1/8. trisomy 2 in an acardiac twin in a triplet in-vitro fertilization pregnancy.A case is reported of twin reversed arterial perfusion (TRAP) sequence in a triamniotic dichorionic triplet pregnancy conceived by in-vitro fertilization which was diagnosed at 25 weeks of gestation by colour Doppler sonography. It highlights the risk of monochorionicity-associated morbidity in multiple pregnancies obtained by assisted conception and stresses the importance of chorionicity determination by early ultrasound examination. cytogenetic analysis of skin from the acardius showed trisomy 2 in all cells, whereas the karyotype in the monochorionic triplet was normal. This is an example of heterokaryotypic monozygotism where the chromosomal abnormality must have occurred during the early cleavage divisions. aneuploidy as a possible aetiological factor of TRAP sequence is discussed.- - - - - - - - - - ranking = 1keywords = fertilization (Clic here for more details about this article) |
2/8. Selective termination of aneuploidy utilizing rapid fluorescence in situ hybridization detection techniques.Twin pregnancy following assisted reproductive technology with a euploid fetus and a coexisting aneuploid co-twin constitutes a conflicting situation; therefore, it is important for the genetic constitution of each co-twin to be diagnosed accurately and promptly for parental genetic counseling and subsequent aggressive management. A 35-year-old woman, gravida 1, with a 2-year history of infertility, presented bilateral fallopian tubal obstruction at her infertility workups, for which she received in vitro fertilization; subsequently she conceived a twin pregnancy. She underwent genetic amniocentesis at 16 weeks' gestation, as indicated by an advanced maternal age. Presented with the diagnosis of twin pregnancy with discordancy for trisomy 21, a rapid fluorescence in situ hybridization (FISH) technique for aneuploidy mapping was applied for subsequent abdominal selective fetal reduction. The FISH technique facilitates the rapid analysis of uncultured amniocytes. Normal (disomic) and trisomic samples can be distinguished clearly and rapidly for subsequent selective fetocide. The FISH technique is an important tool in prenatal diagnosis and clinical applications.- - - - - - - - - - ranking = 0.2keywords = fertilization (Clic here for more details about this article) |
3/8. Pregnancy after cryopreservation of donor oocytes and preimplantation genetic diagnosis of embryos in a patient with ovarian failure.OBJECTIVE: To describe the successful use of preimplantation genetic diagnosis to assess the prevalence of meiotic errors after oocyte cryopreservation in an oocyte donation cycle. DESIGN: Case report. SETTING: Private IVF center. PATIENT(S): A 42.6-year-old patient with ovarian failure. INTERVENTION(S): A donor oocyte IVF cycle with cryopreservation of oocytes followed by thaw, fertilization of oocytes, preimplantation genetic diagnosis for selective aneuploidy, and ET. MAIN OUTCOME MEASURE(S): Preimplantation genetic analysis of chromosomes 13,16,18, 21,22, X, and Y with fluorescence in-situ hybridization. RESULT(S): The recipient's initial serum beta-hCG level was 196 mIU/mL 15 days after oocyte retrieval. An initial ultrasound at the sixth week of gestation revealed two gestational sacs. A second ultrasound 1 week later showed a monochorionic twin in sac A and a singleton pregnancy in sac B. Fetal cardiac activity was visualized for all gestations. CONCLUSION(S): This case illustrates the feasibility of cryopreservation of donor oocytes combined with preimplantation genetic diagnosis for clinical use in those settings where there may be an increased risk of spindle-related abnormalities.- - - - - - - - - - ranking = 0.2keywords = fertilization (Clic here for more details about this article) |
4/8. Assisted reproductive technology and congenital overgrowth: some speculations on a case of Pallister-Killian syndrome.We report on a boy with Pallister-Killian syndrome (PKS) who was conceived by assisted reproductive technology (art), specifically in vitro fertilization (IVF) with parents' gametes. A prenatal diagnosis performed elsewhere by CVS failed to detect the presence of the isochromosome 12p that was demonstrated postnatally in approximately 50% of cultured skin fibroblasts. Given that the patient did not show the congenital overgrowth typical of PKS, we speculate that art might have restricted overgrowth in this particular case. More broadly, we hypothesize that overgrowth might protect from early demise fetuses conceived by art, a technology known to cause low and very low birth weight.- - - - - - - - - - ranking = 0.2keywords = fertilization (Clic here for more details about this article) |
