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PubMed1998

Outcome of fetuses with isolated borderline unilateral ventriculomegaly diagnosed at mid-gestation.

OBJECTIVE: To evaluate the outcome of fetuses with isolated borderline, unilateral ventriculomegaly. DESIGN: A retrospective survey was conducted at four perinatal centers in Israel. SUBJECTS AND METHODS: Only fetuses with one ventricular width of > or = 11 mm and the other < 10 mm were included in the study. In all cases, the difference of the ventricular width between the two ventricles was > 2.4 mm (two standard deviations). Fetuses with other malformations, chromosomal abnormalities, or those with evidence of in utero infection, were not included in the study. RESULTS: Unilateral ventriculomegaly was found in 27 subjects (after excluding one case with unilateral ventriculomegaly and Down's syndrome). The mean width of the enlarged ventricle was 11.7 +/- 0.9 mm, while the other normal ventricle was 7.2 +/- 0.9 mm. The mean gestational age at diagnosis of the unilateral ventriculomegaly was 23.6 +/- 2.7 weeks. In one case, pregnancy was terminated, and pathological examination of the fetal brain failed to detect any structural abnormality. Twenty-five patients delivered at term and only one at 34 weeks' gestation. The neurological development in all 25 fetuses was normal, and one fetus had petit mal seizures. CONCLUSION: Fetuses with isolated, borderline unilateral ventriculomegaly, but without other abnormalities, have a good neurological outcome.

Cerebral Ventricles↗
PubMed1999

Nuchal translucency in fetuses affected by homozygous alpha-thalassemia-1 at 12-13 weeks of gestation.

OBJECTIVE: Fetuses affected by homozygous alpha-thalassemia-1 are anemic in the first trimester. We studied their nuchal translucency (NT) measurements at 12-13 weeks of gestation. METHODS: Nuchal translucency was measured prospectively in fetuses at risk of homozygous alpha-thalassemia-1. Measurements of those fetuses subsequently confirmed to be affected by homozygous alpha-thalassemia-1 but with a normal karyotype were compared to those of 440 controls. The controls were from the general obstetric population who had NT measurements at 12 or 13 weeks with known normal outcome. All the NT measurements were expressed as multiples of the median (MoM) for the gestational day. RESULTS: Between 1996 and 1998, 94 at-risk pregnancies were studied. Of these, 32 were subsequently confirmed to be affected by homozygous alpha-thalassemia-1. Chromosome study was not carried out in three cases and these were excluded from the analysis. Nuchal translucency MoMs for cases and controls were found to fit a log Gaussian distribution. The log means (standard deviation) for case and control NT MoM were 0.075 (0.156) and -0.0019 (0.091), respectively. The median NT MoM (95% CI) for cases was 1.19 (1.08-1.62) and was significantly higher than that of the controls (p < 0.001). However, there was extensive overlap of NT between cases and controls. CONCLUSION: Overall, there was a 19% increase in NT MoM in fetuses affected by homozygous alpha-thalassemia-1. This represents a difference of only 0.3-0.4 mm, which is clinically insignificant. This finding indirectly suggests that the increased NT in trisomic fetuses cannot be explained by fetal anemia. Conversely, the presence of increased NT in a fetus at risk of homozygous alpha-thalassemia-1 should alert one to the possibility of chromosomal abnormality rather than being attributed to fetal anemia.

Adolescent↗
PubMed2000

Fetal cerebral blood flow redistribution in late gestation: identification of compromise in small fetuses with normal umbilical artery Doppler.

