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Providence, RI, United States

Paepe M.E.D.,Women and Infants Hospital | Paepe M.E.D.,Brown University
Seminars in Perinatology | Year: 2015

Twin birth rates have increased dramatically over the past three decades, and twins currently account for 3% of all pregnancies. Twin pregnancies of any type are at risk for prematurity. In addition, monochorionic twin pregnancies (25-30% of all twin pregnancies) are predisposed to a specific set of complications, including twin-to-twin transfusion syndrome (TTTS), twin reversed arterial perfusion syndrome (TRAP), malformations, and intertwin growth discordance. This article reviews the basic mechanisms underlying the twinning process, the relationship between zygosity and chorionicity, and the various types of twinning. We describe the major complications of monochorionic twinning in association with their reported placental characteristics (or lack thereof). Finally, a rational, evidence-based approach to examination of the twin placenta is presented. It is essential for the pathologist to understand the value, strengths, and limitations of examination of the twin placenta in order to provide a meaningful clinicopathological correlation in complicated (monochorionic) twin pregnancies. © 2014 Elsevier Inc. Source

Vohr B.,Women and Infants Hospital
Clinics in Perinatology | Year: 2013

At present, moderate preterm (MPT) infants born at 32 to 33weeks' gestation and late preterm (LPT) infants born at 34 to 36weeks' gestation make up the largest subgroup of preterm infants and contribute to more than 80% of premature births in the United States. There is increasing evidence that both MPT and LPT infants are at increased risk of neurologic impairments, developmental disabilities, school failure, and behavior and psychiatric problems. Population studies suggest that for each 1week decrease in gestational age below 39weeks, there are stepwise increases in adverse outcomes after adjusting for confounders. © 2013 Elsevier Inc. Source

Maccani M.A.,Brown University | Padbury J.F.,Women and Infants Hospital | Marsit C.J.,Brown University
PLoS ONE | Year: 2011

Background: Novel research has suggested that altered miRNA expression in the placenta is associated with adverse pregnancy outcomes and with potentially harmful xenobiotic exposures. We hypothesized that aberrant expression of miRNA in the placenta is associated with fetal growth, a measurable phenotype resulting from a number of intrauterine factors, and one which is significantly predictive of later life outcomes. Methodology/Principal Findings: We analyzed 107 primary, term, human placentas for expression of 6 miRNA reported to be expressed in the placenta and to regulate cell growth and development pathways: miR-16, miR-21, miR-93, miR-135b, miR-146a, and miR-182. The expression of miR-16 and miR-21 was markedly reduced in infants with the lowest birthweights (p<0.05). Logistic regression models suggested that low expression of miR-16 in the placenta predicts an over 4-fold increased odds of small for gestational age (SGA) status (p = 0.009, 95% CI = 1.42, 12.05). Moreover, having both low miR-16 and low miR-21 expression in the placenta predicts a greater increase in odds for SGA than having just low miR-16 or miR-21 expression (p<0.02), suggesting an additive effect of both of these miRNA. Conclusions/Significance: Our study is one of the first to investigate placental miRNA expression profiles associated with birthweight and SGA status. Future research on miRNA whose expression is associated with in utero exposures and markers of fetal growth is essential for better understanding the epigenetic mechanisms underlying the developmental origins of health and disease. © 2011 Maccani et al. Source

Wenstrom K.D.,Women and Infants Hospital
American Journal of Obstetrics and Gynecology | Year: 2014

The Food and Drug Administration and Environmental Protection Agency recently issued an updated draft of advice on fish consumption for pregnant and breastfeeding women, after survey data indicated that the majority of pregnant women do not eat much fish and thus may have inadequate intake of the omega 3 fatty acids eicosapentaenoic acid [EPA] and ducosahexaenoic acid [DHA]. Omega 3 fatty acids are essential components of membranes in all cells of the body and are vitally important for normal development of the brain and retinal tissues (especially myelin and retinal photoreceptors) and for maintenance of normal neurotransmission and connectivity. They also serve as substrates for the synthesis of a variety of antiinflammatory and inflammation-resolving mediators, favorably alter the production of thromboxane and prostaglandin E2, and improve cardiovascular health by preventing fatal arrhythmias and reducing triglyceride and C-reactive protein levels. Maternal ingestion of adequate quantities of fish (defined in many studies as at least 340 g of oily fish each week) has been associated with better childhood IQ scores, fine motor coordination, and communication and social skills, along with other benefits. Although the FDA did not clarify which fish to eat, it specifically advised against eating fish with the highest mercury levels and implied that fish with high levels of EPA and DHA and low levels of mercury are ideal. The FDA draft did not recommend taking omega 3 fatty acid or fish oil supplements instead of eating fish, which is advice that may reflect the fact that randomized controlled trials of DHA and EPA or fish oil supplementation generally have been disappointing and that the ideal daily dose of DHA and EPA is unknown. It seems safe to conclude that pregnant and nursing women should be advised to eat fish to benefit from naturally occurring omega 3 fatty acids, to avoid fish with high levels of mercury and other contaminants, and, if possible, to choose fish with high levels of EPA and DHA. © 2014 Elsevier Inc. Source

De Paepe M.E.,Women and Infants Hospital
Experimental lung research | Year: 2010

Preterm infants exposed to oxygen and mechanical ventilation are at risk for bronchopulmonary dysplasia (BPD), a multifactorial chronic lung disorder characterized by arrested alveolar development and nonsprouting, dysmorphic microvascular angiogenesis. The molecular regulation of this BPD-associated pathological angiogenesis remains incompletely understood. In this study, the authors used focused microarray technology to characterize the angiogenic gene expression profile in postmortem lung samples from short-term ventilated preterm infants (born at 24 to 27 weeks' gestation) and age-matched control infants. Microarray analysis identified differential expression of 13 of 112 angiogenesis-related genes. Genes significantly up-regulated in ventilated lungs included the antiangiogenic genes thrombospondin-1, collagen XVIII alpha-1, and tissue inhibitor of metalloproteinase-1 (TIMP1), as well as endoglin, transforming growth factor-alpha, and monocyte chemoattractant protein-1 (CCL2). Increased expression of thrombospondin-1 in ventilated lungs was verified by real-time polymerase chain reaction (PCR) and immunolocalized primarily to intravascular platelets and fibrin aggregates. Down-regulated genes included proangiogenic angiogenin and midkine, as well as vascular endothelial growth factor (VEGF)-B, VEGF receptor-2, and the angiopoietin receptor TEK/Tie-2. In conclusion, short-term ventilated lungs show a shift from traditional angiogenic growth factors to alternative, often antisprouting regulators. This angiogenic shift may be implicated in the regulation of dysmorphic angiogenesis and, consequently, deficient alveolarization characteristic of infants with BPD. Source

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