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PURPOSE: The goal is to determine if variations exist between male and female blastocysts in preimplantation measurements of quality and ploidy and in vitro fertilization elective single-embryo transfer (eSET) outcomes. METHODS: A retrospective chart review was conducted from a private fertility center’s database of blastocysts undergoing preimplantation genetic testing for aneuploidy, along with details of eSET from this screened cohort. Main outcomes included preimplantation embryo quality and sex-specific eSET outcomes. RESULTS: A total of 3708 embryos from 578 women were evaluated, with 45.9% male and 54.1% female. The majority were High grade. No difference existed between embryo sex and overall morphological grade, inner cell mass or trophectoderm grade, or blastocyst transformation day. Female blastocysts had a higher aneuploidy rate than male blastocysts (P < 0.001). Five hundred thirty-nine eSETs from 392 women were evaluated, with High grade embryos more likely to have implantation (P < 0.001), clinical pregnancy (P < 0.001), and ongoing pregnancy (P = 0.018) than Mid or Low grade embryos. Day 5 blastocysts were more likely to have implantation (P = 0.018), clinical pregnancy (P = 0.005), and ongoing pregnancy (P = 0.018) than day 6 blastocysts. Male and female embryos had similar transfer outcomes, although female day 5 blastocysts were more likely to result in clinical pregnancy (P = 0.012), but not ongoing pregnancy, than female day 6 blastocysts. Male eSET outcomes did not differ by blastocyst transformation day. CONCLUSION: Male and female embryos have comparable grade and quality; however, female embryos were more likely to be aneuploid. Ongoing pregnancy rates did not differ by embryo sex. Day 5 embryos had more favorable transfer outcomes than day 6 embryos.

Unusual and consistent defects in infertility patients merit attention as these may indicate an underlying genetic abnormality, in turn necessitating tailored management strategies. We describe a case of repeated early pregnancy loss from in vivo conceptions, followed by cancelled embryo transfers after one IVF and one ICSI/PGD cycle. Following the unexpected presence of cleaved embryos at the ferti- lization check in the first IVF attempt, oocytes and embryos were subsequently analyzed in an ICSI/PGD case. Part of the oocyte cohort was fixed at retrieval for a cellular evaluation of microtubules, microfilaments and chromatin. The remaining oocytes were injected with sperm, and resultant embryos were biopsied for genetic analysis by fluorescence in situ hybridization (FISH), single-nucleotide polymorphism (SNP) microarray for 23 chromosome pairs, as well as with PCR for sex chromosomes. The presence of interphase microtubule networks and pronuclear structures indicated that oocytes were spontaneously activated by the time of retrieval. FISH revealed aneuploidy in all seven blastomeres analyzed, with all but two lacking Y chromosomes. Microarray SNP analysis showed an exclusively maternal origin of all blas- tomeres analyzed, which was further confirmed by PCR. From our multi-faceted analyses, we conclude that spontaneous activation, or parthenogenesis, was probably the pathology underlying our patient's recurrent inability to maintain a normal pregnancy. Such analyses may prove beneficial not only in diagnosing case-specific aberrations for other patients with similar or related failures, but also for furthering our general understanding of oocyte activation.

Objective To obtain embryonic molecular karyotypes from genomic DNA (deoxyribonucleic acid) isolated from blastocoel fluid (BF) and to compare these karyotypes with the karyotypes from the remaining inner cell mass (ICM) and trophectoderm (TE) of the blastocyst. Design Prospective cohort study. Setting Academic center and preimplantation genetics laboratory. Patient(s) Ninety-six donated cryopreserved embryos. Intervention(s) Embryo biopsy, BF aspiration, DNA analysis using a comparative genomic hybridization microarray (aCGH). Main Outcome Measure(s) The aCGH of a single blastomere, BF-DNA, and ICM-TE. Result(s) The BF-DNA samples resulted in a successful aCGH in 63% of cases. Discordance in karyotypes was found between the BF-DNA and the ICM-TE in 52% of cases. A total of 70% of aneusomic (mosaicism), cleavage-stage embryos differentiated into euploid blastocysts. Probabilities for diagnostic accuracy were calculated and demonstrated the following: sensitivity of 0.88 (95% confidence interval [CI]: 0.62–0.98); specificity of 0.55 (95% CI: 0.39–0.70); positive predictive value of 0.41 (95% CI: 0.25–0.60); negative predictive value of 0.92 (95% CI: 0.75–0.99). Conclusion(s) Genomic DNA from the BF can be amplified and characterized by comprehensive chromosome microarrays. The results demonstrated that aneusomic cleavage-stage embryos differentiated into euploid blastocysts, possibly using a mechanism that marginalizes aneuploid nuclei into the blastocoel cavity. In addition, owing to the high discordance between the karyotypes obtained from the BF-DNA and the ICM-TE, using BF-DNA for preimplantation genetic testing is not yet advised.

