SciCombinator

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Concept: Implantation

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Experimental ooplasmic transplantation from donor to recipient oocyte took place between 1996 and 2001 at Saint Barnabas Medical Center, USA. Indication for 33 patients was repeated implantation failure. Thirteen couples had 17 babies. One patient delivered twins from mixed ooplasmic and donor egg embryos. A limited survey-based follow-up study on the children is reported: 12 out of 13 parents completed a questionnaire on pregnancy, birth, health, academic performance and disclosure. Parents of a quadruplet did not participate. Prenatal development and delivery were uneventful. School grades ranged from good to excellent. Children were of good health. Body mass index (BMI) was normal in 12 out of 13 children. One child had chronic migraine headaches, two mild asthma, three minor vision and three minor skin problems. One boy from a boy/girl twin was diagnosed with borderline pervasive developmental disorder - not otherwise specified at age 18 months, but with no later symptoms. One couple disclosed the use of egg donor to their child. One reported intention to disclose; six were undecided and four reported they would not disclose. This limited follow-up strategy presents a high risk of bias. Parents may not assent to standardized clinical analysis owing to lack of disclosure to their children.

Concepts: Pregnancy, Childbirth, Asthma, Embryo, Body mass index, Pervasive developmental disorder, Implantation, Zygote

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OBJECTIVE: To determine the diagnostic value of the following sperm function tests in predicting the fertilizing ability of spermatozoa in conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI): hyaluronan-binding assay (HBA), DNA fragmentation (Halosperm), and hyperactivity. DESIGN: Prospective study. SETTING: University medical center. PATIENT(S): 133 couples undergoing infertility treatment with IVF/ICSI. INTERVENTION(S): Analysis of sperm DNA fragmentation, hyaluronan-binding ability, and hyperactivation on washed semen samples used for the insemination of oocytes. MAIN OUTCOME MEASURE(S): Correlation between the results of sperm function tests and the fertilization rate (FR) or embryo quality (EQ) after IVF and ICSI. Comparison of the sperm DNA fragmentation, hyperactivation, and hyaluronan binding ability between cycles with less than 50% (group 1) and more than 50% (group 2) of oocytes fertilized after IVF. RESULT(S): Both FR and EQ in IVF cycles negatively correlated with sperm DNA fragmentation. Furthermore, a positive correlation was observed between FR and hyaluronan-binding ability or induced hyperactivity. The semen samples from the IVF cycles with low FR (group 1) were characterized by statistically significantly higher sperm DNA fragmentation and lower hyaluronan-binding ability in comparison with semen samples from the group with high levels of fertilization (group 2). In ICSI cycles, no relationship was found between sperm function tests and FR or EQ. CONCLUSION(S): The Halosperm test, the HBA test, and induced hyperactivity are useful in predicting the ability of spermatozoa to fertilize oocytes in IVF and are helpful in distinguishing semen samples suitable for IVF or ICSI.

Concepts: Reproduction, Sperm, Fertility, Spermatozoon, In vitro fertilisation, Semen, Implantation, Fertilisation

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The primary limiting factor for effective IVF treatment is successful embryo implantation. Recurrent implantation failure (RIF) is a condition whereby couples fail to achieve pregnancy despite consecutive embryo transfers. Here we describe the collection of gene expression profiles from mid-luteal phase endometrial biopsies (n = 115) from women experiencing RIF and healthy controls. Using a signature discovery set (n = 81) we identify a signature containing 303 genes predictive of RIF. Independent validation in 34 samples shows that the gene signature predicts RIF with 100% positive predictive value (PPV). The strength of the RIF associated expression signature also stratifies RIF patients into distinct groups with different subsequent implantation success rates. Exploration of the expression changes suggests that RIF is primarily associated with reduced cellular proliferation. The gene signature will be of value in counselling and guiding further treatment of women who fail to conceive upon IVF and suggests new avenues for developing intervention.

Concepts: Gene, Pregnancy, Genetics, Gene expression, Cell, Embryo, Implantation, Success

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Implantation of the blastocyst is a developmental milestone in mammalian embryonic development. At this time, a coordinated program of lineage diversification, cell-fate specification, and morphogenetic movements establishes the generation of extra-embryonic tissues and the embryo proper, and determines the conditions for successful pregnancy and gastrulation. Despite its basic and clinical importance, this process remains mysterious in humans. Here we report the use of a novel in vitro system to study the post-implantation development of the human embryo. We unveil the self-organizing abilities and autonomy of in vitro attached human embryos. We find human-specific molecular signatures of early cell lineage, timing, and architecture. Embryos display key landmarks of normal development, including epiblast expansion, lineage segregation, bi-laminar disc formation, amniotic and yolk sac cavitation, and trophoblast diversification. Our findings highlight the species-specificity of these developmental events and provide a new understanding of early human embryonic development beyond the blastocyst stage. In addition, our study establishes a new model system relevant to early human pregnancy loss. Finally, our work will also assist in the rational design of differentiation protocols of human embryonic stem cells to specific cell types for disease modelling and cell replacement therapy.