5/8. First successful pregnancy outcome after preimplantation genetic diagnosis for aneuploidy screening in embryos generated from natural-cycle in vitro fertilization combined with an in vitro maturation procedure.OBJECTIVE: To report on the first successful pregnancy performing preimplantation genetic diagnosis (PGD) on embryos obtained after combining natural IVF with in vitro maturation procedure. DESIGN: Case report. SETTING: University hospital. PATIENT(S): A 35-year-old patient with polycystic ovaries who was attending the fertility clinic. INTERVENTION(S): in vitro maturation of immature oocytes and preimplantation genetic diagnosis. MAIN OUTCOME MEASURE(S): Preimplantation genetic diagnosis of aneuploidy screening in embryos produced from in vitro maturation procedure. RESULT(S): Thirteen immature and two mature oocytes were collected, and eight mature oocytes were normally fertilized, of which six embryos were biopsied for chromosome analysis. Two chromosomally normal embryos were transferred on day 5, resulting in the birth of a healthy child. CONCLUSION(S): This case report demonstrates that an acceptable number of embryos can be generated after in vitro maturation procedure to perform PGD for aneuploidy screening and that this approach can be extended to patients with polycystic ovaries or polycystic ovary syndrome who are undergoing PGD for other genetic diseases.- - - - - - - - - - ranking = 0.8keywords = fertilization (Clic here for more details about this article) |
6/8. Meiotic segregation of human sperm chromosomes in translocation heterozygotes: report of a t(9;10)(q34;q11) and a review of the literature.Meiotic segregation products were studied in sperm from a man who was heterozygous for a reciprocal translocation, t(9;10)(q34;q11). A total of 171 sperm chromosome complements were studied by in vitro fertilization of hamster eggs. All possible 2:2 and 3:1 meiotic segregations were observed with the following frequencies: alternate, 41%; adjacent-1, 48%; adjacent-2, 5%; 3:1, 6%. Within alternate segregations, the number of normal sperm (35) was not significantly different from the number of sperm carrying a balanced form of the translocation (33), as expected. The proportion of sperm with an unbalanced form of the translocation was 60%. There was no evidence for an interchromosomal effect, since the frequencies of numerical (8%) and structural (15%) chromosomal abnormalities (both unrelated to the translocation) were within the normal range of control donors. The literature on a total of 10 translocation heterozygotes studied by sperm chromosome analysis was reviewed.- - - - - - - - - - ranking = 0.2keywords = fertilization (Clic here for more details about this article) |
7/8. The meiotic segregation of human sperm chromosomes in two men with accessory marker chromosomes.Accessory marker chromosomes are occasionally discovered in normal individuals and they are presumed "clinically inert" since they do not appear to have any phenotypic effect. However, they do pose a theoretical risk at meiosis since they could disrupt the normal pairing and disjunction of homologous chromosomes. Sperm chromosome complements have been studied in two normal males, each of whom carry a small bisatellited accessory marker chromosome 47,XY, mar (psps), to determine if these marker chromosomes are associated with an increased frequency of aneuploid gametes. Pronuclear chromosomes were visualized after in vitro fertilization of golden hamster eggs with human sperm. The frequency of sperm complements containing a marker chromosome was not significantly different from 50% as theoretically expected, in either male (17/43 and 13/31 with marker chromosomes). One male had 2/43 (4.7%) aneuploid sperm, which is very close to the average frequency of aneuploid sperm seen in control donors (5%). The other male had 6/31 complements with chromosomal abnormalities. One set of sperm chromosomes had structural abnormalities, and five (16.1%) had numerical abnormalities. This frequency of aneuploidy is significantly elevated over the frequency seen in control donors (P = .0002). It is particularly interesting that all the abnormalities involved small chromosomes, as would be expected if the marker chromosome participated in distributive pairing and thereby disrupted normal disjunction of chromosomes of similar size. These preliminary results suggest that accessory marker chromosomes may increase the risk of aneuploid gametes in some individuals.- - - - - - - - - - ranking = 0.2keywords = fertilization (Clic here for more details about this article) |
8/8. Rapid chromosomal analysis of germ-line cells by FISH: an investigation of an infertile male with large-headed spermatozoa.A rapid fluorescence in-situ hybridization (FISH) technique was used for direct chromosomal analysis on germ cells from an infertile male with large-headed spermatozoa. The interphase chromosomes were fluorescently-labelled using an extremely bright cyanine dye during a 5-15 min FISH procedure. germ cells were analysed using a battery of chromosome-specific dna probes in several consecutive rapid FISH experiments. It was found that the majority of large-headed spermatozoa contained a diploid chromosome number probably due to errors in meiosis I or II divisions, whereas the majority of spermatozoa with normal sized heads are haploid and may be utilized for selective in-vitro fertilization procedures. Rapid FISH may be useful for the detection of major chromosomal aneuploidies in germ cells as an alternative technique to standard or multicolour FISH, and may find an additional application for the chromosomal analysis of human preimplantation embryos.- - - - - - - - - - ranking = 0.2keywords = fertilization (Clic here for more details about this article) |