Malperfusion of the placenta has been implicated as a cause of oxidative stress in complications of human pregnancy, leading to release of proinflammatory cytokines and anti-angiogenic factors into the maternal circulation. Uterine contractions during labor are known to be associated with intermittent utero-placental perfusion. We therefore tested whether oxidative stress, proinflammatory cytokines, and angiogenic regulators were increased in placentas subjected to short (<5 hours) and long (>15 hours) labor compared with nonlabored controls delivered by cesarean section. In addition, broader changes in gene transcripts were assessed by microarray analysis. Oxidative stress, activation of the nuclear factor-kappaB pathway, tumor necrosis factor-alpha and interleukin 1beta all increased in placental tissues after labor. Stabilization of hypoxia-inducible factor-1alpha and increased vascular endothelial growth factor soluble receptor-1 were also observed. By contrast, tissue levels of placenta growth factor decreased. Apoptosis was also activated in labored placentas. The magnitude of these changes related to the duration of labor. After labor, 55 gene transcripts were up-regulated and 35 down-regulated, and many of these changes were reflected at the protein level. In conclusion, labor is a powerful inducer of placental oxidative stress, inflammatory cytokines, and angiogenic regulators. Our findings are consistent with intermittent perfusion being the initiating cause. Placentas subjected to labor do not reflect the normal in vivo state at the molecular level.
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The advent of high-resolution transvaginal ultrasound (TVS) has revolutionized our understanding of the pathophysiology and the management of early pregnancy failure. Knowledge of the ultrasound appearances of normal early pregnancy development and a good understanding of its pitfalls are essential for the diagnosis and management of early pregnancy failure. Ultrasound imaging has rapidly replaced all other techniques used to study normal human development in the first trimester, and ultrasound features of the early gestational sac have corroborated anatomical studies showing that the first structures to appear are the celomic cavity and the secondary yolk sac. No single ultrasound measurement of the different anatomical features in the first trimester has been shown to have a high predictive value for determining early pregnancy outcome. Similarly, Doppler studies have failed to demonstrate abnormal blood flow indices in the first-trimester uteroplacental circulation of pregnancies that subsequently end in miscarriage. Ultrasound parameters combined with maternal serum hormone levels, maternal age, smoking habits, obstetric history and the occurrence of vaginal bleeding have all been combined in multivariate analyses, with mixed results. Combined ultrasound and in-vitro experiments have demonstrated that the maternal circulation inside the placenta starts at the periphery at around 9 weeks of gestation and that this is associated with a physiological oxidative stress which could be the trigger for the formation of the placental membranes. Abnormal development of these membranes can result in subchorionic hemorrhage and threatened miscarriage with subsequent long-term consequences such as preterm rupture of the membranes and preterm labor, irrespective of the finding of a hematoma on ultrasound. In both euploid and aneuploid missed miscarriages there is clear ultrasound evidence for excessive entry of maternal blood at a very early stage inside the developing placenta resulting in oxidative stress and subsequent degeneration of villous tissue. The finding of blood flow in the intervillous space in cases of first-trimester miscarriage using color Doppler also appears to be useful in the prediction of success of expectant management. Miscarriages with blood flow within the intervillous space are up to four times more likely to complete with expectant management. TVS is considered the gold standard in the diagnosis and management of incomplete miscarriage. Expectant management of miscarriage, using ultrasound parameters to determine eligibility, could significantly reduce the number of unnecessary evacuations of the retained products of conception, depending on the criteria used.
Key content Torsion of the ovary, tube or both is estimated to be responsible for only a small number of all gynaecological emergencies, but is a common diagnostic challenge in the emergency setting. Diagnosis can be difficult and is mainly based on clinical symptoms and imaging techniques such as ultrasound and MRI. A normal ultrasound scan does not exclude adnexal torsion and the decision to operate should be made on clinical grounds if symptoms are severe. Treatment is traditionally surgical removal of the ovary or adnexum, however, there is increasing evidence for conservative surgery, such as de‐torsion and oophoropexy, particularly in younger women. This article provides an overview of the symptomatology, ultrasound diagnosis and classification, as well as treatment options for ovarian torsion. Learning objectives To understand the clinical presentation and ultrasound characteristics associated with ovarian torsion. To review the literature on the available surgical options. Ethical issues Oophorectomy is commonly performed for adnexal torsion with a possible negative impact on fertility in women of reproductive age. De‐torsion is a more conservative surgical approach that should be considered in all younger women with ovarian torsion.
We have previously demonstrated placentas from laboring deliveries at high altitude have lower binding of hypoxia-inducible transcription factor (HIF) to DNA than those from low altitude. It has recently been reported that labor causes oxidative stress in placentas, likely due to ischemic hypoxic insult. We hypothesized that placentas of high-altitude residents acquired resistance, in the course of their development, to oxidative stress during labor. Full-thickness placental tissue biopsies were collected from laboring vaginal and nonlaboring cesarean-section term (37–41 wk) deliveries from healthy pregnancies at sea level and at 3,100 m. After freezing in liquid nitrogen within 5 min of delivery, we quantified hydrophilic and lipid metabolites using 31P and 1H NMR metabolomics. Metabolic markers of oxidative stress, increased glycolysis, and free amino acids were present in placentas following labor at sea level, but not at 3,100 m. In contrast, at 3,100 m, the placentas were characterized by the presence of concentrations of stored energy potential (phosphocreatine), antioxidants, and low free amino acid concentrations. Placentas from pregnancies at sea level subjected to labor display evidence of oxidative stress. However, laboring placentas at 3,100 m have little or no oxidative stress at the time of delivery, suggesting greater resistance to ischemia-reperfusion. We postulate that hypoxic preconditioning might occur in placentas that develop at high altitude.
Objective To determine the clinical significance of a chorionic bump diagnosed by ultrasound in women attending an early pregnancy unit in a teaching hospital. MethodsThis was a retrospective case-control study over an 8-year period (2003-2010
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