Admission cardiotocography: a randomised controlled trial. Cardiotocography only versus cardiotocography plus PR-interval analysis in intrapartum surveillance: a randomised, multicentre trial. FECG Study Group. Randomised controlled trial of cardiotocography versus Doppler auscultation of fetal heart at admission in labour in low risk obstetric population. Cardiotocography only versus cardiotocography plus ST analysis of fetal electrocardiogram for intrapartum fetal monitoring: a Swedish randomised controlled trial. A comparison of intrapartum automated fetal electrocardiography and conventional cardiotocography--a randomised controlled study. Non-stress antenatal cardiotocography--a prospective randomized clinical trial. Cardiotocography plus ST analysis of fetal electrocardiogram compared with cardiotocography only for intrapartum monitoring: a randomized controlled trial. Randomised controlled trial of cardiotocography versus umbilical artery Doppler in the management of small for gestational age fetuses. The Dublin randomized controlled trial of intrapartum fetal heart rate monitoring. Influence of volume preloading on uteroplacental and fetal circulation during spinal anaesthesia for caesarean section in uncomplicated singleton pregnancies. Intermittent versus continuous electronic monitoring in labour: a randomised study. Reducing stillbirths: screening and monitoring during pregnancy and labour.
Admission cardiotocography is widely used to identify pregnancies that might benefit from continuous electronic fetal monitoring in labour. We aimed to compare the effect on neonatal outcome of admission cardiotocography versus intermittent auscultation of the fetal heart rate.
                8580 women admitted to the delivery ward of a Dublin teaching hospital who were at low risk of fetal distress in labour were randomly assigned admission cardiotocography (20 min) or the unit's usual care (intermittent auscultation only, with continuous cardiotocography only if clinically indicated). The primary outcome was moderate to severe neonatal morbidity, or perinatal mortality in the absence of a major congenital malformation. Analyses were by intention to treat.
                44 (1.0%) women assigned admission cardiotocography did not undergo the procedure; 15 (0.4%) assigned usual care had admission cardiotocography. The primary endpoint occurred in 56 (1.3%) of 4298 women assigned admission cardiotocography and 55 (1.3%) of 4282 in the usual-care group (relative risk 1.01; 95% CI 0.70-1.47). Other indices of neonatal morbidity also showed no differences. Despite an increase in use of continuous cardiotocography (1.39; 1.33-1.45) and fetal blood sampling (1.30; 1.14-1.47) with admission cardiotocography, there were no significant differences in the rates of caesarean delivery (1.13; 0.92-1.40), instrumental delivery (1.03; 0.92-1.16), or episiotomy (1.06; 0.99-1.13).
                Routine use of cardiotocography for 20 min on admission to the delivery ward does not improve neonatal outcome. No significant increase in operative delivery was apparent, probably because of liberal use of fetal blood sampling. There is a need to improve the sensitivity and specificity of fetal monitoring during labour. We compared the gold standard, cardiotocography, with cardiotocography plus time-interval analysis of the fetal electrocardiogram in fetal surveillance. The aim was to find out whether time-interval analysis decreased the need for operative intervention due to fetal distress.
                We did a randomised, prospective trial in five hospitals in the UK, Hong Kong, the Netherlands, and Singapore. 1038 women undergoing high-risk labours were randomly assigned fetal monitoring by cardiotocography alone, or cardiotocography plus fetal electrocardiography (ECG). Outcomes measured were rates of operative intervention, and neonatal outcome. Analysis was by intention to treat.
                515 women were assigned management by cardiotocography, and 523 cardiotocography plus fetal ECG. There was a trend towards fewer operative interventions for presumed fetal distress in the time-interval analysis plus cardiotocography group (63 [13%] vs 78 [16%]), but this was not significant (relative risk 0.80 [95% CI 0.59-1.08], p=0.17). There was no significant difference between groups in the proportion of babies who had an umbilical arterial pH of 7.15 or less (51 [11%] vs 49 [11%]; 1.01 [0.7-1.47]), or in the frequency of unsuspected acidaemia (42 [9%] vs 35 [8%]; 1.17 [0.76-1.79]).
