摘要:

AbstractClinical and experimental evidence indicate that PTD results from four primary pathogenic mechanisms:activation of the maternal or fetal HPA axis; amniochorionic-decidual or systemic inflammation; decidual hemorrhage;and, pathologic distention of the myometrium. Each of these four pathways has a distinct epidemiologicaland clinical profile, and unique biochemical and biophysical pathways initiating parturition, but shares acommon final biochemical pathway involving myometrial activation and stimulation, and enhanced genitaltract protease activity promoting PPROM and cervical change. Traditional methods of predicting women atrisk relying on obstetrical history or symptoms and epidemiological risk factors are neither sensitive nor specific.Recent approaches to predicting PTD, including sonographic measurement of cervical length and biochemicalassays for hCG, cytokines, fFN, MMPs, estrogens, and CRH, are more sensitive than traditionalmethods. Moreover, given the heterogeneous, interactive etiopathogeneses of PTD, multiple biochemicalmarkers should not only increase sensitivity and specificity, but also permit the detection of the relative contribution of each pathogenesis to the overall risk ofPTD.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.001

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

摘要:

AbstractThis paper reviews data that support the effectiveness of the French approach of using risk scoring for evaluatingthe risk of preterm delivery. This approach, which was developed in 1969 and spread to obstetricians andmidwives throughout France in the early 1970s, includes systematic information about the recognition ofuterine contractions, advice about reduction of physical exercise, and the prescription of work-leave for womenwith heavy or physically demanding work loads. The effectiveness of this prevention strategy is assessedusing three different data sets: an evaluation of a pre-term prevention program in the Alsace Region of France, five successive French national sample surveyswhich collected data on pregnant women, and a study of the effectiveness of a prevention program for twinsin the district of Haut de Seine near Paris. The authors show that the rate of preterm birth in France declinedsubstantially, but that the decline was concentrated among singleton spontaneous births. Since the 1970sinduced preterm births have increased, and, interventions have not reduced the high rates of preterm birthamong twins.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.002

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

摘要:

AbstractIn summary, these studies have suggested that prostaglandin dehydrogenase may have a central role to playin the mechanisms which determine biologically active prostaglandin concentrations within human fetal membranesand placenta at the time of labor, at term or preterm. Moreover, our studies indicate that the regulationof PGDH may by multifactorial (figure 3). In certain regions of the membranes, we suggest that PGDH expressionmay be influenced by levels of anti-inflammatory and pro-inflammatory cytokines. In other regionsof the membranes, we suggest that PGDH may be regulated at a transcriptional level by competing activitiesof progesterone and cortisol. The action of progesterone could be effected through systemically-derived steroid,or by locally synthesized steroid, acting in a paracrine and/or autocrine fashion. The effects of cortisol in placentamust be due to glucocorticoid derived from the maternal or fetal compartment, since the placenta lacksthe hydroxylases required for endogenous cortisol production. However, metabolism of cortisol by 11β-HSD-2 reduces the potency of this glucocorticoid in placentaltissue. In chorion however, cortisol may be formed locally, from cortisone, in addition to its being derivedfrom the maternal circulation and/or from the amniotic fluid. Our current studies do not allow us to delineatewhether the effects of progesterone and cortisol on PGDH are exerted through the glucocorticoid receptor(GR) or progesterone receptor (PR) or both. It is possible that through pregnancy, PGDH activity is maintainedby progesterone acting either through low levels of PR in membranes, or, more likely, acting throughGR. At term, elevated levels of cortisol compete with and displace progesterone from GR, resulting in inhibitionof PGDH transcription and activity. In this way, local withdrawal of progesterone action would be effectedwithin human intrauterine tissues, without requiring changes in systemic, circulating progesterone concentrations.Since glucocorticoids appear also to increase expression of prostaglandin synthesizing enzymeswithin the amnion and chorion, directly by upregulating PGHS-2, or indirectly through the intermediaryaction of a paracrine effector such as CRH, their role in coordinating processes of parturition remainscentral.Further understanding of the regulation of PGDH may be of therapeutic importance. For example, it is possiblethat PGDH activity in lower segment chorion may be reduced in those patients with premature cervical softening,or may be particularly high in those patients with an unfavorable cervix, presenting with a low Bishopscore and poor progression at the time of labor. If the enzyme in this region crucially determines the passageand availability of biologically active prostaglandins from amnion and chorion to underlying cervix, thenpharmacologic manipulation of PGDH activity may effectively regulate PG transfer in these clinical conditions.Glucocorticoids appear to have a central role in promoting production of agents that are uterotonic tomyometrial activity. It is likely that these activities explain the transient increments in uterine contractility reportedin patients receiving prenatal corticosteroids to promote fetal pulmonary maturity [11]. Recognition of this physiology suggests that careful monitoring ofthese patients is advised, and would argue further against repeated, indiscriminate, use of glucocorticoidsin patients with an inappropriate diagnosis of threatened preterm labor.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.003

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

摘要:

AbstractOur intention is to review recent data and provide recommendations for the use of antibiotics in cases of pretermlabor or preterm premature rupture of the membranes (pPROM). Various studies assessing antibioticsas treatment for preterm labor demonstrate neonatal or maternal benefits only in certain circumstances. Antibiotictreatment should be given to patients with bacterial vaginosis andTrichomonas vaginalis. Currently, antibiotics should not be applied routinely to prolong pregnancyin women with preterm labor and intact membranes. However, antibiotic therapy should be given topatients with pPROM to prolong pregnancies at 24 to 32 weeks' gestation. Our management of pPROM upto 32 weeks' gestation includes use of corticosteroids, antibiotic (extended spectrum penicillins) and tocolytictreatment for preterm labor and pregnancy prolongation. We consider expectant management previous to evidenceof intrauterine infection. In women with pPROM at 32 to 34 weeks we found it beneficial to deliver 24hours after administration of corticosteroids or, in cases of intrauterine infection, immediately. Finally, we reporton our research work regarding fetal brain development in preterm birth. Further studies will be necessary toclarify the role of the interleukin-6/interleukin-6 receptor pathway in the development of intracerebral hemorrhage frequently occuring in premature infants.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.004

