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This review argues that the question "What does an embryo need?" cannot be adequately answered in quantitative terms to allow the formulation of media for culturing early mammalian embryos. It can be shown experimentally that "needs" in terms of the nutrients an embryo chooses to consume, and their rates of consumption, vary widely, as they are determined by the concentration of the nutrients under consideration and other constituents in the culture medium. Similarly, it is impossible to define "needs" from knowledge of the kinetic properties of nutrient transport systems. Measurements of nutrient consumption, are, however, valuable in determining overall metabolic activity and the balance between oxidative and glycolytic metabolism, in demonstrating qualitative requirements for specific nutrients and in providing markers of normality or abnormality against which to devise methods for diagnosing embryo health. On the basis of these and other considerations, a strategy is proposed for the formulation of embryo culture media that promotes metabolism that is "quiet" rather than "active", reduces the concentrations of nutrients to match those in the Fallopian tube, selects the "quietest" embryos for transfer, and trusts the autonomy of the embryo.  相似文献   

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How long does a fetal scalp blood sample take?   总被引:1,自引:0,他引:1  
The study aim was to identify the time from a decision to perform a fetal blood sample to the result of the test being available. A total of 100 consecutive fetal scalp blood samples taken on women in labour were identified from the blood gas analysers on the delivery suite. Eighty-nine percent of attempts yielded a result. The median time taken was 18 minutes (interquartile range 12-25 minutes). In 9% of women, the result took longer than 30 minutes. This is important clinically when repeated testing is required or in the second stage when operative vaginal delivery is achievable. Furthermore, when retrospectively analysing cases with a poor outcome, the time to obtain a result needs to be taken into account when determining the time at which a baby could have been delivered.  相似文献   

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The health authorities of Stockholm county recently published a Health Technology Assessment report: "Fetal monitoring with computerized STAN analysis during labor - a systematic review" with the aim to ensure that high quality research information on costs, effectiveness and broader impact of health technologies is analysed and presented in the most efficient way for those who use, manage and work in this field. The report claims to analyse available research in relation to ST interval analysis of fetal electrocardiogram (STAN) and concludes that scientific evidence for advantages of the STAN technology for maternal and fetal outcome was insufficient and that clinical use cannot be recommended and should be restricted to research protocols. The Norwegian reference group for fetal surveillance points out that the report suffers from two insufficiencies: selection bias by not providing a complete collection of the evidence for the clinical performance of the STAN technology and, secondly, that it does not provide evidence-based alternative methods.  相似文献   

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OBJECTIVE: The purpose of this study was to determine the sensitivity and specificity for acidosis of intrapartum fetal oxygen saturation measured by reflectance pulse oximetry. STUDY DESIGN: Intrapartum fetal oxygen saturation values per labor stage were correlated with umbilical artery pH, base excess and PCO(2) by regression analysis. Receiver operating characteristic curve analysis was performed with the use of historic umbilical arterial cutoff values; a fetal oxygen saturation cutoff range with optimal sensitivity and specificity was calculated. RESULTS: Mean fetal oxygen saturation was 42.8%, over the mean 132 minutes of 107 recordings. Overall areas under the sensitivity and specificity curves were 0.77 for pH and PCO(2), decreasing sharply toward birth; all areas for base excess were poor (approximately 0.5). Depending on stage and umbilical artery parameter, fetal oxygen saturation cutoffs were 33% to 36%, with sensitivities of 0.67 to 0.8 and specificities of 0.62 to 0.90. CONCLUSION: Fetal oxygen saturation sensitivities and specificities for acidosis do not yet justify the supplementation of cardiotocography with routine reflectance pulse oximetry.  相似文献   

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OBJECTIVE: We sought to determine whether umbilical cord plasma erythropoietin levels were different in deliveries complicated by meconium passage and to determine whether this response is influenced by gestational age. STUDY DESIGN: Fetal erythropoietin levels were measured in 203 appropriately grown neonates at 37 to 43 weeks of gestation; among those, 70 had passed meconium. RESULTS: Meconium passage in the entire population was associated with elevated fetal erythropoietin levels (68 vs 31 mIU/mL; P <.001). Cord blood gases, pH, base deficit, and PO (2), as well as the 1- and 5-minute Apgar scores, were not different between the meconium and no-meconium groups. Gestational age and birth weights were significantly higher in the meconium group. Stepwise multiple regression analysis with meconium and gestational age used as the independent variables showed both meconium and gestational age to be independently associated with fetal erythropoietin levels (r = 0.356, F = 14.5; meconium, P <.001; gestational age, P <.01). CONCLUSIONS: These results suggest that meconium passage can be associated with chronic fetal hypoxia as demonstrated by elevated fetal erythropoietin levels, independent of gestational age.  相似文献   

