Maternal short-term exposure to NO2 during pregnancy and its relationship with Doppler markers of placental function.

BACKGROUND: Maternal exposure to air pollution has been associated with poor obstetric outcomes. However, the available evidence on the impact of maternal exposure to air pollution on placental function is still scarce and is based on estimated ambient levels of air pollutants. OBJECTIVE: To evaluate the association between short-term maternal exposure to NO2 based on the objective personal measure of NO2 exposure and Doppler markers of placental function. METHODS: This study was based on a prospective cohort of 101 pregnant women, recruited at Hospital Sant Joan de Déu, Barcelona (Spain), between January 2017 and April 2018. NO2 diffusion tubes were worn by pregnant women to measure personal exposure to NO2 between weeks 28 and 32 of their pregnancy. Placental function was evaluated at the 32nd week of gestation by Doppler evaluation of mean uterine arteries pulsatility index (PI), umbilical artery PI, middle cerebral artery PI, cerebroplacental ratio (CPR) and ductus venosus PI. Linear regression models were applied to estimate the association of personal NO2 exposure and Doppler markers of placental function (one at a time), controlled for relevant covariates. RESULTS: Higher personal exposure to NO2 was significantly associated with lower mean uterine artery PI. Each one-interquartile range (IQR) increase in the exposure to NO 2 was associated with -0.07 (95% confidence intervals (CIs): -0.12, -0.02) decrease in uterine arteries PI. We also observed some suggestions for an inverse association between this exposure and CPR. A one-IQR increase in NO2 was associated with -0.18 (95% CIs: -0.37, 0.01) decrease in CPR. The findings for the rest of Doppler markers were not conclusive. CONCLUSIONS: Maternal exposure to NO2 could interfere with Doppler markers of placental function, potentially indicating a certain degree of cerebral vasodilatation with a decrease of mean uterine arteries PI.

Rotura de vasa previa: comunicación de un caso y revisión de la literatura / Rupture of vasa previa: case report and review of the literature

La vasa previa es una situación que se produce cuando vasos fetales intramembranosos aberrantes, procedentes de la placenta o del cordón umbilical, atraviesan el orificio cervical interno y se sitúan por delante de la presentación fetal. Su incidencia es de 1/2.000-1/3.000 embarazos, y la mortalidad perinatal asociada es del 52-66%, aproximadamente. La reducción de esta elevada mortalidad se basa en su diagnóstico prenatal. Exponemos a continuación el caso clínico de una gestante, con controles obstétricos correctos, que acude a urgencias a las 34,5 semanas por rotura prematura de membranas, objetivándose un líquido amniótico hemático y bradicardia fetal severa, por lo que se realiza una cesárea urgente, naciendo una niña con anemia severa, que ingresa en la unidad de neonatología, presentando buena evolución posterior. Presentamos también una revisión de la literatura de los años 1980 al 2008, a través de Medline, usando las palabras «vasa previa» (AU)

Vasa previa is a condition in which the intramembranous fetal blood vessels within the placenta or umbilical cord cross the internal os and become trapped between the fetus and the opening of the birth canal. The incidence of this entity varies from 1/2000 to 1/3000 pregnancies and the associated perinatal mortality rate has been reported to be as high as 52-66%. Reduction of this high perinatal mortality depends on prenatal diagnosis. We report the case of a pregnant woman with no abnormalities in antenatal visits who presented to the emergency service at 34.5 weeks of pregnancy due to premature rupture of membranes, at which time blood-stained amniotic fluid and severe fetal bradycardia were noted. An emergency cesarean section was performed. A female neonate was delivered with severe anemia. The neonate was admitted into the neonatology unit and subsequent outcome was favorable. We also provide a review of the literature published between 1980 and 2008 using Medline, with the key words "vasa previa" (AU)

Hidropesía fetal / Hydrops foetalis

Objetivo: Revisión de casos de hidropesía fetal en nuestro hospital en el período 2000-2008.Material y métodos: Hemos revisado todos los casos de hidropesía fetal diagnosticados en nuestro centro en el período 2000-2008, realizando una revisión exhaustiva de cada caso hasta su resolución. Resultados: El 18% se debieron a cardiopatías. Un25% se asoció a malformaciones fetales síndromes. En otro 18% estaba asociado a una cromosopatía. El 12,5% de los casos fueron de causa inmunológica. En un 25% de los casos revisados no hemos hallado ninguna causa materna ni fetal causante del cuadro de hidropesía. Conclusiones: Es una situación de descompensación fetal grave, en que el diagnóstico etiológico es esencial para determinar los casos susceptibles de terapia fetal, establecer el pronóstico y disminuir el riesgo de recurrencia (AU)

Objectives: Review of the cases of hydrops foetalis followed up in our hospital from 2000-2008.Material and methods: We have reviewed allcases of hydrops foetalis which were diagnosed in our centre from 2000-2008, with an exhaustive review of every case until its resolution. Results: Hydrops foetalis was the result of a heart disease in 18% of cases; 25% were associated to foetal malformations and syndromes; another 18%were associated to aneuploidies, and 12.5% of cases were due to an immunological cause. No foetal or maternal cause was found in 25% of reviewed cases. Conclusions: Hydrops foetalis is a condition caused by severe foetal decompensation, in which an etiologic diagnose is essential to select those cases for foetal therapy, to determine prognosis and to reduce the risk of recurrence. Despite the progresses in therapy, foetal mortality is still very high (AU)