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An antenatal high-risk assessment form has facilitated the identification of the fetus at risk, Although such a form in general has potential limitations its simplicity and demonstrated ability to assist in high-risk selection makes it worth including in an antenatal high-risk program.

Argininosuccinate synthetase activity in amniotic fluid cells from a fetus at risk for citrullinaemia was low compared to the activity in amniotic fluid cells from a normal fetus, but five times the activity in fibroblasts from a patient with citrullinaemia. These enzyme values indicated indicated a normal or heterozygous fetus. Chromosome analysis of the amniotic fluid cells from the fetus at risk, however, showed an unusual X/20 translocation. As we could not guarantee the delivery of a normal child, the parents chose to have a therapeutic abortion. Argininosuccinate synthetase activity in the liver and kidney of the aborted fetus was in the normal and heterozygous range respectively, confirming the prenatal diagnosis. The activity in the father's fibroblasts was low, less than 10% of normal. The difficulty of interpreting the results of prenatal diagnosis in such a family and the importance of studying parental cells are discussed.

In the Soroka Medical Center in Beer-Sheba during the two annual periods 1969 and 1979, 693 cesarean sections were performed, of which 633 are presented. The main reasons for the rise in cesarean section rate from 2.6% in 1969 to 8.0% in 1979 were evaluated. Cesarean sections were performed more often for fetal indications during 1979 than in 1969, reflecting the change in our approach to the management of the fetus at risk. The increase in the cesarean section rate was concomitant with a drop in the perinatal mortality from 23/1000 in 1969 to 13.1/1000 in 1979.

The oxytocin challenge test (OCT) has been used to identify and follow the fetus at risk for uteroplacental insufficiency. Of 389 patients who had at least one OCT prior to 38 weeks' gestation, 26 (6.7%) underwent delivery after spontaneous onset of premature labor within 5 days of an OCT. This compares to a 7.5% incidence of spontaneous delivery prior to 38 wk at the University of California Irvine Hospital, and to a 7.6% rate of premature delivery after spontaneous onset of labor in those patients followed with nonstress tests only.

Objectives of perinatal diagnosis include (1) determining if a fetus at risk actually has a disorder, (2) enabling a health care team to evaluate and institute appropriate therapy, and (3) giving parents information that is usually reassuring. The two major areas are the diagnosis of genetic disorders and the assessment of fetal well–being. In the last two decades a variety of techniques have become available, including (1) amniocentesis, (2) amnioscopy, (3) fetoscopy, (4) ultrasonography, (5) radiography including amniography and fetography, (6) measurements of hormones and enzymes in maternal plasma, urine, and amniotic fluid, (7) antepartum biophysical testing, and (8) intrapartum fetal surveillance. The abovementioned techniques are considered separately.

Fetal heart rate profiles for periods up to 12 hours prior to delivery have been reviewed in 515 patients with a fetus at risk. Mechanisms other than fetal asphyxia will cause fetal heart rate decelerations, and fetal asphyxia may in some instances develop in the absence of total or late decelerations. However, an increasing incidence of total decelerations and late decelerations and particularly a marked pattern of total decelerations and late decelerations are of value in the prediction of fetal asphyxia. Fetal heart rate deceleration patterns can predict the probability of fetal asphyxia at the time of initial intervention, while a progression of fetal heart rate deceleration patterns in the individual fetus can be of assistance in the subsequent scheduling of serial acid-base assessments during labor.

Utilization of the nonstress test in the high-risk pregnancy as the sole test for the assessment of fetal welfare is reported. A total of 1,005 tests were performed on 367 patients. A single acceleration in response to fetal movement was deemed sufficient to classify a fetus as reactive, and when present was associated with a corrected perinatal loss of zero. A nonreactive pattern predicted the four stillbirths in the series.

In a family with two children affected by juvenile neuronal ceroid lipofuscinosis (JNCL) an attempt was made at the prenatal diagnosis of the disorder. The following tissues from the fetus at risk were investigated by electron microscopy and were found to be free of fingerprint profiles and curvilinear bodies, typical for JNCL: uncultivated amniotic fluid cells, lymphocytes isolated from fetal blood, and fetal skin biopsy specimens. The child was born at the 34th week of gestation and was clinically normal at the age of 15 months. Postnatally, lymphocytes (isolated at the age of 6 and 15 months) and skin tissue (taken at the age of 15 months) were found to be morphologically normal. It is highly unlikely that the child is affected but definite proof of the absence of JNCL remains difficult at this age.

