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Time-Lapse Imaging and Preimplantation Genetic Testing
Published in Darren K. Griffin, Gary L. Harton, Preimplantation Genetic Testing, 2020
Several time-lapse incubation devices are now commercially available for the IVF laboratory. They are designed to capture images of the fertilizing and developing embryos at regular intervals (commonly 5–20 minutes apart) throughout the in-vitro culture period, avoiding the need to remove the embryos from the protected and optimized environment for visual microscopic assessment. The EmbryoscopeTM (Vitrolife, Sweden) was the first instrument to provide this relatively stable, “uninterrupted” incubation combined with internal microscopy as an alternative to a standard IVF incubator. The introduction of such time-lapse devices has resulted in a plethora of reports describing human preimplantation embryo development in greater detail, with descriptions of both its theoretical and demonstrable impact on embryo selection and clinical outcomes [6–8].
Nutraceuticals and Hormonal Balance in Pregnancy
Published in Priyanka Bhatt, Maryam Sadat Miraghajani, Sarvadaman Pathak, Yashwant Pathak, Nutraceuticals for Prenatal, Maternal and Offspring’s Nutritional Health, 2019
Ashley Oake, Michaela McMahon, Yashwant V. Pathak
During embryo development in uterus, the pregnancy hormone human chorionic gonadotropin (HcG) is secreted by syncytiotrophoblast cells, and later in pregnancy it is produced by the placenta as a placental hormone. The body produces HcG during pregnancy for many reasons, including preparing the mother’s body for the growing fetus by aiding in the release of other hormones, which can also result in a positive pregnancy test. After the egg has been fertilized and attaches to the uterine wall, HcG nourishes the egg for continued development (10). It promotes progesterone production by the corpus luteum, uterine growth in line with the growth of the fetus, growth and differentiation of fetal organs, and the growth of the umbilical cord. HcG receptors found in the hippocampus, hypothalamus, and brain stem of an adult brain take part in nausea and vomiting, affecting 50%–90% of pregnant women (7). There is a strong peak in HcG levels during the first trimester, typically doubling every 72 hours, until 8–11 weeks of pregnancy, where the hormone will then level off (10). Studies have also correlated the structure of HcG and the thyroid-stimulating hormone to suggest the reaction between them stimulates the thyroid gland (10).
The role of lifestyle factors in recurrent implantation failure
Published in Efstratios M. Kolibianakis, Christos A. Venetis, Recurrent Implantation Failure, 2019
Vicki Nisenblat, Robert J. Norman
Both oocytes and sperm are susceptible to the environmental influences, which can subsequently affect embryo development.9,10 Nutrition and other factors originating from the environment can adversely influence maternal health, the intrauterine milieu, and, possibly, maternal response to the implanting embryo.11 It has been recently proposed that women with RIF have a different metabolic status compared with women who have highly receptive endometria.12 RIF has been associated with higher levels of serum glucose and altered levels of the metabolites related to energy, amino acid, and lipid metabolism, suggesting a possibility of metabolic dysfunction.12 At the endometrial level, impaired glucose uptake has been implicated in abnormal decidualization, poor implantation, and pregnancy loss,13 whereas normal glucose metabolism was associated with successful decidualization.14 Certain lifestyle factors such as smoking, alcohol, and obesity are known to induce chronic oxidative stress, which has been extensively linked with reproductive dysfunction on oocyte, tubal, and endometrial levels.15 Elevated levels of adipic acid, a by-product metabolite of reactive oxygen species (ROS) has been detected in the circulation of women with RIF, indicating that women with RIF have an increased oxidative stress state, and the condition can be possibly linked with environmentally induced oxidative damage.12
Obstetric, neonatal and child development outcomes following assisted hatching treatment: a retrospective cohort study
Published in Gynecological Endocrinology, 2021
Maya Shats, Daphna Fenchel, Guy Katz, Jigal Haas, Ronit Machtinger, Itai Gat, Raoul Orvieto, Alon Kedem
Hatching of the blastocyst is a critical step before embryo implantation into the endometrium, and failure to hatch is thought to be one of the limiting factors of subsequent embryo development [1,2]. Assisted hatching (AH) is a method involving artificial disruption of the zona pellucida. Several AH techniques are available, including zona thinning, zona drilling (breaching by forming a hole) and complete removal of the zona, which use chemicals, mechanical techniques, or lasers [3]. AH has been proposed as a method for improving the ability of the embryo to implant after in vitro fertilization (IVF) [3]. Indications for AH vary from one medical center to another, however two or more failed IVF cycles, poor embryo quality and women of advanced reproductive age are generally considered indications for this treatment [4].
The outcomes after transfers of embryos with chromosomal mosaicism: a single reproductive medicine center experience at iVF Riga clinic
Published in Gynecological Endocrinology, 2020
Baiba Alksere, Ieva Grinfelde, Liene Kornejeva, Aigars Dzalbs, Natalija Vedmedovska, Irina Kovalova, Una Conka, Santa Andersone, Sandra Krasucka, Arita Blumberga, Dace Berzina, Violeta Fodina
Mosaicism of genetic material is described as two or more different cell lineages in one organism. This phenomena in PGT-A genetic analysis by aCGH and NGS sometimes is difficult to recognize or to distinguish from artifacts because of tissue specificity, technical conditions, or phenotypic variations. In our subject group, biochemical and clinical pregnancy/livebirth rates differed only slightly between aCGH and NGS groups. Our results are similar to those obtained by Yang et al. [8], where diversities in pregnancies and livebirths did not exceed 10%. The effect of each mosaic is unique in each case, and it is problematic to make adequate interpretations and statistically significant results in the shortage of well-defined genotypes and phenotypes, and limited subject groups [9]. Embryos, where chromosomal aberration is derived from meiosis mainly develop as 100% aneuploids. In such cases, the prediction of pregnancy outcome can be made convincingly [10]. The source for trisomic mosaics is either of a somatic or meiotic origin. Somatic aneuploidies are more often, but are excluded by placental tissue and with marginal clinical result [11]. The consequences of embryo development involve many variables – chromosome number, proportion of abnormal cells, and the location of aberrant cell lineages [12]. Mosaicism of trisomies is present in 1–2% of chorion villus samples (CVS). In cases of confined chorionic mosaicism (CCM), pregnancy outcomes are mostly normal, and adverse results arise from aberrant cells in the fetus or uniparental disomies [13].
Relationship between granulocyte–macrophage colony-stimulating factor, embryo quality, and pregnancy outcomes in women of different ages in fresh transfer cycles: a retrospective study
Published in Journal of Obstetrics and Gynaecology, 2020
Dapeng Chu, Lei Fu, Wenhui Zhou, Yuan Li
GM-CSF supplementation increased the biochemical pregnancy rate in patients over 38 years old (42.1 vs. 18.8%), but this increase was not statistically significant. However, GM-CSF did produce significant differences regarding cleavage and blastocyst formation in subjects over 38 years old. Therefore, it can reasonably be inferred from these findings that GM-CSF benefits embryos with poorer development potential and alleviates culture stress induced by suboptimal conditions. This hypothesis can explain the present study’s results since the improvement of embryo quality was only observed in patients over 38 years old, whose embryo development potential is relatively lower compared with that of younger subjects. A similar conclusion was also found in mouse experiments (Karagenc et al. 2005).