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Preimplantation genetic diagnosis (PGD) was introduced in the late 1980s and represents an option for couples at risk of transmitting an inherited, debilitating or neurological disorder to their children. From a cleavage or blastocyst stage embryo, cell(s) are collected and then genetically analyzed for disease; enabling an unaffected embryo to be transferred into the uterus cavity. Nowadays, PGD has been carried out for several hundreds of heritable conditions including myotonic dystrophy, and for susceptibility genes involved in cancers of the nervous system. Currently, advanced molecular technologies with better resolution, such as array comparative genomic hybridisation, quantitative polymerase chain reaction, and next generation sequencing, are on the verge of becoming the gold standard in embryo preimplantation screening. Given this, it may be time for neurological societies to consider the published evidence to develop new guidelines for the integration of PGD into modern preventative neurology. Therefore, the main aim of this review is to illustrate the option of PGD to enable conception of an unaffected baby, and to assist clinicians and neurologists in the counseling of the patient at risk of transmitting an inherited disease, to explore the genetic journey throughout in vitro fertilization IVF with PGD.

Infertility has become an increasingly common health problem and has been estimated to affect approximately 10% of women in the reproductive age. Due to its high prevalence, it has been deemed a social disease by the World Health Organization (WHO). The causes of infertility are numerous and vary from person to person. As for treatment, the three main therapeutic strategies include pharmacological therapy, surgical therapy - mostly endoscopy, and assisted reproductive technology (ART). Recent decades have witnessed great progress in ART, resulting in successful treatment of the previously untreatable cases, particularly in the field of fertility preservation, preimplantation screening for aneuploidy, uterine transplantations and mitochondrial replacement techniques as prevention against a number of severe diseases. Regardless, ART treatment does not guarantee pregnancy and live birth. The success rate is much smaller as compared to the failure rate, it being among its most important limitations. Embryo implantation is an extremely complex process and represents the most critical step of the reproduction process in humans. Attempts to evaluate endometrial receptivity and strategies for its correction have been discussed. The search for new effective predictors of an individual prognosis remains a crucial challenge for the contemporary reproductive medicine.

The purpose of this study is to report a successful twin pregnancy and delivery in a female patient with X-linked dominant incontinentia pigmenti (IP) who underwent assisted reproductive technology followed by preimplantation genetic screening (PGS). A 29-year-old female with IP had a previous history of recurrent spontaneous abortion. A molecular analysis revealed the patient had a de novo mutation, 1308_1309insCCCCTTG(p.Ala438ProfsTer26), in the inhibitor of the kappa B kinase gamma gene located in the Xq28 region. IVF/ICSI and PGS was performed, in which male embryos were sexed using array-based comparative genomic hybridization (aCGH). After IVF/ICSI and PGS using aCGH on seven embryos, two euploid male blastocysts were transferred with a 50% probability of a viable male pregnancy. The dizygotic twin pregnancy was confirmed and the amniocentesis results of each twin were normal with regard to the mutation found in the mother. The pa tient delivered healthy twin babies during the 37th week of gestation. This case shows the beneficial role of PGS in achieving a successful preg nancy through euploid male embryo gender selection in a woman with X-linked dominant IP with a history of multiple male miscarriages.

Chromosomal abnormalities arising after fertilization, are observed at a relatively high rate at the cleavage stage. To evaluate the aneuploidy and mosaicism, microarray comparative genomic hybridization (CGH) of trophectoderm cells from blastocysts has been considered in preimplantation screening. However, 1% or less of live births are children with chromosomal abnormalities. In this paper, cytogenetic features of patients with chromosomal abnormalities and methods for detecting the disorders are described. Consideration of the utilities and limitations of cytogenetic techniques is essential in the clinical setting.

Our objective is to describe a successful live birth from oocyte vitrification followed by thaw, fertilization, blastocyst culture, trophectoderm biopsy, vitrification, and subsequent thaw. Fifteen mature oocytes were frozen from a patient with uterine factor infertility. Thirteen oocytes survived the thaw, and five underwent trophectoderm biopsy and were refrozen. Three euploid embryos were obtained. A single euploid embryo was transferred in the second thaw cycle to a known recipient leading to the delivery of a normal male infant. This case report is proof of the concept that preimplantation screening and diagnosis is an option for fertility preservation patients.

PURPOSE OF REVIEW Embryo implantation remains the rate-limiting step in assisted conception programmes. Factors affecting the interactions between blastocyst and endometrium are subjects of current research and, sadly, have also been the subjects of much confusion. This review aims to present current thinking on factors affecting embryo development, endometrial receptivity during and around the implantation window and the evidence for and against various proposed treatment options RECENT FINDINGS Age-related aneuploidies of the sex chromosomes and several other autosomes are now thought to adversely affect oocyte and embryo quality, leading to repeat in-vitro fertilization failures. Several small controlled trials have suggested improvements in clinical outcomes following preimplantation screening and blastocyst transfer for aneuploidy in older women. These are, however, very costly, wasteful of embryos and do not appear beneficial after the age of 40 years. Factors influencing endometrial receptivity remain largely unresolved. New technology using microarrays for gene expression profiling and progesterone receptor polymorphism may shed more light in the near future. SUMMARY Giant strides have been made in studying the causative factors of implantation failure, but these have not been matched by therapeutic solutions. Many proposed interventions are of unproven value, yet can have harmful side-effects.

Preimplantation genetic screening of embryos for chromosome abnormalities reduces the success rate of in vitro fertilisation (IVF) by nearly a third in older women, according to a European study ( New England Journal of Medicine 2007;356:9-17). The study looked at the rates of ongoing pregnancies and live births in a total of 408 women aged 35 to 41 years undergoing a total of 862 cycles of in vitro fertilisation. Half of the women (206) were randomised to undergo preimplantation genetic screening, and the other half were a control group and were not screened. Screening involved taking a biopsy of one cell at three days and testing chromosomes to detect trisomies or other abnormalities in chromosome number. Sebastiaan Mastenbroek, from the Center for Reproductive Medicine at the University of Amsterdam, the Netherlands, and lead author of the study, explained the rationale, “Pregnancy rates in women of advanced maternal age undergoing IVF are disappointingly low. A potential cause is the increased incidence of chromosomal abnormalities. It has been suggested that use of preimplantation screening of cleavage stage embryos for aneuploidies may improve the effectiveness of …

The utility of using psychological assessments as a basis for predicting pain relief after electrode implantation is examined. Two raters independently reviewed the functional pain protocols of chronic pain patients who were candidates for deep brain (n = 13) or spinal cord (n = 17) electrode implants and predicted whether each would have a good or poor treatment response. At follow-up, five deep brain (39%) and four spinal cord (24%) patients were classified as having good responses to treatment. Predictions of outcome based on psychological data were accurate for 80% of the patients. These results suggest that functional pain assessment is useful as a part of preimplantation screening and emphasize the importance of psychological factors in the outcome of treatment for chronic pain.