11/31. Very high CA 125 levels during early first trimester in three cases of spontaneous abortion with chromosomal abnormalities.Three women with very elevated, early-first-trimester CA 125 levels spontaneously aborted but not until later in the first trimester or early in the second trimester. All three products of conception showed chromosomal abnormalities. Further investigation is warranted to see if high CA 125 levels might be predictive of abnormal karyotypes.- - - - - - - - - - ranking = 1keywords = conception (Clic here for more details about this article) |
12/31. Sperm chromosome analysis to assess potential germ cell mosaicism.Human sperm chromosome complements were examined to assess the possibility that the conceptions of two children with the same chromosomal defect, del(13)(q22q32), from chromosomally normal parents were the result of a paternal germ cell mosaicism. Analysis of 216 complements, both by quinacrine banding and by measuring the relative length of chromosome 13, showed no unusual subpopulation of 13s; this decreased the likelihood of a paternal origin of the deletion. Sperm chromosomal analysis is a useful adjunct to available techniques in clinical genetics. When counseling cases involving either structural or numerical de novo chromosome abnormality, it is of importance to discuss the possibility of germ cell line mosaicism as well as to offer prenatal diagnosis for subsequent pregnancies.- - - - - - - - - - ranking = 1keywords = conception (Clic here for more details about this article) |
13/31. cryopreservation of in vitro-fertilized human embryos: histologic and cytogenetic analysis of an ectopic conceptus.In this study, 39 embryos from 17 patients were cryopreserved in a Planer R204 cell freezer using the protocol of Mohr et al. (J Vitro Fert embryo transfer 2:1-10, 1985). The procedure was modified by supplementing the cryoprotectant with 10% heat-inactivated and filtered (0.22 micron) maternal serum instead of fetal calf serum, and embryos were frozen in 500-microliter plastic straws instead of glass ampoules. After 12-25 weeks of storage in liquid nitrogen, 12 embryos from six patients were thawed at 8.0 degrees C min to room temperature, incubated in 75% maternal serum with Ham's F-10, and replaced in utero. One pregnancy occurred. The patient was a 34-year-old nulligravida with occluded fallopian tubes. A year prior, she conceived triplets from three embryos during an in vitro fertilization (IVF) cycle, but she delivered at 21 weeks and the infants did not survive. The second IVF attempt produced four embryos. Two were replaced during the IVF cycle, but they did not implant. Two were cryopreserved and replaced 25 weeks later. On day 28 after replacement, beta human chorionic gonadotropin (beta-hCG) was 4126 IU, but there was no gestational sac in utero on ultrasonographic examination. laparoscopy disclosed a right tubal pregnancy which was removed with the fallopian tube. Histological examination demonstrated normal chorionic villi. The chromosomal pattern was 46 XX by direct analysis and cell culture.- - - - - - - - - - ranking = 19.031673342774keywords = fertilization (Clic here for more details about this article) |
14/31. 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 = 19.031673342774keywords = fertilization (Clic here for more details about this article) |
15/31. Detection and interpretation of two different cell lines in triploid abortions.Among a series of 98 triploid abortions, there were four specimens with two cells lines. The detection of two clones was by Q-banding of chromosomes. Two of these four specimens were dizygotic twins, the third was either a mosaic or monozygotic twins with loss of a sex chromosome from one twin and the fourth was best explained as a chimaera which arose by fertilization of two female pronuclei by three sperms. These two unusual specimens had XYY sex chromosome complements which is rare among triploids. Two additional specimens were diagnosed clinically as possible twin pregnancies but only one cell line was identified from tissue culture. The frequency of twins was of the order of 1/33.- - - - - - - - - - ranking = 19.031673342774keywords = fertilization (Clic here for more details about this article) |
16/31. Triploid embryo after in vitro fertilization.A case of a triploid embryo (69,XXX) resulting from in vitro fertilization is reported. The pregnancy ended in spontaneous abortion 44 days after embryo transfer. The embryo showed anomalies considered typical of triploidy but molar changes were not noted. The origin of extra chromosomes was apparently maternal.- - - - - - - - - - ranking = 95.158366713869keywords = fertilization (Clic here for more details about this article) |
17/31. luteal phase inadequacy and a chromosomal anomaly in recurrent abortion.luteal phase inadequacy was diagnosed and under treatment in a patient with recurrent fetal wastage when a fourth abortion occurred. Karyotypic analysis of the products of conception revealed trisomy 16. Chromosomal abnormalities may explain subsequent abortions in patients with luteal inadequacy.- - - - - - - - - - ranking = 1keywords = conception (Clic here for more details about this article) |
18/31. Apparently non-deleted ring-1 chromosome and extreme growth failure in a mentally retarded girl.A girl, who was the product of the first recognized conception by healthy and chromosomally normal parents, and who was born 5 weeks before term with a birth weight of only 1,690 g, was found to have a ring-1 chromosome, r(1), in almost all cells analysed. A minor proportion of cells had a normal diploid chromosome complement including two regular No. 1 homologues. A few cells contained a large dicentric ring, and two monocentric ring-1 chromosomes were simultaneously observed in a few other cells. Q- and G- banding revealed the r(1) chromosome to be apparently non-deleted. The patient phenotypically resembled the three previously described human subjects with r(1) chromosomes, especially with respect to her remarkable growth failure and metal retardation. From consideration of data available on general development in subjects with an autosomal ring chromosome, it appears likely that the presence of such a ring chromosome per se in an early foetal chromosome complement may predispose to significantly retarded intrauterine and postnatal growth. Various genetical implications, including mitotic irregularities with subsequent loss of cells at division, are thought to account for the significant reduction of body mass in these patients.- - - - - - - - - - ranking = 1keywords = conception (Clic here for more details about this article) |
19/31. Two conceptions in a 45,X woman.We present a 31-year-old woman with a 45,x chromosome constitution who had had two miscarriages. This report brings to 11 the number of presumably non-mosaic Ullrich-turner syndrome patients who have achieved pregnancy. A review of the literature indicates an increased incidence of chromosome abnormalities and a high rate of fetal death in offspring of such patients. However, in light of the fertility in these patients, genetic counseling should be reevaluated and perhaps amniocentesis recommended in successful pregnancies.- - - - - - - - - - ranking = 4keywords = conception (Clic here for more details about this article) |
20/31. Ring chromosome 2 in a child with growth failure and few congenital abnormalities.A ring chromosome 2 mosaic [46,XX/46,XX,r(2)(p25q37)] was found in a newborn female with severe intrauterine growth retardation (IUGR), postnatal growth failure, and a few minor abnormalities. Psychomotor development has been normal to 19 months old. A ring chromosome 2 is present in 77.8% of the nuclei examined and is not found in the parents or a sibling. G- and R-banding reveal the break points to be p25q37. The presence of a normal cell line indicates that the chromosome abnormality arose after conception.- - - - - - - - - - ranking = 1keywords = conception (Clic here for more details about this article) |
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