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991.
OBJECTIVE: Complex evaluation of the functional system "mother-placenta-fetus" in intrauterine growth restriction (IUGR) for the prognosis of risk of perinatal complications and optimization of choice of method of delivery. METHODS: We created an objective scale for the evaluation of pregnancies complicated by IUGR using 19 fetometric, dopplerometric and pulsometric parameters. We prospectively followed 130 fetuses classified into three risk groups determined by our prognostic scale with a control group of 25. Operative method of delivery was recommended for medium and high risk groups. We examined newborns with the help of neurosonography and compared them to 139 retrospective newborns classified into three groups according to severity of IUGR with a control group of 25. RESULTS: C-sections were higher by 27 and 12% in the prospective medium and high risk groups. Ventriculomegaly, brain edema, hemorrhages and pathological vascular pulsation decreased by 9, 27, 12 and 21%. Perinatal mortality decreased by 4%. CONCLUSIONS: The developed IUGR prognostic scale optimized the choice of method of delivery and led to decreased rates of neurological morbidity and mortality in newborns with IUGR. 相似文献
992.
Sadan O Leshno M Gottreich A Golan A Lurie S 《Archives of gynecology and obstetrics》2007,276(5):517-521
Objective A previous decision analysis models for two strategic choices for trial of labor or repeated cesarean after prior cesarean
concluded that the degree of wish for an additional future pregnancy appeared to be a major determinant for choice between
the two strategic options. We had extended the analysis model to stillbirth and hypoxic-ischemic encephalopathy in addition
to placental complications while updating most of the outcomes in the decision tree.
Study design A model was formulated using a decision tree based on reported probabilities for various outcomes and estimated utilities.
The question asked was should trial of labor or repeated cesarean be performed after a prior cesarean, with a varying desire
for an additional pregnancy. The highest expected outcome determines the preference of our model.
Results Our model favors repeated elective cesarean (0.9947) over trial of labor (0.9917) after a previous cesarean and is the preferred
approach. This approach was preferable irrespective of the probability of additional pregnancy.
Conclusion In contrary to previous models, when taking into account the occurrence of a live infant birth, birth of an infant with hypoxic-ischemic
encephalopathy stillbirth, neonatal death, abnormal placental implantation, hysterectomy and maternal death the preferred
approach for women with previous cesarean is an elective repeated cesarean rather than trial of vaginal delivery. 相似文献
993.
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
994.
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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.
Kagami M Nagai T Fukami M Yamazawa K Ogata T 《Journal of assisted reproduction and genetics》2007,24(4):131-136
Purpose: The prevalence of low birth weight (LBW) is increased in subjects born after assisted reproduction technology (ART), and
defective imprinting has frequently been identified in patients with Beckwith-Wiedermann and Angelman syndromes conceived
by ART. Thus, we examined methylation pattern in a girl born after ART who had Silver-Russell syndrome (SRS) which can be
caused by maternal uniparental disomy for chromosome 7 and by hypomethylation of the differentially methylated region (DMR)
of H19.
Methods: We examined methylation status of 31 cytosines at the CpG dinucleotides in the DMR of PEG1/MEST on 7q32.2 and 23 cytosines at the CpG dinucleotides in the DMR of H19 on 11p15, using leukocyte genomic DNA.
Results: Eight of the 31 cytosines in the patient and four of the 31 cytosines in the father were hypermethylated in the PEG1/MEST-DMR. In the H19-DMR, no abnormal methylation pattern was identified in the patient.
Conclusion: The results suggest that hypermethylation of paternally expressed genes including PEG1/MEST, which usually have growth-promoting effects, may be relevant to LBW in subjects conceived by ART.
Partial hypermethylation was identified at the differentially methylated region of paternally expressed PEG1/MEST in a girl with Silver-Russell syndrome born after in vitro fertilization. 相似文献