Objective: The purpose of this study was to define the association between unequal placental sharing and birth weight discordance in monochorionic/diamniotic twin pregnancies. Study design: The study comprised a prosp...
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Objective: The purpose of this study was to define the association between unequal placental sharing and birth weight discordance in monochorionic/diamniotic twin pregnancies. Study design: The study comprised a prospective cohort of monochorionic/diamniotic twin pregnancies who were delivered in Kaiser Permanente-Northern California, 1997-2003. Dye injection studies of fresh postpartum placentas were performed. Placental sharing, cord insertion combinations, vascular anastomoses, gestational age, and birth weights were recorded. Statistical comparisons of birth weight and gestational age were made with the Student t test. Rates of birth weight discordance were compared with the chi-square test. Multivariate logistic regression models analyzed the relationship between variables of interest. Results: Mean birth weights for larger and smaller twins were 2400 g and 2109 g, respectively. Twenty-two percent of the monochorionic/diamniotic twin pairs had birth weight discordance ≥20%, and 8%of these pairs had twin-twin transfusion syndrome. Monochorionic/diamniotic twin pairs with unequal placental sharing had a 9.8 times greater likelihood of birth weight discordance(95%CI, 5.4-17.9) as compared with those pairs with equal placental sharing. Conclusion: Unequal placental sharing is a significant risk factor for birthweight discordance inmonochorionic/diamniotic twins. Antenatal diagnosis of unequal placental sharing would enable improved counseling in the setting of monochorionic/ diamniotic twins.
Purpose: The prognostic significance of portal venous gas (PVG) in neonatal necrotizing enterocolitis (NEC) for operative intervention (OP), neonatal complications, and mortality remains *** authors designed a long-te...
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Purpose: The prognostic significance of portal venous gas (PVG) in neonatal necrotizing enterocolitis (NEC) for operative intervention (OP), neonatal complications, and mortality remains *** authors designed a long-term prospective study to describe the natural history of PVG related to these outcomes and to test the hypothesis that PVG does not mandate ***: All infants admitted to a single center between October 1991 and February 2003 were evaluated weekly to identify all cases of NEC (defined as Bell stage II or higher).Demographic, radiological, surgical, and outcome data were abstracted *** studies were performed at the onset of illness and at subsequent 6-to 8-hour intervals or as clinically indicated.A single pediatric radiologist reviewed all *** are expressed asmean±*** ratios and relative risk ratios are reported with 95%*** level of significance was P ≤.***: After the exclusion of 24 infants with lethal diseases, major congenital or chromosomal anomalies, or recurrent episodes of NEC, 194 of 5891 infants developed *** overall incidence of NEC was 3.7%.In 194 infants with NEC, the incidence of PVG was 33%(n = 64).Gestational age (30.8 ±4 vs 29.3 ±4.2 weeks; P =.02) but not birth weight (1609 ±761 vs 1434 ±810 g; P = NS) was greater in infants with PVG compared with infants without PVG (n = 130).Sixty-six (34%) infants with NEC underwent *** intervention occurredmore frequently in infants with PVG compared with infants without PVG (OR, 2.5; CI, 1.37-4.76; P =.003)-only 48%of infants with PVG underwent *** the variables, gestational age, severe NEC (Bell stage III), severe intramural gas (in all 4 abdominal quadrants), and the presence of PVG, severe NEC was most highly associated with OP (OR, 77.47; CI, 10.36-580.16; P < .0001).Bell stage III NEC was present in 98%of infants who underwent OP compared with 40%of infants without OP (P < .0001).Of all infants with NEC, 37 (1
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