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In the context of amplitude-integrated electroencephalography (aEEG), the term 'sleep-wake cycling' (SWC), which is frequently used by clinicians and researchers, should be changed to 'cyclicity'. SWC is a technical term that refers to the biological pattern of alternating sleeping and waking states, which is difficult to define with only aEEG and no physical parameters. Additionally, the absence of cyclicity on aEEG is a more robust reflection of the sequence of the suppressed background patterns of an aEEG following cerebral injury or dysfunction than are sleep/wake states.  相似文献   

8.

Objective

to obtain an in-depth understanding of verbal and written nutrition communication in Dutch midwifery practice.

Design, setting and participants

data were collected by recording 12 initial antenatal consultations (12 weeks into the pregnancy) with primiparous women from four Dutch midwifery practices spread over The Netherlands, followed by two semi-structured qualitative interviews with the women. The interviews were undertaken on the day after the consultation and two weeks later.

Findings

analysis of the recordings revealed that a nutrition brochure was offered in an information pack, but it was not used or referred to by the midwives. Verbally, clients were informed about healthy nutrition in general terms. Specific, personally relevant nutrition-related questions and motivators of nutrition behaviour were rarely clarified and addressed. Midwives tried to create a good relationship with their clients by being friendly, complimentary, confirmative and supportive. Women appreciated talking about nutrition with the midwife because of her expertise. The subsequent interviews with the women revealed, however, that nutrition communication took place relatively late in pregnancy at a point when women were more interested in ‘hearing the baby's heart beat’. Furthermore, clients seldom looked through the nutrition brochure at home.

Key conclusion

the provision of a nutrition brochure does not serve any real purpose.

Implications for practice

to reach optimal synergy between verbal and written nutrition communication in midwifery practice, midwives should actively refer to a nutrition brochure in addition to verbal communication. Moreover, health organisations should realise that the provision of nutrition brochures to midwives does not mean that these brochures will be used as an integral part of midwives’ nutrition communication with clients.  相似文献   

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This paper is based on an international study, HIV Prevention for Rural Youth (HP4RY) 2008-2012, designed to examine the state of, and teach about, sexual health and HIV/AIDS in Edo State, Nigeria. The paper focuses on the mixed methods used in this study, paying attention to the meaning of collaboration and participation in research in a cross-continental setting. Additionally, the paper considers the complexities of engaging in decolonizing and respectful methodological approaches in these settings. Drawing on specifics from the mixed methods and details from the relevant literature, this paper demonstrates the continued need for cross-continental decolonization and decentralized engagements, specifically when dealing with sensitive topics like sexuality and HIV/AIDS. .  相似文献   

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AIM: To assess the effectiveness of post-partum placental biopsy and frozen section evaluation in diagnosing pregnancy disorders. STUDY DESIGN: Between January and July 1998, biopsies were carried out on 100 newly delivered placentas. Biopsies were carried out using a 14-gauge needle, and frozen section evaluations were reviewed. These were compared to the standard evaluation of histological evaluation of the whole placenta sections. Specimens were evaluated by standard placental pathologic criteria. RESULTS: Villous oedema which is associated with antenatal hypoxia was observed with a sensitivity of 78%, and specificity of 97%, yielding a positive predictive value of 84% in frozen section compared to standard placental evaluation. No statistical difference was observed in the evaluation of dysmaturity, intravillous fibrin agglutination and chronic villitis between frozen sectioning and whole placenta sections. Increased syncytial knots were detected with a sensitivity of 45% and specificity of 98%. CONCLUSION: Placental biopsy by frozen sectioning might be a useful and quick method of evaluation for placental pathology. Theoretically, fetal status could be more precisely evaluated by combining prenatal placental biopsy by permanent section with conservative ante-partum well-being tests.  相似文献   

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Abstract

Objective: To test if secular growth acceleration occurs during fetal life.