The effect of a MGL upon fetal activity has been studied in 39 normal and 54 high-risk pregnant patients between 30 and 42 weeks' gestation. The perinatal morbidity and mortality rates were significantly lower in the group showing an increase in fetal activity following a MGL. It is suggested that this may be useful for identifying the fetus at risk.

Numerous proposals for antepartum assessment of fetal well-being have been published in recent years. Undoubtedly the nonstress test (NST) plays a major role as a screening method for detecting the fetus at risk of chronic hypoxia.

One hundred thirty-one postdate pregnancies were evaluated by the sonographic biophysical profile. Results of prenatal testing were compared to neonatal condition. Predictive values were calculated in order to determine whether this testing scheme could be used to detect the fetus at risk for neonatal distress. The results of this study show that a normal biophysical profile score is highly predictive of normal outcome, but an abnormal test has only a 14% predictive value of poor neonatal outcome.

We applied a recently developed and more direct technic to diagnose thalassemia syndromes associated with deletion of particular globin structural genes and to assess a fetus at risk for one of those conditions, deltabeta-thalassemia. The method allows assessment of the globin genes present in total cellular DNA and is applicable to amniotic-fluid cell DNA. Cellular DNA fragments produced by cleavage using two specific restriction endonucleases are separated on the basis of size by agarose-gel electrophoresis, and the distribution of specific sequences among the DNA fragments determined by molecular hybridization. We observed the total deletion of alpha-globin genes in homozygous alpha-thalassemia (hydrops fetalis with hemoglobin Bart's) and the deletion of particular beta and beta-like sequences in cases homozygous for hereditary persistence of fetal hemoglobin and deltabeta-thalassemia. Analysis of amniotic-fluid cell DNA from a fetus at risk for deltabeta-thalassemia demonstrated the feasibility of these improved methods for antenatal diagnosis. The molecular studies confirmed the diagnosis predicted by analysis of fetal blood and established at birth.

This report describes the prenatal ultrasound evaluation of a fetus at risk for the severe X-linked recessive form of myotubular myopathy

Summary. Information concerning 15037 singleton deliveries in 1970 showed that among the 3.5% where the male head of the household was unemployed there was no significant excess of low birthweight or pre-term delivery, once social class had been taken into account. There were major differences, however, in maternal health behaviour. In order to ascertain whether the health behaviour might be a consequence of the unemployment, data were also analysed for the 658 pregnancies in women whose husbands, though employed at delivery, were subsequently unemployed. Almost identical patterns were found, implying that the association with health behaviour was not a time-related consequence of unemployment.

Summary: Amnioscopy has been used in late pregnancy to monitor the amniotic fluid of the fetus at risk of intra-uterine hypoxia. The test has been performed on more than 3,000 patients over a 7-year period. Properly performed it is a worthwhile clinical procedure since it can improve the quality of antenatal care for the fetus who is at risk. Apart from this it has been of assistance in the induction of labour, the early detection of unsuspected abnormalities and research on membrane cytology.

• Although the presence of fetal breathing movements (FBMs) has been suspected for almost a century, the major advances in the field were made during the last decade. Experimental animal techniques of detection include instrumentation of fetuses with electronic recording equipment. Human studies use more indirect, although no less accurate, A-mode or real-time B-scan ultrasonography in the recording of FBMs. The fetus does not make breathing movements continuously; however, there are periods of FBMs interspersed with periods of apnea. Inherent to FBMs is a diurnal variation. Hypoxia and hypoglycemia diminish FBMs, while hypercarbia and hyperglycemia have the opposite effect. Caffeine, barbiturates, and general anesthetics modify FBMs by their influence on the CNS. Preliminary studies have shown the presence of FBMs to indicate a state of fetal wellbeing. Possibly, in the future, testing for FBMs may become a useful clinical tool in the identification of the fetus at risk. (Am J Dis Child1983;137:177-181)