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991.
Schmidt P Pruggmayer M Steinborn A Schippert C Staboulidou I Hillemanns P Scharf A 《Archives of gynecology and obstetrics》2007,276(3):259-262
Introduction First-trimester screening according to Nicolaides uses maternal age to obtain a common background risk for trisomy 21. The
likelihood ratios by nuchal translucency, free β-human chorionic gonadotropin and pregnancy-associated plasma protein-A are
not with respect to maternal age. It was the aim of this study to investigate if likelihood ratios should better take care
of it.
Materials Pearson’s correlation and different models of regression analysis had been performed on the results of 8,116 first-trimester
screenings. The total number of pregnancies was subdivided into three subgroups of healthy fetuses (n = 8,038); fetuses with Down’s syndrome (n = 46) and fetuses with other genetic abnormalities (n = 32). Statistical testing was applied to each of the three groups.
Results Strong independence from maternal age could be found for each of the first-trimester screening measurement parameter, as well
for healthy and as for affected fetuses. Neither Pearson’s test nor nonlinear regression models could detect a correlation.
Accordingly significance of Pearson’s test is not given.
Discussion First-trimester screening would not be improved by considering the maternal age in the calculation of the likelihood ratios.
Therefore the currently used algorithm is adequate. According, to the results, it seems to be proper as well to disregard
the maternal age in newer test strategies advanced first-trimester screening (AFS) at all. 相似文献
992.
Hermans C 《Archives of gynecology and obstetrics》2007,276(3):271-276
Backgroud Hereditary angioedema (HAE) is a rare genetic disorder caused by a deficiency of the plasma protein C1 inhibitor (C1-INH).
HAE is characterised by the onset of angioedema, which may develop in one or several organs, and may last from a few hours
to several days. Oedema of the upper airway can be life-threatening. As a result of hormonal changes, some women experience
more frequent angioedema attacks during pregnancy. During pregnancy, antifibrinolytic agents should only be used with caution,
and attenuated androgens are contraindicated; therefore, replacement therapy with C1-INH concentrate represents one of few
therapeutic options, but it is not widely documented.
Case study We report the first case study of the successful management with regular infusions of C1-INH concentrate, of two successive
pregnancies in a patient with HAE. During the second half of the first pregnancy, C1-INH was administered on demand at home.
For the second pregnancy, on demand treatment was intensified to prophylactic therapy, with once or twice weekly infusions
from the middle of the second trimester in order to efficiently control the frequent attacks.
Conclusions This report illustrates that HAE can be successfully managed during pregnancy with C1-INH infusions at home. Since the number
of crises may vary between pregnancies, the treatment regimen must be adapted to the patient’s need. 相似文献
993.
Srivastava G Pilkington A Nallala D Polson DW Holt E 《Archives of gynecology and obstetrics》2007,276(5):555-557
Objective Ogilvies syndrome (OS) is a rare condition in obstetrics but occurs most commonly after caesarean section. Mortality rates
from OS can be as high as 36–50% when bowel perforation or ischemia develops which highlights the early recognition of this
condition. Early diagnosis is therefore essential to prevent serious morbidity and mortality.
Conclusion We, therefore report a case of OS after caesarean section in which early detection by senior clinicians resulted in successful
management of the condition and an excellent outcome. 相似文献
994.
Araujo Júnior E Guimarães Filho HA Pires CR Nardozza LM Moron AF Mattar R 《Archives of gynecology and obstetrics》2007,275(1):5-11
BACKGROUND: To validate the prediction equation of the volume of fetal cerebellum by three-dimensional ultrasonography determined for Taiwan's population in Brazilian population. METHODS: A longitudinal prospective study was performed with 52 normal pregnant women between 20 and 32 weeks. The measurement of fetal cerebellar volume was done by virtual organ computer-aided analysis (VOCAL) method, with a rotation angle of 30 degrees. To establish the correlation of fetal cerebellar volume with gestational age, a polynomial regression analysis was performed, with cerebellar volume as dependent variable and gestational age as independent variable. To compare the prediction equation of the volume of fetal cerebellum in Taiwan's population and the equation established in this study, with the values obtained from Brazilian population (referential), we used the intraclass correlation coefficient, with the averages compared by paired Student's t test. RESULTS: The volume of fetal cerebellum was highly correlated with gestational age, and the best prediction equation obtained was of the second degree. The equation established in this study predicted cerebellar volumes more accurately than the equation established for Taiwan's population, since the average values of fetal cerebellar volume were more similar to the average values of reference. CONCLUSIONS: The equation established for Taiwan's population presented less accuracy in Brazilian population, possibly due to the strong ethnical differences between both populations. 相似文献
995.
996.