Methods: ANOVA Kruskal–Wallis and Mann–Whitney U-test have been used for the biometric characteristics comparison of nowadays fetal population with those three decades ago and to test the hypothesis about the existence of secular growth acceleration during fetal life. For this purpose, we first calculated mean values of particular biometric parameters for the whole pregnancy. During the period 2002–2009 biparietal diameter, fetal length and abdominal circumference measurements in singleton uncomplicated pregnancies between 22 and 41 gestational weeks were obtained. Gestational age was estimated according to Naegele's rule and confirmed with an early ultrasound examination. Pregnancies with fetal cromosomopathies and malformations were excluded as well as those resulting in perinatal death.

Results: There were no statistically significant differences of the examined fetal biometric parameters measured by ultrasound between contemporary fetal population and those from 35 years ago.

Conclusion: Our investigation did not undoubtedly prove that significant changes of fetal biometric parameters occurred in the last three decades. It is possible that secular growth acceleration does not exist in prenatal period but also the observed time period could have been short for this phenomenon to manifest.  相似文献   

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OBJECTIVE: Several studies have noted an increased prevalence of pyelectasis in male fetuses. It is speculated that pyelectasis represents a normal physiologic variant in males, whereas its presence in females indicates an increased risk of chromosomal abnormalities. Thus, we sought to investigate the association between fetal gender and the risk of major trisomies in fetuses with pyelectasis. METHODS: Retrospective analysis of a Genzyme Genetics amniocentesis database (1995 to 2004) was performed. Specimens obtained after an ultrasonographic finding of pyelectasis were eligible for analysis. The prevalence of major trisomies (trisomy 13, 18, or 21) in male and female fetuses with pyelectasis was compared using binomial distribution. RESULTS: A total of 760,495 amniocentesis specimens were analyzed. Fetal pyelectasis was reported in 671 cases. A male predominance, with a male-to-female ratio of 2.14:1 (457 compared with 214) was statistically significant (P < .001). A major trisomy was detected in 26 male fetuses (5.7%): 18 cases of trisomy 21, 2 cases of trisomy 18, and 6 cases of trisomy 13. Nine female fetuses had a major trisomy (4.2%): 6 cases of trisomy 21 and 3 cases of trisomy 13. There was no significant difference in the overall prevalence of trisomies between male and female fetuses (P = .14). CONCLUSION: We concur with previous studies documenting a higher prevalence of pyelectasis in male fetuses. In addition, our results indicate that the prevalence of major trisomies among fetuses with pyelectasis is unlikely to be dependent on fetal gender. Thus, counseling patients with regard to the genetic implications of fetal pyelectasis should be gender independent. LEVEL OF EVIDENCE: II-2.  相似文献   

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BACKGROUND: The objective was to study fetal growth parameters in in vitro fertilization (IVF) pregnancies and to investigate the relationship between fetal growth and maternal blood pressure. METHODS: We examined 64 women, pregnant after in vitro fertilization, with repeated ultrasound examinations measuring biparietal diameter, femur length, abdominal diameter and fetal weight at 24, 30, and 36 weeks of gestation. We calculated deviations in percent from expected values in regards to biparietal diameter, femur length, abdominal diameter, and fetal weight. Blood pressure was measured every second week. RESULTS: Biparietal diameter in the study group was significantly smaller at 24 (-3.3%, 95%CI -4.4 to -2.2) and 30 (-1.4%; 95%CI -2.5% to -0.3) weeks. Femur length differed significantly on all three occasions, at 24 (-6.3%; 95%CI -7.7 to -5.1), 30 (-6.6%; 95%CI -8.0 to -5.3), and 36 (-3.9%; 95%CI; -5.0 to -2.8) weeks. Abdominal diameter demonstrated a significant deviation at 24 weeks (-1.6%; 95%CI -2.8 to -0.4). Fetal weight did not reach significant deviations at any gestational age. There was no correlation between deviation of the individual growth parameters or estimated fetal weight and elevated blood pressure. CONCLUSION: The growth pattern of in vitro fertilization pregnancies does not seem to differ from spontaneously conceived pregnancies to any appreciable extent. In the present material, no relationship between fetal growth and maternal blood pressure could be observed. We could not show that an impaired fetal growth predates the development of hypertension.  相似文献   

