Immunology of term and preterm labor. (1/221)

During pregnancy there is an alteration in maternal immunity within the uterus where innate, proinflammatory immune responses are tightly regulated to prevent immunological rejection of the fetal allograft. Disruption of the delicate balance of cytokines by bacteria or other factors increases the production of proinflammatory cytokines at the maternal-fetal interface and activates the parturition mechanism prematurely. Despite years of searching, there is still no broadly effective strategy for preventing preterm labor and most therapies are directed at inhibiting myometrial contractions and improving neonatal outcome. Recent studies with progestins and interleukin-10 (IL-10), however, are showing promise in randomized clinical trials and animal studies. Furthermore, the identification of the Toll-like receptors as upstream mediators of inflammation may offer alternative therapeutic targets for preventing this common pregnancy complication.  (+info)

What is the most relevant standard of success in assisted reproduction? Is BESST (birth emphasizing a successful singleton at term) truly the best? (2/221)

There is much variability and no consensus on the definition of the most relevant outcome parameter after assisted reproduction technology (ART). Descriptive reports, such as annual statistics from national registries on the success of ART programmes, should present treatment success in terms of live birth per ovarian stimulation started, as this is the most relevant information for patients and doctors alike. Addressing concerns about the high rate of multiple pregnancies, rescaling the outcome of ART in large programmes and national audits to the singleton, live birth, might trigger a global change of attitude towards elective single embryo transfer in addition to any legal restrictions imposed. For clinical studies, the outcome measure will depend on the hypothesis tested, and investigators should remain free to choose the appropriate primary outcome measure.  (+info)

What is the most relevant standard of success in assisted reproduction? Should BESST really be the primary endpoint for assisted reproduction? (3/221)

A major problem in IVF procedures is a high rate of induced iatrogenic complications including multiple gestations. Until now, transfer of at least three embryos followed by the subsequent elective reduction of triplet or higher order gestations to twins, single embryo transfer (SET) with cryopreservation of the remaining embryos, as well as the application of SET in unstimulated cycles, serves to illustrate the diversity characterizing the worldwide effort of achievement of pregnancy that aims to avoid possible complications. The BESST (birth emphasizing a successful singleton at term) endpoint constitutes an interesting parameter imposing the safety of SET. However, the observed success rate (11.1%) requires elucidation of the specific pattern of endometrial behaviour around the implantation window as well as its involvement in the further support of gestation. Consequently, research has to focus primarily on the improvement of technical parameters to achieve an acceptable success rate during the IVF procedures as compared with spontaneous gestations.  (+info)

What is the most relevant standard of success in assisted reproduction? The next step to improving outcomes of IVF: consider the whole treatment. (4/221)

Changing the way in which successful IVF treatment is defined offers a tool to improve efficacy while reducing costs and complications of treatment. Crucial to this paradigm shift is the move away from considering outcomes in terms of the single IVF cycle, and towards the started IVF treatment as a whole. We propose the most informative end-point of success in IVF to be the term singleton birth rate per started IVF treatment (or per given time period) in the overall context of patient discomfort, complications and costs. These end-points are important not only for patients, but also for clinicians, health economists and policy makers. Such an approach would encourage the development of patient-friendly and cheaper stimulation protocols with less stress, discomfort and side effects. The combination of mild ovarian stimulation with single embryo transfer may provide the same overall pregnancy rate per total IVF treatment, achieved in the same amount of time for similar direct costs, but with reduced patient stress and discomfort, and the near complete elimination of multiple pregnancies. This would offer major health and indirect cost benefits. If IVF success rates were to be expressed in terms of delivery of a term single baby per IVF treatment (or in a given treatment period), the introduction of single embryo transfer on a large scale would be facilitated.  (+info)

Comparison of misoprostol and dinoprostone for elective induction of labour in nulliparous women at full term: a randomized prospective study. (5/221)

BACKGROUND: The objective of this randomized prospective study was to compare the efficacy of 50 mcg vaginal misoprostol and 3 mg dinoprostone, administered every nine hours for a maximum of three doses, for elective induction of labor in a specific cohort of nulliparous women with an unfavorable cervix and more than 40 weeks of gestation. MATERIAL AND METHODS: One hundred and sixty-three pregnant women with more than 285 days of gestation were recruited and analyzed. The main outcome measures were time from induction to delivery and incidence of vaginal delivery within 12 and 24 hours. Admission rate to the neonatal intensive care unit within 24 hours post delivery was a secondary outcome. RESULTS: The induction-delivery interval was significantly lower in the misoprostol group than in the dinoprostone group (11.9 h vs. 15.5 h, p < 0.001). With misoprostol, more women delivered within 12 hours (57.5% vs. 32.5%, p < 0.01) and 24 hours (98.7% vs. 91.4%, p < 0.05), spontaneous rupture of the membranes occurred more frequently (38.8% vs. 20.5%, p < 0.05), there was less need for oxytocin augmentation (65.8% vs. 81.5%, p < 0.05) and fewer additional doses were required (7.5% vs. 22%, p < 0.05). Although not statistically significant, a lower Caesarean section (CS) rate was observed with misoprostol (7.5% vs. 13.3%, p > 0.05) but with the disadvantage of higher abnormal fetal heart rate (FHR) tracings (22.5% vs. 12%, p > 0.05). From the misoprostol group more neonates were admitted to the intensive neonatal unit, than from the dinoprostone group (13.5% vs. 4.8%, p > 0.05). One woman had an unexplained stillbirth following the administration of one dose of dinoprostone. CONCLUSIONS: Vaginal misoprostol, compared with dinoprostone in the regimens used, is more effective in elective inductions of labor beyond 40 weeks of gestation. Nevertheless, this is at the expense of more abnormal FHR tracings and more admissions to the neonatal unit, indicating that the faster approach is not necessarily the better approach to childbirth.  (+info)