OBJECTIVE: To evaluate the role of middle cerebral artery Doppler in small fetuses during the late third trimester. DESIGN: Prospective observational study of structurally normal fetuses with an estimated fetal weight < 5th percentile for gestation. Perinatal outcome was determined using a structured datasheet sent to each referring obstetrician. SUBJECTS: Structurally normal fetuses at 35 or more weeks of gestation referred during a 2-year period to the fetal growth clinic of a regional fetal medicine unit in North London. Fetuses with aneuploidy and/or major structural abnormalities were excluded. METHODS: Umbilical artery and middle cerebral artery (MCA) Doppler waveforms were recorded and considered abnormal if above 95th or below 5th percentiles, respectively. Amniotic fluid was considered reduced if the maximum vertical cord-free pool was < 2 cm. The placenta was considered mature if the Grannum grade was II or III. The head circumference (HC)/abdominal circumference (AC) ratio was considered abnormal if > 95th percentile for gestation. Fetal growth, amniotic fluid, biophysical profile score and umbilical artery Doppler were used to advise the referring obstetrician about fetal well-being and he/she independently decided both the timing and mode of delivery. RESULTS: Forty-seven fetuses fulfilled the entry criteria. Thirty-four (72%) demonstrated normal umbilical artery Doppler waveforms. Sixteen (34%) demonstrated middle cerebral artery redistribution, of which nine (56%) had normal umbilical artery Doppler waveforms. MCA blood flow redistribution was associated with an increased incidence of cesarean delivery and need for neonatal admission. Of all gray-scale parameters, an elevated HC/AC ratio has the strongest association with MCA blood flow redistribution (15/16 vs. 1/31; P < 0.01). CONCLUSIONS: MCA Doppler may be a useful tool to assess the health of small fetuses in the late third trimester. Redistribution may occur in the presence of normal umbilical artery Doppler and should be suspected when the HC/AC ratio is elevated.

Adult↗
PubMed2000

The coronary sinus in the fetus.

INTRODUCTION: The normal coronary sinus drains venous blood from the cardiac veins to the right atrium. In some instances, the coronary sinus may be dilated due to volume or more rarely pressure overload. AIMS: To assess the feasibility of detecting the coronary sinus in the fetus and to establish the normal values of the coronary sinus dimensions throughout gestation. SUBJECTS AND METHODS: Fetal echocardiography was performed in 78 normal fetuses from the 16th to the 40th week of gestation (median 25 week). The coronary sinus was measured in four-chamber view (87% of cases) or in parasternal short axis view equivalent (13%). A second group of nine fetuses with a dilated coronary sinus was compared to the normal group. RESULTS: Adequate imaging of coronary sinus was obtained in 97.4% of the normal fetuses. The diameter of the coronary sinus ranged from 1 to 3.2 mm (2 mm +/- 0.13 mm, mean +/- 5% confidence interval) and correlated well with the age of pregnancy (r = 0.86). The length-to-diameter ratio of 24% (+/- 6%) did not vary throughout pregnancy. All nine fetuses with a dilated coronary sinus had a persistent left superior vena cava which drained into it. The diameter of the coronary sinus was approximately three times larger in the abnormal group with a diameter-to-length ratio of approximately 83% (P < 0.0001). CONCLUSION: The coronary sinus is readily identified in the fetus. It gradually increases during pregnancy. An abnormal coronary sinus is easily diagnosed and should prompt the sonographer to look for a persistent left superior vena cava.

Coronary Vessels↗
PubMed2001

Cardiac function in fetuses with intracardiac echogenic foci.

OBJECTIVE: To evaluate cardiac dimensions and function in euploid fetuses with intracardiac echogenic foci. STUDY DESIGN: Forty-eight fetuses with a single cardiac echogenic focus situated in the left ventricle had echocardiography performed at 22-24 weeks of gestation. Fifty normal fetuses at 22-24 weeks' gestation served as controls. Two-dimensional and M-mode directed fetal echocardiography were used to exclude cardiac anomalies and measure right and left ventricular free walls and interventricular septal thickness and ventricular systolic and diastolic dimensions. Cardiac size was expressed as a ratio of ventricular wall thickness/biparietal diameter, and cardiac function was expressed as ventricular shortening fraction. Doppler fetal echocardiography measurements included pulmonary and aortic maximum systolic velocities and time to peak velocities as indices of ventricular systolic function, and the ratio between early ventricular filling (E-wave) and active atrial filling (A-wave) peak velocities at the level of the atrioventricular valves as an index of ventricular diastolic function. RESULTS: Early ventricular filling/active atrial filling peak velocity ratios were significantly lower in fetuses with intracardiac echogenic foci than in control fetuses. In the mitral valve the ratio was 0.37 +/- 0.14 (0.039) (mean +/- SD (95% confidence interval for difference between the means)) vs. 0.59 +/- 0.19 (0.052) and in the tricuspid valve it was 0.42 +/- 0.16 (0.045) vs. 0.62 +/- 0.21 (0.058). No significant differences were found in cardiac dimensions, ventricular shortening fraction and Doppler systolic indices. CONCLUSION: Euploid fetuses with intracardiac echogenic foci show low E/A ratio values in midtrimester echocardiography. This finding might indicate cardiac diastolic dysfunction.

