View clinical trials related to Placenta; Implantation.
Filter by:The investigators speculate that ultrasound examination in the first trimester can accurately detect placental location. By performing both transabdominal ultrasound and later hysteroscopy on women with a first trimester missed abortions and comparing the ultrasound findings to those of the hysteroscopy the investigators will evaluate the performance of the ultrasound in detecting the placenta location.
Placenta Adhesion Abnormalities (PAA) are the consequence of an excessive invasion of the placenta within the myometrium. PAA are related to severe maternal pregnancy outcomes, especially in case of incidental discovery during delivery that increase the risk of intraoperative massive bleeding, hysterectomy and even maternal death. Ultrasound is the standard modality for diagnosing PAA, but Magnetic Resonance Imaging (MRI) has been increasingly performed in the case of inconclusive sonographic findings. However, standard morphological MRI sequences appear as insufficient to improve the sensitivity and specificity values for detecting PAA, while quantitative MRI may be more efficient. The main objective of this study is to characterize the diagnostic performance of quantitative MRI parameters (mainly Apparent Diffusion Coefficient, T2 and T2*) reflecting placental perfusion and/or oxygenation at high field, without injection of gadolinium-based agent, for the detection of PAA in women with ongoing pregnancy between 30 and 38 weeks of gestation with risk factors for PPA.
Embryo adhesion and placentation depend on tissue plasminogen activator (tPA)-mediated activation of brain-derived neurotrophic factor, vascular endothelial growth factor and other growth factors, formation of hemidesmosomes, and degradation of extracellular matrix and basement membrane, either directly or by activating matrix metalloproteinases. Since glucose and insulin stimulate release of a major tPA inhibitor by endothelial cells - plasminogen activator inhibitor (PAI)-1 - the investigators hypothesized that lifestyle interventions proven effective in maintaining glucose and insulin levels within the normal range would increase the take home baby rate in women undergoing assisted reproduction.
In a conventional in vitro fertilization (IVF) cycle, daily microscopic observation of embryos outside the incubator to assess their morphology and establish a selection process is performed. In this way it is possible to know which embryo or embryos have greater implantantion capacity and will be transferred to the uterus to obtain a viable pregnancy. However, these observations can produce deleterious effects on embryo development due to changes in temperature, pH and osmolarity of the culture media, as well as a negative effect of direct light microscope for observation. This project aims to test the hypothesis that non-embryonic observation produces a beneficial effect on embryo quality until day 5 of development (blastocyst stage) and, therefore, on rates of implantation and ongoing gestation, compared with the conventional protocol of observations under the inverted microscope on days two, three and five of development.
The objective of study is to assess the possible impact of assisted hatching on the implantation, pregnancy rate and delivery rate after transfer of vitrified-warmed human embryos.
The successful hatching process is a prerequisite for implantation. Freezing/thawing cycles can impair the hatching process by introducing changes in the composition of the zona pellucida. The purpose of this study is to test the hypothesis that the implantation rate per embryo and the clinical pregnancy rate per embryo transfer is higher after embryo transfer of frozen-thawed embryos with opened or thinned ZP after assisted hatching when compared to embryo transfer of frozen-thawed embryos without assisted hatching. All patients starting a thawing cycle (with frozen embryos on d1-d2-d3-d5) can be included in this RTC study. Assisted hatching will be performed with a non-contact 1.48 diode laser system (MTG, Germany).