Since the first successful in vitro fertilization (IVF) cycle, there have been tremendous advancements in the technologies surrounding IVF. Specific genetic disorders such as parental chromosomal translocations or inversions and single gene mutations such as cystic fibrosis or fragile X, as well as abnormalities in the number of chromosomes, or aneuploidy, are major barriers to achieving a healthy live born infant. Preimplantation genetic diagnosis (PGD) for specific chromosomal or genetic disorders and preimplantation genetic screening (PGS) for determination of the number of chromosomes, are techniques that have been developed to prevent the uterine transfer of genetically abnormal embryos during IVF cycles. The purpose of preimplantation genetic testing (PGT), that is PGD or PGS, is to improve the likelihood of giving birth to a healthy baby.

Early embryogenesis involves a series of dynamic processes, many of which are currently not well described or understood. Aneuploidy and aneuploid mosaicism, a mixture of aneuploid and euploid cells within one embryo, in early embryonic development are principal causes of developmental failure.^1,2^ Here we show that human embryos demonstrate a significant rate of genetic correction of aneuploidy, or "genetic normalization" when cultured from the cleavage stage on day 3 (Cleavage) to the blastocyst stage on day 5 (Blastocyst) using routine in vitro fertilization (IVF) laboratory conditions. One hundred and twenty-six human Cleavage stage embryos were evaluated for clinically indicated preimplantation genetic screening (PGS). Sixty-four of these embryos were found to be aneuploid following Cleavage stage embryo biopsy and single nucleotide polymorphism (SNP) 23 chromosome molecular karyotype (microarray). Of these, 25 survived to the Blastocyst stage of development and repeat microarray evaluation was performed. The inner cell mass (ICM), containing cells destined to form the fetus, and the trophectoderm (TE), containing cells destined to form the placenta were evaluated. Sixteen of 25 embryos (64%) [95% CI: 44-80%] possessed diploid karyotypes in both the ICM and TE cell populations. An additional three Blastocyst stage embryos showed genetic correction of the TE but not the ICM and one Blastocyst stage embryo showed the reverse. Mosaicism (exceeding 5%), was not detected in any of the ICM and TE samples analyzed. Recognizing that genetic normalization may occur in developing human embryos has important implications for stem cell biology, preimplantation and developmental genetics, embryology, and reproductive medicine.1)Hassold, T. et al. A cytogenetic study of 1000 spontaneous abortions. Ann Hum Genet. 44, 151-78 (1980).2)Menasha, J., Levy, B., Hirschhorn, K., & Kardon, N.B. Incidence and spectrum of chromosome abnormalities in spontaneous abortions: new insights from a 12-year study. Genet Med. 7, 251-63 (2005).

OBJECTIVE: The endoplasmic reticulum (ER) stress is activated in response to an accumulation of unfolded protein in the lumen of the ER. ER stress is critical for cell survival, but chronic or excess ER stress can lead to apoptosis in various cell types. ER stress is known to cause various aging related diseases such as diabetics and neurodegenerative diseases. In this study, the participation of the ER stress in the postovulatory aging of oocyte was examined. DESIGN: Animal model study. MATERIALS AND METHODS: In this study, mouse oocytes released from the oviduct at 12.5 hour and 18.5 hour post-hCG were designated as ‘‘fresh’’ and ‘‘aged’’ oocytes, respectively. Experiments were done as follows: (1) Analysis of expression of BiP (chaperone induced at ER stress) level by western blotting with embryo development in the fresh oocytes, (2) Comparison of expression of BiP at protein level in the fresh and the aged oocytes, (3) Analysis of the effects by ER stress inducer, thapsigargin (Tg: calcium pump inhibitor of ER) on BiP expression and on fertilization rate and embryo development after in vitro fertilization. Animals were treated in accordance with the NIH Guide for the Care and Use of Laboratory Animals, as approved by the Animal Care and Use Committee of Yamagata University. RESULTS: (1) Expression of BiP was the highest in the MII oocytes, and decreased with embryo development after in vitro fertilization. (2) Expression of BiP in the aged oocytes was increased compared with that in the fresh oocytes. (3) Tg treated oocytes showed increase in expression of BiP, low fertilization rate and deteriorated embryo development. Furthermore, Tg treatment in the fresh oocytes deteriorated embryo quality. CONCLUSION: Expression of BiP in mouse oocyte/embryo decreased with the embryo development. The result that excessive expression of BiP in the aged oocyte was observed in association with the poor embryo development suggested that aged oocytes were exposed to excess ER stress. Because excess ER stress induced by Tg leaded low fertilization rate and poor embryo development, these data suggested that ER stress might participate in postovulatory aging process of the mouse oocyte. Supported by: This study was Supported by JSPS KAKEN research grants 20591905 to H.I.

Preimplantation Genetic Diagnosis (PGD) for aneuploidy on 381 embryos from 39 initiated cycles using Fluorescence In Situ Hybridization (FISH). W G. Kearns, James Graham, Taer Han, Kevin Richter, Michael J. Tucker, Eric Widra. Ctr for Preimplantation Genetics (CPG), Rockville, MD; Shady Grove Fertility Reproductive Science Ctr (SGFRSC), Rockville, MD; SGFRSC, Georgia Reproductive Specialists, Atlanta, GA; SGFRSC, Rockville, MD.