Blood Flow Velocity↗
PubMed2002

Prenatal diagnosis and management of fetuses with liver hemangiomata.

OBJECTIVES: To study the relationship between prenatal appearance and perinatal outcome of fetuses with hepatic hemangiomata with special emphasis on criteria that may help to improve perinatal management. METHODS: In a tertiary referral center six fetuses with hepatic hemangiomata were evaluated by gray-scale, color, and pulsed wave Doppler ultrasound between 1994 and 2000. Fetal blood sampling was performed in four cases. All data (computerized files and video tapes) were analyzed retrospectively. RESULTS: Two fetuses showed very similar sonographic findings. They had an isolated large ('giant') round hepatic hemangioma (diameter 43 and 68 mm, respectively) supplied by one hepatic artery and drained by one hepatic vein, both of them showing high velocity and low pulsatility blood flow. Fetal blood count and coagulation parameters were normal in one case, whereas the other fetus showed a Kasabach-Merritt sequence with severe thrombocytopenia (10 platelets/nL) and mild disseminated intravascular coagulation. Intrauterine platelet transfusion was performed immediately prior to planned Cesarean delivery. Rapid platelet consumption continued postnatally, requiring several thrombocyte transfusions. Platelet counts stabilized only after tumor resection on the second day of life. One fetus with diffuse neonatal hemangiomatosis developed high-output cardiac failure with hydrops in addition to Kasabach-Merritt sequence (15 platelets/nL), and died following premature delivery. Three fetuses, however, showing an isolated small hyperechogenic hepatic hemangioma (5, 5, and 6 mm in diameter, respectively) did not develop any perinatal complications. CONCLUSION: Large fetal liver hemangiomata and diffuse hemangiomatosis may cause severe perinatal complications, particularly high-output cardiac failure and/or Kasabach-Merritt sequence with severe consumption of platelets and clotting factors and hemolytic anemia. Fetal blood sampling enables the prenatal detection of these potential complications, allowing critical modification of perinatal management such as intrauterine platelet transfusion, especially directly before delivery. In contrast, isolated small hyperreflexic hepatic hemangiomata do not appear to be associated with any of these fetal and postnatal sequelae.

Adult↗
PubMed2002

Study of the motor corticospinal system in the developing rat fetus: comparison of Wistar and normal and hydrocephalic HTx rats.

The motor corticospinal system can be identified from day E14 in Wistar and HTx fetuses. There are no significant anatomical differences between the two species of rats. In addition, in day E17 Wistar and HTx fetuses cell counts in the cortical mantle (cortical plate, intermediate zone and germinal matrix) are similar. However, in day E20 fetuses there are significant differences in the number of cells in the cortical mantle of the hydrocephalic HTx fetuses compared to that in the Wistar and normal HTx fetuses, their total number of cells being reduced compared to that of the normal HTx and Wistars. Breakdown of the numbers of cells in the different layers shows that in the hydrocephalics there is a significant reduction in the number of cells in the germinal matrix and intermediate zone but, although the number of cells is also reduced in the cortical plate, the reduction is not significant. Measurements of the anterior/posterior width of the pyramid show that its growth is almost complete by day E17 and that on day E20 the measurements are similar in Wistar and normal and hydrocephalic HTx fetuses. These findings suggest that it is only cells generated after day E17 that are missing from the cortex of day E20 hydrocephalic rats. It is known that the motor corticospinal tract axons arise from pyramidal cells in layers 6, 5 and 4 of the cortical plate. These layers are generated earlier than layers 3 and 2 and are almost certainly in place by day E17 and account for why motor corticospinal tract function is spared in younger animals with established hydrocephalus.

Animals↗
PubMed1995

Relationship between the fetal heart rate pattern and perinatal mortality in fetuses with absent end-diastolic velocities of the umbilical artery: a case-controlled study.

