can aid in the assessment of oocyte and embryo developmental potential is a significant aim of reproductive medicine. Recently, global assessment strategies involving genomic, transcriptomic, proteomic or metabolomic profiling of oocytes, granulosa or cumulus cells, embryos or culture media have been applied to assisted reproduction. These technologies are at different stages of development and present unique advantages as well as limitations.

Assessment of embryo viability in assisted reproductive technology: shortcomings of current approaches and the emerging role of metabolomics.

Purpose of review The present article describes the current status of embryo assessment in assisted reproductive technologies and discusses two important issues that derive, at least in part, from our inability to adequately assess the reproductive potential of individual embryos: low implantation rates and high multiple pregnancy rates. After an overview of studies evaluating embryo metabolism as a predictor of embryo viability, use of metabolomics and additional emerging approaches for rapid, noninvasive, embryo assessment are discussed. Recent findings Morphology and cleavage rate remain the mainstay of embryo assessment. A number of technologies are, however, under investigation. These include the assessment of glucose, lactate, pyruvate, and amino acid metabolism, proteomic profiling, evaluation of oxygen consumption, and most recently, examination of the metabolome. Summary As the number of assisted reproductive technology cycles increases worldwide, improvements in the ability to quickly and noninvasively determine the best embryos for transfer remain a critical goal for reproductive medicine. Recent studies suggest that metabolomic profiling of embryo culture media may provide a useful adjunct to the current embryo assessment strategies based on morphology and cleavage rate.

The significance of sperm nuclear DNA strand breaks on reproductive outcome.

Purpose of review A growing body of evidence indicates that ejaculated spermatozoa from men being treated with intracytoplasmic sperm injection contain nuclear abnormalities. Many of these nuclear anomalies manifest themselves as breaks in the sperm nuclear DNA. This review examines the mechanisms involved in generating DNA strand breaks during spermatogenesis in the human, the main techniques used to assess the sperm nucleus and the evidence, in relation to assisted reproduction, showing that sperm nuclear DNA strand breaks may impact on reproductive outcome. Recent findings Techniques such as the TUNEL assay and the sperm chromatin structure assay both show increased levels of DNA abnormalities in spermatozoa from men who have poor semen parameters. The reproductive parameters affected by an increased presence of DNA abnormalities in ejaculated spermatozoa include fertilization, blastocyst development, and pregnancy rates. Summary There is accumulating evidence linking sperm nuclear DNA anomalies to poor reproductive outcome in relation to assisted reproduction technologies. The tests currently available only provide an inkling of the impact of sperm nuclear DNA abnormalities on reproductive outcomes. Although the impact an abnormal paternal genome may have on reproductive outcome is unquestionably less than that of its female counterpart, it cannot be ignored.

Evidence-based diagnosis and management of tubal factor infertility.

Purpose of review The investigation for potential tubal disease is an essential step in the work-up of infertility. This review article provides an evidence-based overview of the diagnosis and management of tubal factor infertility. Recent findings While laparoscopic chromopertubation remains the gold standard in the diagnosis of tubal disease and hysterosalpingography is still widely used, newer modalities offer some advantages. Sonohysterography with the use of contrast medium is superior to hysterosalpingography and comparable to laparoscopic chromotubation in diagnosing tubal blockage. Chlamydia serology is the most cost-effective and least invasive diagnostic test for tubal disease, and it is comparable to, if not better than, hysterosalpingography. Depending on the nature and degree of tubal dysfunction as well as the age and ovarian reserve of the patient, various treatments for tubal infertility are available. For proximal tubal obstruction, transcervical tubal cannulation with tubal flushing is a reasonable first approach. Surgical techniques for tubal repair, such as salpingostomy or fimbrioplasty for distal tubal obstruction, can provide good results. Still, tubal factor remains a major indication for in-vitro fertilization and embryo transfer, which bypasses the tubal problem altogether. In certain situations, such as the presence of hydrosalpinx, prophylactic surgery can be used in conjunction with in-vitro fertilization and embryo transfer. Summary As with infertility in general, the diagnosis and management of tubal infertility should be tailored to the individual patient. Future studies should help to further clarify the role of the various diagnostic tests and therapeutic approaches for tubal infertility.