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

摘要:

AbstractWe are now in the era of Evidence-based Medicine and many people involved in purchasing and supporting health care together with the general public are demanding that clinical practice be based upon sound scientific evidence of efficacy and safety. It is now possible to evaluate many interventions in perinatal medicine by examining the results of systematic reviews. For example, interventions that are effective for neonatal respiratory failure have recently been published. The practice of neonatal intensive care is approximately 90% evidence based but there is still room for improvement. Much more work needs to be done in preparing systematic reviews for the Cochrane Library. European reviewers in perinatal medicine, comprising pregnancy and childbirth and neonatology, would be welcomed. Perhaps for the new millennium we will be able to boast that the practice of perinatal medicine is totally evidence-based.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.005

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

摘要:

AbstractThe key function of the uterine cervix to maintain pregnancy is biochemically characterized by an increasedsynthesis of proteins (e. g., collagen), proteoglycans, and glycoproteins (e. g., fibronectin) as well as by defined interactions between these components of the extracellularmatrix. In contrast to the slow phase of the cervical ripening process in late pregnancy, cervical dilatation duringparturition requires the rapid production and action of catabolic enzymes leading mainly to collagen degradationand changes in its architecture but also to degradation of other fundamental matrix proteins. Evidence suggeststhat an increased production of TNF-α and IL-1β, e. g., induces a rise in the expression of endothelial adhesionmolecules with subsequent extravasation of neutrophils into the cervical stroma and that the chemotaxis and degranulationof these cells is triggered by an increased concentration of IL-8. Rising concentrations of hyaluronanat this time have been considered as potent inducers of IL-1β and TNF-α synthesis by various leukocyte populations.The increase in IL-6 synthesis stimulates prostaglandin and leukotriene production causing dilatation of cervical vessels and further promoting the extravasationof leukocytes. The proteases released after degranulation of neutrophils encounter an already destabilized collagenousfiber network. Since a sustained action of proteases may lead to severe tissue damage, this process is strictlylimited in time and is controlled by increasing concentrations of tissue inhibitors of protease in the lower uterinesegment immediately after delivery. The clinical consequences of this basic research is to develop new conceptsin a more causal treatment of cervical pathology during pregnancy and parturition.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.006

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

摘要:

AbstractAims:We have performed fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) in previable pregnanciesaffected by twin-twin transfusion syndrome (TTTS) since 1988. Treatment outcomes obtained afterthe procedure's learning curve are presented and compared to those from other centers performing FLOC orother treatment methods.Methods:A total of 100 cases of FLOC have been performed at our centers. The later 67 TTTS patients hada mean gestational age of 21.1 ± 1.7 weeks (range 18–24.5) with a mean fundal height of 33.1 ± 4.9 cm(range 27–44) when treated. Eighteen (27 %) had failed another treatment method before FLOC.Results:All 67 cases have delivered with 82% (55/67) having at least one surviving twin and 93/134 (69 %) ofthe twins surviving overall. Thirty-eight have surviving twins, 17 have one survivor (5 neonatal and 12 fetaldeaths), and 12 have none. The mean duration of pregnancy following FLOC was 9.9 ± 5.5 weeks (range1.0–19). Only 4 of 93 (4.3 %) survivors have significant handicaps at a mean follow-up of 14.3 ± 10.1 months (range 1.0–34).Conclusion:Fetoscopic laser occlusion of chorioangiopagous vessels within the vascular equator limits theduration of fetal pathophysiology in TTTS and results in neonatal outcomes superior to the modified procedureand other treatment methods.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.007

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

摘要:

AbstractIntrauterine death of one fetus in monochorionic twinning is associated with high rates of perinatal morbidityand mortality in the surviving fetus. Subsequent development of hydrops fetalis in the donor twin after fetaldemise of the recipient twin has been described in only two case reports and pathophysiology remains unclear.We report on a monochorionic-diamniotic twin pregnancy complicated by severe twin-twin transfusion syndrome. Ultrasound examination at 20 weeks of gestationshowed discrepant twins with oligohydramnios in the smaller twins' sac and polyhydramnios in that ofthe larger twin. Repeated amniocenteses permitted prolongation of the pregnancy. However, the recipient twindeveloped deteriorating hydrops fetalis and died at 28 weeks of gestation. After this event, subsequent developmentof hydrops fetalis in the surviving donor twin could be observed, as well as an increase of amnioticfluid. An elective cesarean section was performed at 29 weeks of gestation. Initial hypoxemia could be effectivelytreated by high frequency oscillatory ventilation, surfactant therapy and inotropic support. The infant wasdischarged in good condition at the age of 2 months. Although rare, antenatal demise of the recipient twin ina monochorionic pregnancy can be associated with the subsequent development of hydrops fetalis in the survivingdonor twin. We speculate that this phenomenon is due to ischemia-reperfusion injury of the previouslypoorly perfused twin.

ISSN:0300-5577    

DOI:10.1515/JPM.1999.008

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

ISSN:0300-5577    

DOI:10.1515/jpme.1999.27.1.74

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter

ISSN:0300-5577    

DOI:10.1515/jpme.1999.27.1.75

出版商:Walter de Gruyter    

年代:1999

数据来源: Degruyter