Fetal decompensation is usually diagnosed by the onset of late decelerations and decreased fetal heart rate (FHR) variability and is associated with fetal hypoxemia and acidemia and has a high perinatal mortality. Objective analysis of the FHR pattern can be performed using the Fischer score and a score of less than 6 correlates with fetal decompensation. Fetuses with absent end-diastolic velocities (AEDV) of the umbilical artery have severe placental disease and coupled with this a high perinatal mortality and morbidity. Importantly, AEDV is usually observed before the occurrence of fetal decompensation. In fetuses with AEDV, delivery before decompensation may improve the perinatal mortality and morbidity. To test this hypothesis, the perinatal outcome of fetuses with AEDV delivered before decompensation (Fischer score of 6 or more), were compared with similar fetuses delivered after decompensation (Fischer score of less than 6). All FHR pattern records of fetuses who had AEDV with a birthweight greater than 750 g and a gestational age of 28 weeks or more were evaluated using Fischer's score by a single observer unaware of the perinatal outcome. Fifty-seven fetuses qualified for the study and 17 of these babies subsequently died. The babies who died had significantly lower mean Fischer scores during the preceding 6 hours before delivery (5.9 +/- 1.8 SD) than the survivors (7.7 1.9; p < 0.05), but also had lower birthweights and gestational ages.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Fetal liver length measurement does not provide a superior means for prediction of a small for gestational age fetus.

To assess the growth of the fetal liver in normal pregnancies and evaluate the ability of fetal liver length measurement for prediction of small for gestational age fetuses, ultrasonographic examinations were performed on 162 normal fetuses, ranging from 15 to 40 weeks menstrual age. The optimal mathematical function and normal range of liver length were generated. The liver length was obtained in 21 small for gestational age fetuses between 34 and 40 weeks, and the ability to use fetal liver length measurement for prediction of small for gestational age fetuses was investigated. A curvilinear relationship was found between the menstrual age and liver length (R2 = 91.9%), and a normal range of liver length measurement for estimating the growth of the fetal liver during normal pregnancy was generated. The liver length was normal in 19 of 21 small for gestational age fetuses (90.5%). The fetal liver length measurement does not provide a superior means for identifying the small for gestational age fetus.

Embryonic and Fetal Development↗
PubMed1994

Motor and cardiac response during habituation testing: demonstration of exaggerated cardiac reactivity in a subgroup of normal human fetuses.

In this study we wanted to determine: (1) whether or not a relationship existed between the rate of habituation of the fetal motor response and changes in the fetal heart rate (FHR), and (2) if this relationship could be used to identify a subgroup of fetuses who exhibited exaggerated cardiac reactivity during habituation testing. Thirty-nine normal human fetuses between 34 and 40 weeks of gestation were evaluated. Habituation testing consisted of a 1 second vibroacoustic stimulus with a 10 second interstimulus interval for eight trials. The motor response was observed using real-time sonography, and a score of 0 to 10 was assigned for each trial based on subjective assessment of the fetal response. Motor habituation was evaluated in terms of the rate of response decrement in movement over trials (Re). Subjects were initially divided into slow and fast motor habituators based on the median of Re, and it was found that fetuses whose motor response habituated slowly displayed a significantly greater increase in heart rate compared with fetuses who habituated more rapidly (F1,37 = 8.61; P = 0.0057). Cardiac reactivity was then defined as "the average increase in FHR above the mean prestimulus value during the last half of the testing period." When the data were divided into quadrants based on medians, we identified seven (18%) fetuses who habituated rapidly but who also displayed high cardiac reactivity. We conclude that there is a significant relationship between the magnitude of the increase in FHR above baseline and the rate of motor habituation in normal human fetuses.

Acoustic Stimulation↗
PubMed1998

Pre-natal brain development of fetuses with a myelomeningocele.

Biometric measurements of 21 fetuses referred to the Fetal Management Unit at St. Mary's in Manchester with a diagnosis of myelomeningocele were analysed. Five fetuses had more than 3 sets of measurements carried out, the last of which were performed during the 3rd trimester. The majority of the head circumference measurements were on or below the 3rd percentile for normal head size whilst almost all of the cerebral ventricular atrial measurements were more than 10 mm, a figure generally accepted as being at the upper limit of normal, measurements above this indicate that ventriculomegaly is present. In normal fetuses the atrial measurement is constant at or below 10 mm throughout gestation, but in the fetuses with a myelomeningocele the atrial measurements got progressively larger as gestation proceeded. Because their head circumferences did not increase disproportionately quickly, there was no evidence that the fetuses were developing hydrocephalus in utero, rather the large atrial measurements were indicative of poor development of the cerebral hemispheres. These findings together with the Arnold-Chiari malformation and the abnormalities in the spinal cord indicate that the central nervous system in its entirety is abnormally developed in fetuses with a myelomeningocele.

Brain↗
PubMed2001

Early and persistent reduction in umbilical vein blood flow in the growth-restricted fetus: a longitudinal study.