                The addition of time-interval analysis of the fetal electrocardiogram during labour did not show a significant benefit in decreasing operative intervention. There was no significant difference in neonatal outcome. To compare the effect of admission cardiotocography and Doppler auscultation of the fetal heart on neonatal outcome and levels of obstetric intervention in a low risk obstetric population.
                Randomised controlled trial.
                Obstetric unit of teaching hospital
                Pregnant women who had no obstetric complications that warranted continuous monitoring of fetal heart rate in labour.
                Women were randomised to receive either cardiotocography or Doppler auscultation of the fetal heart when they were admitted in spontaneous uncomplicated labour.
                The primary outcome measure was umbilical arterial metabolic acidosis. Secondary outcome measures included other measures of condition at birth and obstetric intervention.
                There were no significant differences in the incidence of metabolic acidosis or any other measure of neonatal outcome among women who remained at low risk when they were admitted in labour. However, compared with women who received Doppler auscultation, women who had admission cardiotocography were significantly more likely to have continuous fetal heart rate monitoring in labour (odds ratio 1.49, 95% confidence interval 1.26 to 1.76), augmentation of labour (1.26, 1.02 to 1.56), epidural analgesia (1.33, 1.10 to 1.61), and operative delivery (1.36, 1.12 to 1.65).
                Compared with Doppler auscultation of the fetal heart, admission cardiotocography does not benefit neonatal outcome in low risk women. Its use results in increased obstetric intervention, including operative delivery. Previous studies indicate that analysis of the ST waveform of the fetal electrocardiogram provides information on the fetal response to hypoxia. We did a multicentre randomised controlled trial to test the hypothesis that intrapartum monitoring with cardiotocography combined with automatic ST-waveform analysis results in an improved perinatal outcome compared with cardiotocography alone.
                At three Swedish labour wards, 4966 women with term fetuses in the cephalic presentation entered the trial during labour after a clinical decision had been made to apply a fetal scalp electrode for internal cardiotocography. They were randomly assigned monitoring with cardiotocography plus ST analysis (CTG+ST group) or cardiotocography only (CTG group). The main outcome measure was rate of umbilical-artery metabolic acidosis (pH <7.05 and base deficit >12 mmol/L). Secondary outcomes included operative delivery for fetal distress. Results were first analysed according to intention to treat, and secondly after exclusion of cases with severe malformations or with inadequate monitoring.
                The CTG+ST group showed significantly lower rates of umbilical-artery metabolic acidosis than the cardiotocography group (15 of 2159 [0.7%] vs 31 of 2079 [2%], relative risk 0.47 [95% CI 0.25-0.86], p=0.02) and of operative delivery for fetal distress (193 of 2519 [8%] vs 227 of 2447 [9%], 0.83 [0.69-0.99], p=0.047) when all cases were included according to intention to treat. The differences were more pronounced after exclusion of 291 in the CTG+ST group and 283 in the CTG group with malformations or inadequate recording.
                Intrapartum monitoring with cardiotocography combined with automatic ST-waveform analysis increases the ability of obstetricians to identify fetal hypoxia and to intervene more appropriately, resulting in an improved perinatal outcome. To examine whether intrapartum monitoring by means of automatic ST analysis (STAN) of fetal electrocardiography could reduce the rate of neonatal acidemia and the rate of operative intervention during labour, compared with monitoring by means of cardiotocography (CTG).
                Randomised controlled trial.
                Labour ward in tertiary-level university hospital.
                A total of 1483 women in active labour with singleton term fetus in cephalic presentation.
                Women were randomly assigned to be monitored either by STAN or by CTG. Fetal blood sampling (FBS) was optional in both groups.
