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2023 APR 1 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- Data detailed on Obesity, Fitness and Wellness have been presented. According to [...]

2022 MAY 7 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- A new study on engineering is now available. According to news reporting [...]

2022 MAR 19 (NewsRx) -- By a News Reporter-Staff News Editor at Obesity, Fitness & Wellness Week -- Investigators publish new report on acidosis. According to news originating from New [...]

2021 JUN 24 (NewsRx) -- By a News Reporter-Staff News Editor at Women's Health Weekly -- According to news reporting based on a preprint abstract, our journalists obtained the following [...]

No negative correlation has been found between maternal exercise and fetal heart rate in healthy pregnancies. Although heart rate response was linked with advancing gestational age, brief exercise resulting in a maternal heart rate of 170 beats per minute did not bring about fetal distress. Baseline maternal physical fitness did not significantly affect fetal heart rate response.

The nonstress test has been used to document second and third trimester fetal well-being for the past 40 years. It serves as a surrogate measure of the developing fetal autonomic nervous system. The nonstress test is more specific than sensitive, thus being a better indicator of fetal health than fetal illness. The test itself is read as reactive or nonreactive and may be repeated at intervals as a screen for high-risk maternal conditions. KEY WORDS. Fetal monitoring; heart rate, fetal; fetal distress; pregnancy, high-risk. (J Fam Pract 1996; 43:443-448), During the past 20 years, several testing modalities have been growing in popularity and usefulness in the ongoing effort to improve the safety, predictability, and reliability of obstetrical care. One [...]

Transvaginal Doppler ultrasound appears to detect the fetal heart beat earlier than transabdominal ultrasound. A group of 141 women between six and twelve weeks pregnant had both procedures. Vaginal ultrasound examination detected the fetal heart beat in 61% of cases versus 23% of abdominal ultrasound examinations in week 8 of pregnancy. In week 9, vaginal ultrasound detected the heart beat in 88% of pregnancies versus 56% for abdominal ultrasound. Neither technique could accurately determine that there was no fetal heart beat.

Nonstress tests performed on pregnant women to measure fetal heart rate patterns may not accurately predict fetal heart rates when conducted at intervals more than two days apart. Researchers conducted daily nonstress tests on 100 healthy women 36 weeks pregnant or more. Neural networks using pattern recognition and repetitive exposure to fetal heart rate values were designed to predict fetal heart rates. Trained neural networks could predict variations in fetal heart rate, but not elements of resting fetal heart rate. Neural networks could not be trained when nonstress tests were performed more than two days apart. Fetal heart rate variations were more predictable than fetal heart rate accelerations. Multiple regression formulas and neural networks may not be useful in predicting significant fetal heart rate changes.

A magnetocardiogram appears to be an effective means of monitoring fetal heart rates. The fetal magnetocardiogram is a recording of the electrical activity of the heart generated from magnetic pulses. It is better than an electrocardiogram at screening out the mother's heart signals. Researchers used mapping techniques to evaluate the spatiotemporal properties of fetal magnetocardiograms from 20 pregnant women between 22 and 39 weeks' gestation. The magnetocardiograms showed distinct variations in waveforms depending on where the sensor was placed on the abdomen. The magnetocardiogram proved to be more sensitive to the position of the fetus than an electrocardiogram. Evaluation of magnetocardiograms in conjunction with ultrasound findings may enhance detection of fetal heart abnormalities.

Monitoring fetal heart rate by auscultation does not appear suitable for busy labor and delivery rooms. Auscultation is listening to body sounds, usually with a stethoscope. The American College of Obstetricians and Gynecologists (ACOG) has recommended the use of either electronic heart rate monitoring during labor or auscultation of the fetal heart for 60 or more seconds every 15 minutes in the first stage of labor and every five minutes in the second stage. Of 862 pregnant women in labor, auscultation was begun as the main method of fetal monitoring in 423. Auscultation could not be initiated in 420 because there were not enough nurses available, in 12 because they were obese and in 7 because they refused. Auscultation was stopped before delivery in 392 of the 423 women. In almost all cases, auscultation was stopped because nurses either could not auscultate or record the results as often as the ACOG criteria demanded.

OBJECTIVE: New portable devices have become available for home monitoring of fetal heart rates; these devices have the potential to immediately transmit these tracings to a medical facility. The null hypothesis of this study is the inability of mothers to perform their own nonstress tests (self-nonstress tests) and that such tests are not comparable to those performed by professional medical personnel (assisted nonstress tests). STUDY DESIGN: The feasibility of maternal self-testing was established in 50 high-risk patients followed by a controlled clinical trial conducted in 60 patients. The latter study represents the first controlled trial in which patients performed self-nonstress tests at their homes and transmitted the tracings via telecommunication to our perinatal unit. In all cases these patients came to our hospital within 60 minutes after the self-nonstress tests to have a perinatal nurse perform a second nonstress test. The pairs of self and assisted fetal heart rate tracings were independently reviewed by two investigators. RESULTS: The self and assisted tracing pairs were judged satisfactory for interpretation in 100% and 90%, respectively; self and assisted were interpreted by each examiner to be nonreactive in 20% and 14%, respectively. However, both examiners were unable to distinguish between tracings generated by assisted nonstress and self-nonstress tests. Furthermore, cost analysis revealed an estimated twofold savings with self-nonstress testing compared with the assisted nonstress test. CONCLUSION: Self-nonstress testing is a reliable and accurate method of antepartum fetal heart rate testing. This method of fetal assessment not only introduces a new approach to fetal surveillance with added convenience to patients, but may also significantly reduce medical cost without compromising the results of fetal testing. (Am J Obstet Gynecol 1992;166:489-92.)