OBJECTIVE: We have previously shown, in a cross-sectional study, that the reduction in umbilical vein blood flow in intrauterine growth-restricted fetuses is due to reduced umbilical vein velocity. The purpose of this longitudinal study in intrauterine growth-restricted fetuses was to determine whether the umbilical vein velocity reduction, which, in turn, reduces blood flow, persists throughout gestation or represents a late event that precedes indicated delivery. STUDY DESIGN: Twenty-one intrauterine growth-restricted fetuses with an abnormal umbilical artery velocimetry underwent serial sonographic and Doppler examinations from 23 to 36 weeks of gestation. Umbilical vein diameter and velocity were measured, and umbilical vein absolute (milliliters per minute) and weight-specific blood flow (milliliters per minute per kilogram) were calculated. Umbilical vein diameter, velocity, and blood flow were expressed per abdominal circumference. Intrauterine growth-restricted findings were compared to local reference data. RESULTS: Intrauterine growth-restricted fetuses showed persistent reductions in umbilical vein blood flow per abdominal circumference and weight-specific blood flow (milliliters per minute per kilogram) from the time of diagnosis of intrauterine growth-restriction. Umbilical vein velocity was reduced in the intrauterine growth-restricted fetuses, although umbilical vein diameter did not change. CONCLUSION: Reduction of umbilical vein blood flow is an early finding in intrauterine growth-restricted fetuses, and it can persist for several weeks until delivery. This reduction in blood flow is due to reduced umbilical vein velocity.

Adult↗
PubMed2001

Prevalence of 22q11 deletion in fetuses with conotruncal cardiac defects: a 6-year prospective study.

OBJECTIVES: Conotruncal malformations (CTMs) are a major feature of 22q11 microdeletion (22qdel). The prevalence of 22qdel in fetuses harboring these defects is unknown. We assessed the prevalence of 22qdel in a population of fetuses with conotruncal cardiac defects. STUDY DESIGN: Consecutive fetuses (n = 261) with a CTM and a normal karyotype were included in the study. All fetuses were screened for 22qdel by means of fluorescent in situ hybridization. RESULTS: A 22qdel was found in 54 fetuses (20.7%). The proportion of 22qdel for each CTM was: tetralogy of Fallot (14/100), pulmonary atresia with ventricular septal defect (11/61), tetralogy of Fallot with absent pulmonary valves (6/16), interrupted aortic arch (10/22), truncus arteriosus (9/29), and complex transpositions of the great arteries (4/33). Additional vascular anomalies were present in 75%. Typical abnormal facial appearance at birth or at autopsy was observed in 80%, and thymus hypoplasia, in 76%. The pregnancy was terminated in 41 of 54 cases, including an intrauterine death in one case. The 22qdel was inherited in 7.7%. CONCLUSION: Prevalence of the 22qdel is high in fetuses with CTMs. The risk of mental retardation associated with the respective risk of cardiac surgery for each type of CTM may strongly influence prenatal counseling.

Abortion, Therapeutic↗
PubMed1991

The incorporation of plutonium by the embryo and fetus of rats and guinea-pigs.

The transfer of 238Pu from the maternal circulation to the developing embryo and fetus was studied in rats and guinea-pigs to provide data for the development of dosimetric models for the human embryo and fetus. Following administration at different stages of gestation, measurements were made after 3 days in the rat and 7 days in guinea-pigs. The amount transferred was greater after administration at later stages of gestation, up to a maximum of about 0.8-0.9% of the injected activity per fetoplacental unit (FPU) and about 0.2% per fetus in both species. In advanced gestation the yolk sac, the initial site of haemopoietic stem cells, contained up to 80% of the total activity in the FPU in rats, compared with about 25% for the guinea-pig; retention in placental trophoblast was greater in the guinea-pig. The concentrations of 238Pu in the yolk sac were generally about two to three orders of magnitude greater than fetal concentrations and of the same order as in maternal liver and bone. In both species, concentrations in the embryo and fetus were greatest after injection early in gestation, reached their lowest around mid-organogenesis and increased again in later gestation. The fetus:mother whole-body concentration ratios in late gestation were about 0.1 and 0.05 in rats and guinea-pigs, respectively. Measurements were also made of the 238Pu retention in neonates at birth. In guinea-pigs the liver accounted for about 6-9% of retained activity; similar values for femora indicated skeletal retention of about 60-80%. For administration at each stage of gestation, and particularly at early stages, transfer of 238Pu to the fetus continued throughout gestation but concentrations decreased due to fetal growth.