                Neonatal acidemia (umbilical artery pH <7.10), neonatal metabolic acidosis (umbilical artery pH <7.05 and base excess <-12 mmol/l) and operative interventions: caesarean section rate, vacuum outlet (VO) rate and FBS rate.
                There were no statistically significant differences between the STAN group and CTG group in the incidence of neonatal acidemia (5.8 versus 4.7%) or metabolic acidosis (1.7 versus 0.7%). The caesarean section rate (6.4 versus 4.7%) and the VO rate (9.5 versus 10.7%) were also similar in the STAN and CTG groups. The incidence of FBS was lower (P < 0.001) in the STAN group (7.0%) than in the CTG group (15.6%).
                Intrapartum fetal monitoring by means of automatic STAN did not improve the neonatal outcome or decrease the caesarean section rate. However, the need for FBS during labour was lower in the STAN group. A randomized controlled trial examined the effects of non-stress antepartum cardiotocography on obstetric management and assessed its usefulness as a diagnostic test of fetal compromise. Daily cardiotocograph recordings were made in 396 antenatal patients at increased risk of fetal compromise but were withheld from the clinicians responsible for care in half the cases. The frequency of intrapartum fetal distress and low Apgar score was similar in the two groups. The three normally-formed perinatal deaths all occurred in the revealed group but in only one case could earlier obstetric intervention have altered the outcome. Availability of non-stress cardiotocography was not associated with an increased rate of induction of labour or caesarean section. To estimate the effectiveness of intrapartum fetal monitoring by cardiotocography plus ST analysis using a strict protocol for performance of fetal blood sampling.
                We performed a multicenter randomized trial among laboring women with a high-risk singleton pregnancy in cephalic presentation beyond 36 weeks of gestation. Participants were assigned to monitoring by cardiotocography with ST analysis (index) or cardiotocography only (control). Primary outcome was metabolic acidosis, defined as an umbilical cord artery pH below 7.05 combined with a base deficit calculated in the extracellular fluid compartment above 12 mmol/L. Secondary outcomes were metabolic acidosis in blood, operative deliveries, Apgar scores, neonatal admissions, and hypoxic-ischemic encephalopathy.
                We randomly assigned 5,681 women to the two groups (2,832 index, 2,849 control). The fetal blood sampling rate was 10.6% in the index compared with 20.4% in the control group (relative risk 0.52; 95% [CI] 0.46-0.59). The primary outcome occurred 0.7% in the index compared with 1.1% in the control group (relative risk 0.70; 95% CI 0.38-1.28; number needed to treat 252). Using metabolic acidosis calculated in blood, these rates were 1.6% and 2.6%, respectively (relative risk 0.63; 95% CI 0.42-0.94; number needed to treat 100). The number of operative deliveries, low Apgar scores, neonatal admissions, and newborns with hypoxic-ischemic encephalopathy was comparable in both groups.
                Intrapartum monitoring by cardiotocography combined with ST analysis does not significantly reduce the incidence of metabolic acidosis calculated in the extracellular fluid compartment. It does reduce the incidence of metabolic acidosis calculated in blood and the need for fetal blood sampling without affecting the Apgar score, neonatal admissions, hypoxic-ischemic encephalopathy, or operative deliveries.
                I. To compare the impact on use of resources in the management of small for gestational age babies using Doppler ultrasound versus cardiotocography.
                A randomised controlled trial.
                A large district general hospital delivering 5500 to 6000 infants each year, 30% to 35% of which are to women of Pakistani origin.
                One hundred and fifty women delivered of small for gestational age infants.
                Primary outcome measures were length of hospital inpatient stay and induction of labour rates. Secondary outcome measures included caesarean section rates and length of stay on neonatal unit.
                The use of Doppler reduced average hospital inpatient stay from 2.5 days to 1.1 days, compared with cardiotocography (P = 0.036). There was no effect on induction of labour rates or caesarean section rates. There was no significant difference in length of stay on the neonatal unit (P = 0.33). There was a reduction in monitoring frequency and fewer hospital antenatal clinic visits.