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Objective  The main objective of the present study was to determine whether the summer season is a risk factor for oligohydramnios, by comparing the frequency of oligohydramnios during the summer months versus its frequency during the rest of the year. Methods  A retrospective population-based study including all pregnancies of patients with oligohydramnios that delivered during the years 1988–2007 in a tertiary medical center was performed. All non-idiopathic causes for oligohydramnios were excluded from the analysis. Summer months were defined as May to August. A multiple logistic regression model was performed in order to control for confounders. Results  During the study period, there were 191,558 deliveries of which 4,335 were diagnosed with oligohydramnios. Of these, 1,553 deliveries occurred during the summer months and 2,782 deliveries occurred during the rest of the year. Higher rates of oligohydramnios were found in the summer months as compared to the rest of the year: 2.5 versus 2.1%, odds ratio (OR) = 1.18, 95% confidence interval (CI) 1.1–1.3; P < 0.001. Using a multiple logistic regression model, controlling for confounding variables such as ethnicity, the summer season was noted as an independent risk factor for oligohydramnios (OR = 1.1, 95% CI 1.02–1.21; P < 0.001). Another independent risk factor for oligohydramnios was Bedouin ethnicity (OR = 1.3, 95% CI 1.2–1.4; P = 0.015). Conclusions  Oligohydramnios is significantly more common during the summer months versus the rest of the year. Moreover, the summer season is an independent risk factor for oligohydramnios.  相似文献   

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ObjectiveAcute funisitis (AF) is most commonly associated with acute chorioamnionitis (AC) and ascending infection. The significance of cases of AF without associated AC or isolated funisitis (IF) is unknown. Our objective was to evaluate clinical and pathologic features of IF and to determine its significance.Study designThis was a retrospective review of placentas of patients delivering at our institution from 1997 to 2017. Placentas with the diagnosis of IF comprised the study population and placentas without either AF or AC served as controls.ResultsThere were 156 cases and 181 controls identified. Maternal age, gestational age, birthweight and mode of delivery were similar in both groups. 132 (84.6%) of cases of IF had meconium, with 62 (47.0%) having meconium only in the membranes, 36 (27.3%) in the membranes and cord and 34 (25.6%) in the membranes and cord with associated myonecrosis. 72 (38.7%) of controls had microscopically identified meconium, with only one (1.4%) showing meconium in the cord. None had myonecrosis (p < .001). There was also a significantly higher rate of intrauterine fetal demise (IUFD) in the IF group (p = .027). but the rate of suspected Intrauterine growth restriction (IUGR) was significantly greater in the controls (p = .014).ConclusionIF is highly associated with the presence of meconium discharge and meconium-associated myonecrosis of umbilical vessels. The inflammation in IF may be the result of damage to the muscle fibers of the cord due to meconium but additional studies are necessary to understand the significance of these findings.  相似文献   

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Objectives: To analyze in a retrospective cohort study the outcomes of pregnancies with isolated oligohydramnios at the late preterm period (34–36.6 weeks of gestation).

Study design: This retrospective cohort study included three groups of women: (1) Women with isolated oligohydramnios whose pregnancy was managed conservatively (n?=?33 births); (2) women with isolated oligohydramnios who were managed actively (i.e. induction of labor) (n?=?111 births); and (3) a control group including women with normal amount of amniotic fluid who had a spontaneous late preterm delivery (n?=?10,445 births). Maternal and fetal characteristics and obstetrics outcomes were collected from a computerized database of all deliveries at Soroka University Medical Center during the study period.

Results: Our cohort included 10,589 births. The rate of inducing labor was higher in the oligohydramnios groups compared to the controls (p?p?p?=?.026), chorioamnionitis (p?=?.01), and transitory tachypnea of the newborn (p?=?.02). After controlling for confounding factors, mal presentation (OR?=?19.9), and a prior CS (OR?=?2.4) were independently associated with an increased risk for CS, while induction of labor was associated with a reduced risk for CS (OR?=?0.28).

Conclusions: Women with late preterm isolated oligohydramnios had a higher rate of induction of labor than women with a normal amount of amniotic fluid. Induction of labor seems to be beneficial to both the neonate and the mother as seen by a lower rate of CS conducted in this group, as well as lower maternal and neonatal morbidity in comparison to the conservative group. Therefore, women with oligohydramnios at late preterm may benefit from induction of labor.  相似文献   

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