Animals↗
PubMed1996

In utero transplantation of fetal liver stem cells into human fetuses.

Based on our experience in the field of fetal liver transplantation (FLT) that we have developed since 1976, we initiated, in 1988, in utero FLT into human fetuses, taking advantage of the immunologic tolerance in young fetuses. The transplants have involved fetuses suffering from various diseases at 12-28 weeks postfertilization, with 2 of the 6 cases eventually resulting in abortion. With the 4 other fetuses, a favorable outcome was observed. Three children are more than 4 years old, and they are alive and well, with evidence of engraftment, reconstitution of immunity, and partial correction of beta-thalassemia. In the fourth case, the fetus is alive and well and birth is expected soon. In utero transplantation of stem cells is a therapy with remarkable advantages: (a) tolerance induction due to immune immaturity of the host, (b) lack of graft-versus-host disease (GVHD) due to immaturity of the donor, (c) ideal isolation of the fetus in the maternal uterus, and (d) optimal environment for donor fetal cell development in the vicinity of host fetal cells and growth factors.

Abortion, Spontaneous↗
PubMed1999

Delivery of a severely anaemic fetus after partial molar pregnancy: clinical and ultrasonographic findings.

The incidence of a normal live fetus and a partial molar placenta is extremely rare. Although triploidy is the most frequent association, a fetus with normal karyotype can survive in cases of partial molar pregnancy. We report a case of partial molar placenta in which a live female baby was delivered at 32 weeks gestation by a 30-year-old woman. At the 18th week, ultrasonographic examination revealed a normal fetus with a huge, multicystic placenta. Chromosomal evaluation by amniocentesis revealed a normal female karyotype (46,XX), and serial biometric measurement of the fetus showed normal growth during pregnancy. There were no obstetric complications until the 32nd gestational week when preterm rupture of the membranes occurred. The electronic fetal heart beat tracing showed a repeated sinusoid pattern and late deceleration after admission. The patient underwent emergency Caesarean section and delivered a 1551-g, anaemic female baby with an Apgar score of 1, 4 and 6 at 1, 5 and 10 min, respectively. The baby recovered within 2 weeks after respiratory support and transfusion of packed red blood cells. Although anaemia is one of the risk factors that jeopardize the fetus in the case of partial molar pregnancy, termination is not indicated when the fetus is normal and no complications have occurred.

Adult↗
PubMed2003

An ethical approach to giving couples information about their fetus.

The amount of information available to couples about the health of their fetus is increasing. An important question in prenatal diagnosis is what information should be given to couples, and how best to present it. It has been argued elsewhere that, in the absence of economic constraints on testing, there is no place for limiting the information available to couples about their fetus. However, not every couple wants all available information, and it is not always clear what couples do want to know. Providing unwanted information about the health of a fetus may be harmful in a number of ways. Herein, the potential harms of being given unwanted information about one's fetus are illustrated by using case studies drawn from clinical practice, and a new approach to prenatal diagnosis is suggested. If the harms of being given unwanted information about one's fetus are to be avoided, then couples need an opportunity to limit the data gathered about their fetus at prenatal diagnosis.

Chromosome Aberrations↗
PubMed1988

Reliability of intrapartum fetal heart rate monitoring in the postterm fetus with meconium passage.

Fifty-six postterm fetuses with intrapartum meconium passage underwent routine scalp stimulation and scalp blood sampling. Fetal heart rate (FHR) patterns were compared with blood pH. Nine fetuses (16%) had a scalp pH less than 7.20. Twenty-nine fetuses (54%) demonstrated spontaneous or induced FHR accelerations; none were acidemic. Acidemia with normal variability was found only in conjunction with severe variable decelerations, and may represent respiratory acidosis. In this group, two of nine acidemic fetuses demonstrated no decelerations (pH 7.04) or mild variable decelerations only (pH 7.19). The absence of late decelerations was not as reliable as the presence of accelerations in the prediction of fetal well-being. Thirty-three percent of the fetuses who failed to exhibit spontaneous or provoked FHR accelerations were acidemic. These findings suggest that in this high-risk group of fetuses, the absence of spontaneous FHR accelerations should be followed by an attempt to induce accelerations, scalp pH assessment, or cesarean section.

Acidosis↗