Isolation of multipotent cells from human term placenta. (6/221)

Current sources of stem cells include embryonic stem cells (ESCs) and adult stem cells (ASCs). However, concerns exist with either source: ESCs, with their significant ethical considerations, tumorigenicity, and paucity of cell lines; and ASCs, which are possibly more limited in potential. Thus, the search continues for an ethically conducive, easily accessible, and high-yielding source of stem cells. We have isolated a population of multipotent cells from the human term placenta, a temporary organ with fetal contributions that is discarded postpartum. These placenta-derived multipotent cells (PDMCs) exhibit many markers common to mesenchymal stem cells--including CD105/endoglin/SH-2, SH-3, and SH-4--and they lack hematopoietic-, endothelial-, and trophoblastic-specific cell markers. In addition, PDMCs exhibit ESC surface markers of SSEA-4, TRA-1-61, and TRA-1-80. Adipogenic, osteogenic, and neurogenic differentiation were achieved after culturing under the appropriate conditions. PDMCs could provide an ethically uncontroversial and easily accessible source of multipotent cells for future experimental and clinical applications.  (+info)

Are the risk factors for SIDS different for preterm and term infants? (7/221)

BACKGROUND: Mortality from SIDS has declined since the recommendation that infants are not placed prone to sleep. SIDS mortality is higher in infants born preterm than those born at term. AIM: To determine if risk factors for SIDS are any different for preterm and term infants. METHODS: Mortality data over time were used to determine whether the reduction in SIDS mortality rates had occurred equally in term and preterm infants. Data from two New Zealand studies (a case-control study and a case-cohort study) were used to determine if any differences existed in risk factors for SIDS between term and preterm infants before and after the SIDS prevention campaign. RESULTS: SIDS mortality appears to have decreased by similar proportions in term and preterm infants. Risk factors for SIDS were similar in preterm and term infants, except for parity where there was a significant interaction. Increasing parity was a risk factor for SIDS in term infants but not preterm infants. CONCLUSION: SIDS rates have decreased at comparable rates in term and preterm infants, but preterm birth still remains a risk factor for SIDS. The magnitude of the odds ratios associated with modifiable risk factors were similar for both groups. There may however be a difference in risk associated with parity between term and preterm infants. The messages for risk factors for SIDS are applicable to mothers of preterm as well as term infants.  (+info)

Axial and radial diffusivity in preterm infants who have diffuse white matter changes on magnetic resonance imaging at term-equivalent age. (8/221)

OBJECTIVE: Diffuse excessive high signal intensity (DEHSI) is observed in the majority of preterm infants at term-equivalent age on conventional MRI, and diffusion-weighted imaging has shown that apparent diffusion coefficient values are elevated in the white matter (WM) in DEHSI. Our aim was to obtain diffusion tensor imaging on preterm infants at term-equivalent age and term control infants to test the hypothesis that radial diffusivity was significantly different in the WM in preterm infants with DEHSI compared with both preterm infants with normal-appearing WM on conventional MRI and term control infants. METHODS: Diffusion tensor imaging was obtained on 38 preterm infants at term-equivalent age and 8 term control infants. Values for axial (lambda1) and radial [(lambda2 + lambda3)/2] diffusivity were calculated in regions of interest positioned in the central WM at the level of the centrum semiovale, frontal WM, posterior periventricular WM, occipital WM, anterior and posterior portions of the posterior limb of the internal capsule, and the genu and splenium of the corpus callosum. RESULTS: Radial diffusivity was elevated significantly in the posterior portion of the posterior limb of the internal capsule and the splenium of the corpus callosum, and both axial and radial diffusivity were elevated significantly in the WM at the level of the centrum semiovale, the frontal WM, the periventricular WM, and the occipital WM in preterm infants with DEHSI compared with preterm infants with normal-appearing WM and term control infants. There was no significant difference between term control infants and preterm infants with normal-appearing WM in any region studied. CONCLUSIONS: These findings suggest that DEHSI represents an oligodendrocyte and/or axonal abnormality that is widespread throughout the cerebral WM.  (+info)