Concepts: Pregnancy, Embryo, Developmental biology, Cellular differentiation, Embryonic stem cell, Embryology, Implantation, Inner cell mass

46

CDC has updated its interim guidance for persons with possible Zika virus exposure who are planning to conceive (1) and interim guidance to prevent transmission of Zika virus through sexual contact (2), now combined into a single document. Guidance for care for pregnant women with possible Zika virus exposure was previously published (3). Possible Zika virus exposure is defined as travel to or residence in an area of active Zika virus transmission (http://www.cdc.gov/zika/geo/index.html), or sex* without a condom(†) with a partner who traveled to or lived in an area of active transmission. Based on new though limited data, CDC now recommends that all men with possible Zika virus exposure who are considering attempting conception with their partner, regardless of symptom status,(§) wait to conceive until at least 6 months after symptom onset (if symptomatic) or last possible Zika virus exposure (if asymptomatic). Recommendations for women planning to conceive remain unchanged: women with possible Zika virus exposure are recommended to wait to conceive until at least 8 weeks after symptom onset (if symptomatic) or last possible Zika virus exposure (if asymptomatic). Couples with possible Zika virus exposure, who are not pregnant and do not plan to become pregnant, who want to minimize their risk for sexual transmission of Zika virus should use a condom or abstain from sex for the same periods for men and women described above. Women of reproductive age who have had or anticipate future Zika virus exposure who do not want to become pregnant should use the most effective contraceptive method that can be used correctly and consistently. These recommendations will be further updated when additional data become available.

Concepts: Pregnancy, Birth control, Sexual intercourse, Reproduction, Fertility, In vitro fertilisation, Human sexual behavior, Implantation

31

The creation of a living heart valve is a much-wanted alternative for current valve prostheses that suffer from limited durability and thromboembolic complications. Current strategies to create such valves, however, require the use of cells for in vitro culture, or decellularized human- or animal-derived donor tissue for in situ engineering. Here, we propose and demonstrate proof-of-concept of in situ heart valve tissue engineering using a synthetic approach, in which a cell-free, slow degrading elastomeric valvular implant is populated by endogenous cells to form new valvular tissue inside the heart. We designed a fibrous valvular scaffold, fabricated from a novel supramolecular elastomer, that enables endogenous cells to enter and produce matrix. Orthotopic implantations as pulmonary valve in sheep demonstrated sustained functionality up to 12 months, while the implant was gradually replaced by a layered collagen and elastic matrix in pace with cell-driven polymer resorption. Our results offer new perspectives for endogenous heart valve replacement starting from a readily-available synthetic graft that is compatible with surgical and transcatheter implantation procedures.

Concepts: Surgery, Polymer, Implantation, Valvular heart disease, Valve, Valves, Check valve, Ball valve

31

The objective was to determine the likelihood of conceiving spontaneously following cessation of IVF/ICSI; how long does it take and what factors are associated with conception? The design was an internet-based survey. All registered users of www.ivf-infertility.com received an electronic questionnaire addressing issues relating to the duration and cause of infertility, number of IVF/ICSI cycles and outcome, whether they conceived following cessation of IVF/ICSI and the time taken to conceive and outcome. Four hundred and eighty four patients responded of whom 403 met the study criteria. The overall cumulative live birth rate over a 6-year period following cessation of IVF/ICSI was 29%. Eighty-two percent of conceptions occurred within 2 years. Positive factors associated with spontaneous conception were unexplained infertility (p = 0.02), ovulation dysfunction (p = 0.01), infertility less than four years prior to IVF/ICSI (p = 0.045) and 2 years or less since discontinuation of IVF/ICSI (p < 0.001) and up to four attempts at IVF/ICSI (p = 0.02). In conclusion, 29% of couples conceived spontaneously over a 6-year period following the cessation of IVF/ICSI. The findings of this study can be used to counsel and reassure women following IVF/ICSI.

Concepts: Pregnancy, Fertility, In vitro fertilisation, Menstrual cycle, Abortion, Implantation

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To discern the potential effect of ovarian stimulation on implantation potential by comparing ongoing pregnancy rates from matched blastocysts in fresh and frozen-thawed single-embryo-transfer cycles.

Concepts: In vitro fertilisation, Endometrium, Implantation

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To evaluate embryos with direct cleavage (≤5 hours) from two to three cells (DC2-3) and correlate this morphokinetic parameter to implantation and ongoing pregnancy.

Concepts: Pregnancy, Reproduction, Embryo, Fetus, Developmental biology, Endometrium, Implantation, Zygote

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OBJECTIVE: Although extensive evidence indicates the hyperinsulinemia directly contributes to reproductive dysfunction in polycystic ovarian syndrome (PCOS), influence of insulin resistance (IR) on assisted reproductive technology outcomes is poorly understood. In this study we aimed to evaluate the effects of IR on in vitro maturation - in vitro fertilization-embryo transfer (IVM-IVF-ET) in patients with PCOS. DESIGN: Prospective observational study. PATIENTS: Women with PCOS (n = 115) commencing IVM. MEASURMENTS: IR (n = 51) and non-IR (n = 64) women with PCOS ready to commence an IVM cycle were recruited. IR was diagnosed using the glucose tolerance test (GTT) and homeostasis model assessment (HOMA) index. Patients with an abnormal GTT and/or HOMA index > 2.4 were considered IR. Patients underwent 115 cycles of unstimulated hCG-primed IVM. RESULTS: Maturation, fertilization, cleavage rates, the number of good-quality embryo, and blastocyst formation rates were not significantly different between groups. However, implantation (11.6% vs 28.7%, P = 0.001, respectively), clinical pregnancy (23.5% vs 53.1%, P = 0.002, respectively), and ongoing pregnancy rates (21.6% vs 46.9%. P = 0.006, respectively) were significantly decreased in the IR group. The negative effect of IR on pregnancy outcomes remained after controlling for age, body mass index (BMI) and lipid profiles (OR 4.928, 95% CI 1.735-13.991, P = 0.003). CONCLUSIONS: Pregnancy rate after IVM is impaired in IR patients with PCOS. Oocyte development and embryo quality are not affected, suggesting that the effects of hyperinsulinemia on endometrial function and implantation process underlie the decreased pregnancy rate. © 2012 Blackwell Publishing Ltd.

Concepts: Pregnancy, Embryo, Glucose tolerance test, In vitro fertilisation, Menstrual cycle, Implantation, Polycystic ovary syndrome, Blastocyst