997.
Heng BC 《Journal of assisted reproduction and genetics》2007,24(4):107-109
Pertinent ethical and legal issues in the international transaction of donor sperm and eggs are discussed. Firstly, there
may be legislative and ethical “contradiction” by the local health authority in permitting import of donor gametes, due to
varying policies on donor reimbursement in different countries. This is particularly significant in countries where the underlying
principle of gamete donation is altruistic motivation, and where reimbursement is given only for direct “out-of-pocket” expenses
i.e. traveling costs. Secondly, there is a lack of clear and coherent internationally-binding legislation and regulatory guidelines
overseeing the exchange of donor gametes across international borders. In particular, provisions should be made for donor
traceability if gametes are sourced from abroad. Thirdly, in the case of “frozen-egg donation” from abroad, patients must
rightfully be informed that current cryopreservation technology is still sub-optimal, and all studies have consistently shown
that the chances of conception are always lower with “frozen-eggs” compared to freshly-retrieved eggs. Finally, regulatory
safeguards should be put in place to prevent fertility clinics and medical professionals from “re-selling” imported donor
gametes at a profit to the patient, since it would be thoroughly unprofessional for them to earn a profit simply through the
‘brokerage’ of donated human material. 相似文献
998.
Torry DS Leavenworth J Chang M Maheshwari V Groesch K Ball ER Torry RJ 《Journal of assisted reproduction and genetics》2007,24(7):303-315
Problem Implantation failure and early pregnancy loss are common following natural conceptions and they are particularly important
clinical hurdles to overcome following assisted reproduction attempts. The importance of adequate vascular development and
maintenance during implantation has recently become a major focus of investigation.
Materials and methods Review of current published literature was undertaken to summerize the cells and cell products that regulate tissue vascularity
during implantation.
Results Vascular development at the maternal fetal interface can be regulated by a number of different cell types; two principal candidates
are trophoblast and natural killer cells. A wide range of soluble factors, some with well established angiogenic functions
as well as other more novel factors, can contribute to vascular development and maintenance at the maternal–fetal interface.
Conclusions Robust vascular development occurs during implantation and early placentation of normal pregnancies. Studies to define the
extent and mechanisms by which defects in vascularity contribute to human implantation failure and early miscarriage need
to be undertaken.
Vascular development during implantation is mediated by numerous cell types and cell products and aberrant vascularity likely
contributes to implantation failure and early pregnancy loss. 相似文献
999.
Purpose To provide more genetic information about meiotic segregation behavior and the possibility of interchromosomal effects (ICE)
in spermatozoa from carriers of Robertsonian (Rob) translocations.
Materials and methods Meiotic segregation behavior in spermatozoa from six carriers of Rob translocations, four t(13;14), one t(14;22) and one t(13;21),
was investigated by dual fluorescence in-situ hybridization (FISH). Aneuploidy for chromosomes 18, X and Y was studied by
triple FISH.
Results The rate of normal/balanced spermatozoa resulting from alternate segregation ranged from 78.14 to 86.88%. The frequency of
unbalanced spermatozoa resulting from adjacent segregation varied between 11.70 and 19.53%. The higher frequencies of aneuploidy
for sex chromosome were observed in three Rob translocation carriers. In addition, the increased rates of diploid were found
in two t(13;14) carriers.
Conclusions Alternate segregation is dominant in the different types of Rob translocations. Some carriers may be at an increased risk
for ICE.
Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An increased aneuploidy for sex chromosome observed in three Robertsonian translocation carriers suggests that an interchromosomal
effect is likely in some carriers. 相似文献
1000.
Arslan M Bocca S Arslan EO Duran HE Stadtmauer L Oehninger S 《Journal of assisted reproduction and genetics》2007,24(4):111-117
Purpose: To investigate the effect of the cumulative exposure to estradiol (E2) during the follicular phase on IVF outcome.
Methods: Patients were stimulated with recombinant FSH after GnRH agonist suppression and had a day 3-embryo transfer. Estrogen exposure
was determined as the area under the curve (AUC) for serum E2 levels measured from the first day of stimulation through the day after hCG administration.
Results: E2 AUC thresholds for 10th and 90th percentiles were 4704 pg/ml and 16338 pg/ml, respectively. The pregnancy and implantation
rates were highest in the 10th–90th percentile group, and were statistically higher in this group than in the >90th percentile
group (54.6% vs. 33.3% and 24.8% and 12.9%, respectively, for pregnancy and implantation rates, P < 0.05). Recovered mature oocytes, fertilization, and number and mean score of transferred embryos were similar.
Conclusions: High cumulative E2 exposure during the follicular phase of IVF cycles has detrimental effects on implantation. 相似文献