Fetal therapy最新文献

The original description of intraperitoneal transfusion calls for contrast-dye infusion and X-ray confirmation of placement of the needle free in the peritoneal cavity. Ultrasound methods, using air or saline as contrast media, have been described to replace the X-rays. This report illustrates at least one way in which the ultrasound findings at intraperitoneal transfusion may be illusory, allowing misplaced transfusion into the fetal colon. In specific instances, use of radiopaque dye at intraperitoneal transfusion may still be helpful.

Erythrocyte aggregation was studied in 60 samples of cord blood taken at delivery from neonates whose mothers suffered from hypertension or diabetes in pregnancy or from neonates who showed hypoxia during labor. Erythrocyte aggregation significantly increased in the cord blood of neonates who suffered from hypoxia during labor, and in neonates from hypertensive and diabetic mothers. The effects of maternal disease or intrapartum hypoxia may therefore stimulate fetal erythropoiesis and cause major changes in cord blood rheology.

The most common autoimmune hemolytic disorder encountered during pregnancy is idiopathic thrombocytopenic purpura. Premature separation of the placenta is one of the most serious complications in the second half of pregnancy. Since the association of the two is not known, the aim of the present paper is to present such a case and to draw the attention of the obstetrician to this possibility.

A reference range for fetal mean red cell volume (MCV) with gestation was established from the study of samples obtained by cordocentesis from 466 pregnancies undergoing prenatal diagnosis for non-erythrocyte abnormalities. The mean MCV decreased from 145 fl at 16 weeks to 113 fl at 36 weeks of gestation. Alterations in MCV were investigated in 154 red cell isoimmunized and 231 small for gestational age (SGA) fetuses. In red cell isoimmunization, significant macrocytosis was observed when the fetal hemoglobin concentration deficit was greater than or equal to 6 g/dl. In the chromosomally normal SGA fetuses (n = 178), the MCV was increased and the magnitude of macrocytosis was significantly associated with gestation and the degrees of fetal 'smallness' and fetal hypoxemia. However, the most severely macrocytotic SGA fetuses were those with triploidy (n = 22). In the SGA fetuses with other chromosomal defects (n = 31), the MCV was higher than the controls but lower than that of the chromosomally normal hypoxemic fetuses. It is suggested that in severe growth retardation there is developmental delay in the normal evolution from hepatic to medullary hemopoiesis and this is most marked in triploid fetuses. In contrast, in red cell isoimmunization the switch to medullary erythropoiesis is normal, but in severe anemia there is secondary recruitment of hepatic erythropoiesis.

While transplantation of fetal tissues may alleviate a great deal of suffering, current policy bars federal funding of research using tissue from elective abortions. Using fetal tissue from spontaneous abortions would obviate the moral concerns. If existing studies of small samples are extrapolated to the US population, then each year about 750,000 fetuses are aborted spontaneously by week 28 (500,000 in the first trimester and 250,000 in the second trimester). The consensus among researchers is that spontaneously aborted fetuses are few in number, and inappropriate for transplantation because they are born dead or have defects. This intuition may not be supported by the evidence, and there is a compelling need to focus research on these issues.

This retrospective review identified all cases of isolated ventriculomegaly (without spina bifida), encephalocele and microcephaly in approximately 22,000 consecutive patients through the Ultrasound Department at the University of British Columbia, Grace Hospital. 17 cases of isolated ventriculomegaly, 16 cases of microcephaly and 6 cases of encephalocele were identified. Isolated ventriculomegaly and encephalocele were accurately diagnosed prenatally while microcephaly was not consistently identified prenatally. Patients with isolated ventriculomegaly had a positive family history for cranial abnormalities in 24%. The prognosis is difficult to predict for fetuses with ventriculomegaly, but severe ventriculomegaly generally produced a poor outcome while mild or moderate ventriculomegaly resulted in normal development or marginal developmental delay. Chromosome analysis is recommended in all patients with central nervous system lesions and viral studies are recommended with ventriculomegaly and microcephaly.

Pathogenesis and intrauterine treatment of central nervous system defects are described. Current and future developments in fetal therapies and/or surgical correction of malformations and stem cell engraftments are discussed.