OBJECTIVES: Our objectives were to determine the success rate in flow velocity waveforms in the first-trimester fetal circulation and to establish possible preferential flow to the fetal cerebrum at this early stage of gestation. STUDY DESIGN: Flow velocity waveform recordings were made in the umbilical artery, fetal descending aorta, and fetal intracerebral arteries in 30 normal pregnancies between 11 and 13 weeks of gestation. RESULTS: Technically acceptable waveforms were obtained from the descending aorta in 15 fetuses, from the intracerebral circulation in 17 fetuses, and from the umbilical artery in all 30 fetuses. Absent end-diastolic velocities in the descending aorta and umbilical artery were associated with forward flow throughout the cardiac cycle in intracerebral arteries. CONCLUSION: A relatively low cerebral vascular resistance in the late-trimester normal fetus is suggested. (Am J Obstet Gynecol 1992; 166-46-9.)

Pulse oximetry is an inexpensive, noninvasive method of measuring heart rate and arterial oxygen saturation (a comparison between the amount of oxygen in a sample of blood with the amount that could be present); its use has brought dramatic changes in patient monitoring. The method was evaluated for fetal monitoring during labor and delivery. Two studies were carried out: one used pulse oximetry on fetuses during 86 deliveries, and the other used the method before and after the induction of labor in 40 women. In the first study, all fetuses were delivered in good condition, and oximetry values for these uncomplicated deliveries are presented. Average oximetry readings in later stages of labor were lower those than in early labor, indicating a fall in oxygen saturation. In the second study, the membranes surrounding the fetus were ruptured, but prior to this, oximetric recordings were possible through the intact membranes. Oxygen saturation did not appear to change after membrane rupture. Disadvantages of other methods of fetal monitoring (heart rate evaluation, and blood sampling) are cited, and the merits of recording oxygen saturation versus recording partial pressure (the amount of dissolved gas) are discussed. Technical aspects of the oximeter are explained. Although the approach has limitations, particularly those due to fetal presentation (position and movement through the birth canal), it can be applied in obstetrics to help detect fetal complications. (Consumer Summary produced by Reliance Medical Information, Inc.)

If pregnant women are given a nonstress test while sitting up, the test could be done in 10 minutes rather than 20. Nonstress tests are used to analyze the fetal heart rate.

Magnetocardiography may be useful in monitoring fetuses with heart block. A 31-year-old pregnant woman had an ultrasound scan at 20 weeks because her baby's heart rate was slow. The infant's heart was monitored using magnetocardiography at 25, 29, 32, 35, and 37 weeks and she delivered at 38 weeks. At 25 weeks, only the signal from the infant's ventricle was detected but both atrial and ventricular signals could be detected at 29 weeks. The infant was healthy at delivery.

ST. PETERSBURG, FLA. -- Practice will never make perfect when it comes to clinicians reading fetal heart rate tracings, according to Dr. Lawrence Devoe. Even when following the latest guidelines [...]

Cardiotocography could never be described as an exact science, even by the most ardent enthusiast, and for most junior hospital doctors its hidden meaning is seldom revealed. It does, however, [...]

An article by Levi et al. in the July 1990 issue of Radiology examines the use of endosonography (imaging of internal tissues by means of high-frequency sound waves) in studying small embryos. Prior to the advent of endovaginal sonography, the ability to evaluate the development of these small embryos was limited. A number of important issues are raised by new findings. The presence or absence of cardiac pulsations in embryos is an important determinant of a successful pregnancy. The combination of a highly developed embryo as seen by traditional sonography and the lack of cardiac activity has been considered almost 100 percent accurate in predicting a poor outcome of the pregnancy. The ability of endovaginal sonography to image embryos at a much smaller and earlier stage brings into question how detection of cardiac activity in these embryos will relate to outcome. The research of Levi suggests that embryos that will have a favorable prognosis can now be imaged before cardiac activity can be detected. This and other research indicate that in embryos with a crown-to-rump length of less than 4 mm, lack of cardiac activity is normal. The importance of this finding is that being able to visualize an embryo and not detecting cardiac activity is not necessarily indicative of a poor outcome. Another consideration is that since most pregnancies that spontaneously abort do so before traditional sonography could image the embryos, this new technique, which can image embryos much earlier, will reveal more frequent losses of these embryos, even when cardiac activity can be detected. The ability to image embryos at an earlier stage of development will significantly improve early evaluation of pregnancy. (Consumer Summary produced by Reliance Medical Information, Inc.)

Fetal distress accounts for 13.2 percent of all cesarean sections (removal of the fetus by abdominal incision). Traditionally, prior to and during the operation, measurement of the fetal heart rate is discontinued and fetal status remains temporarily unknown. However, in two cases of cesarean section, continuous fetal heart monitoring altered the management of the operation. In one delivery, continuous fetal monitoring revealed a declining heart rate, which impelled the surgeon to deliver the fetus faster. In another case, monitoring the fetal heart rate indicated that the fetus was stable, thus preventing potential complications due to rushed surgery. Continuous fetal heart monitoring is therefore useful in improving fetal and maternal outcomes.