                The use of Doppler ultrasound to manage small for gestational age infants reduces the use of resources, compared with cardiotocography. In a randomized controlled trial involving 12,964 women, a policy of continuous electronic intrapartum fetal heart monitoring was compared with an alternative policy of intermittent auscultation, both policies including an option to measure fetal scalp blood pH. Women allocated to electronic fetal heart monitoring had shorter labors and received less analgesia. The caesarean delivery rates were 2.4% for electronic fetal heart monitoring and 2.2% for intermittent auscultation but this small difference arose from the identification of nearly twice as many fetuses with low scalp pH (less than 7.20) in the electronic fetal heart monitoring group. The forceps delivery rate was 8.2% in the electronic fetal heart monitoring group compared with 6.3% in the intermittent auscultation group, and this excess was explained by more instrumental deliveries prompted by fetal heart rate abnormalities. There were 14 stillbirths and neonatal deaths in each group, with a similar distribution of causes. There were no apparent differences in the rates of low Apgar scores, need for resuscitation, or transfer to the special care nursery. Cases of neonatal seizures and persistent abnormal neurological signs followed by survival were twice as frequent in the intermittent auscultation group, and this differential effect was related to duration of labor. Follow-up at 1 year of babies who survived neonatal seizures revealed three clearly abnormal infants in each group. The implications of these findings for both theory and practice are discussed. Effects of volume preloading during spinal anaesthesia for elective caesarean section on maternal blood pressure, feto-maternal circulation and fetal outcome.
                In a pilot study a randomised trial was performed in 22 healthy women with uncomplicated, singleton pregnancies at 36-40 weeks of gestation undergoing elective caesarean section under spinal anaesthesia. In the low volume group (group A) patients received 150 ml of crystalloid solution for preloading, in the high volume group (group B) they were given 15 ml/kg of crystalloid solution for preloading before the initiation of spinal anaesthesia. Maternal blood pressure was monitored intermittently. Hypotension was defined as a decrease in systolic pressure to less than 80% of the baseline value. The Doppler flow evaluation consisted of measurements from the uterine artery at the placental site, fetal umbilical artery and fetal middle cerebral artery. Pulsatility indices were derived before and after fluid preloading, and when spinal anaesthesia was established. The neonatal outcome was assessed by Apgar scores, arterial acid base status and neurologic and adaptive capacity scores (NACS).
                The incidence of maternal hypotension in both groups was 45.5% (n = 10); 3 cases occurred in group A compared to 7 cases in group B (n.s.). There was no evidence that the high dose volume is useful in preventing maternal hypotension. The pulsatility indices of uterine arteries, umbilical arteries and middle cerebral arteries were not altered. Statistical analysis showed no changes in neonatal outcome concerning umbilical arterial pH, Apgar score and NACS (n.s.) between groups A and B.
                Our preliminary results suggest that high dose crystalloid volume preloading has no preventive function in the avoidance of maternal hypotension in healthy parturients undergoing elective caesarean section under spinal anaesthesia, and shows no harmful effects on neonatal outcome as long as maternal hypotension is corrected immediately. However, the statistical significance may reflect the small sample size, and larger series are needed before changing the current management.
                Copyright 2002 S. Karger AG, Basel To compare the efficacy in detecting signs of fetal hypoxia in labour of intermittent (I-group) versus continuous (C-group) electronic fetal monitoring in women with low or moderate risk factors for fetal distress.
                A prospective, randomised study.
                A tertiary referral centre.
                Four thousand and forty-four parturients at low risk for obstetric complications with a reactive fetal heart rate admission test at arrival in labour. During the study period (October 5 1989 to May 31 1991), 5647 women were delivered in the labour ward. Of these, 1178 women (20.9%) were excluded because of high risk factors in pregnancy or at admission for labour, including women undergoing elective caesarean section. Of the remaining 4469 women 4044 (90.5%) were randomised to either intermittent (n = 2015) or continuous monitoring (n = 2029) during the first stage of labour.
