Monitoring High-Risk Infants

Abstract

In the last decade great advances were made in perinatology, which evaluates fetal growth from 26 weeks of gestation to the end of the neonatal period or the fourth week after birth. The new techniques used in perinatology in recent years include amniocentesis. Evaluation of the amniotic fluid by this technique makes it possible to detect changes and to diagnose chromosomal abnormalities including different types of trisomies. This technique may also reveal the presence of abnormal substances such as a-fetoprotein, which often predicts the risk of malformations such as spina bifida and meningoceles. Also, the evaluation of fetomaternal hormones such as estriol in blood or urine may confirm fetal well-being or detect fetal risk. For example, urine estriol levels of 12 mg collected in 24 hr reveal fetal well-being, whereas levels of 4 mg may detect a fetus at risk (Fig. 18; Table 16).