                In the C-group the fetal heart rate was recorded continuously with electronic fetal monitoring during the first stage of labour. In the I-group the fetal heart rate was recorded with electronic fetal monitoring for 10 to 30 min every 2 to 2.5 h during the first stage of labour, and the fetal heart rate was auscultated every 15 to 30 min in between recording periods. If complications occurred, recording was changed to continuous. In the second stage of labour all the women were monitored continuously. Umbilical cord artery acid-base status was assessed at birth.
                Duration of electronic fetal monitoring, rates of abnormal fetal heart rate patterns, caesarean section for fetal distress, acidosis in umbilical cord arterial blood at birth, Apgar scores of less than 7 at 1 or 5 min, and referrals to the neonatal intensive care unit.
                There were no significant differences between the study groups in the incidence of ominous fetal heart rate recordings: 6.3% (I-group) versus 6.6% (C-group), or the interval from arrival to first detected abnormal fetal heart rate, although the number of suspicious fetal heart rate patterns was higher in the C-group (28.6%) than in the I-group (24.6%). In the I-group electronic fetal monitoring was performed for (median monitoring time) 38.8% of the first stage of labour as compared with 78.6% in the C-group. The incidence of caesarean section for fetal distress was similarly low in both groups: 1.2% versus 1.0%. There were no significant differences in the immediate neonatal outcome in terms of umbilical artery pH, Apgar scores, or admissions to the neonatal care unit.
                Intermittent use of electronic fetal monitoring at regular intervals (with stethoscopic auscultation in between) appears to be as safe as continuous electronic fetal monitoring in low risk labours. Screening and monitoring in pregnancy are strategies used by healthcare providers to identify high-risk pregnancies so that they can provide more targeted and appropriate treatment and follow-up care, and to monitor fetal well-being in both low- and high-risk pregnancies. The use of many of these techniques is controversial and their ability to detect fetal compromise often unknown. Theoretically, appropriate management of maternal and fetal risk factors and complications that are detected in pregnancy and labour could prevent a large proportion of the world's 3.2 million estimated annual stillbirths, as well as minimise maternal and neonatal morbidity and mortality.
                The fourth in a series of papers assessing the evidence base for prevention of stillbirths, this paper reviews available published evidence for the impact of 14 screening and monitoring interventions in pregnancy on stillbirth, including identification and management of high-risk pregnancies, advanced monitoring techniques, and monitoring of labour. Using broad and specific strategies to search PubMed and the Cochrane Library, we identified 221 relevant reviews and studies testing screening and monitoring interventions during the antenatal and intrapartum periods and reporting stillbirth or perinatal mortality as an outcome.
                We found a dearth of rigorous evidence of direct impact of any of these screening procedures and interventions on stillbirth incidence. Observational studies testing some interventions, including fetal movement monitoring and Doppler monitoring, showed some evidence of impact on stillbirths in selected high-risk populations, but require larger rigourous trials to confirm impact. Other interventions, such as amniotic fluid assessment for oligohydramnios, appear predictive of stillbirth risk, but studies are lacking which assess the impact on perinatal mortality of subsequent intervention based on test findings. Few rigorous studies of cardiotocography have reported stillbirth outcomes, but steep declines in stillbirth rates have been observed in high-income settings such as the U.S., where cardiotocography is used in conjunction with Caesarean section for fetal distress.
                There are numerous research gaps and large, adequately controlled trials are still needed for most of the interventions we considered. The impact of monitoring interventions on stillbirth relies on use of effective and timely intervention should problems be detected. Numerous studies indicated that positive tests were associated with increased perinatal mortality, but while some tests had good sensitivity in detecting distress, false-positive rates were high for most tests, and questions remain about optimal timing, frequency, and implications of testing. Few studies included assessments of impact of subsequent intervention needed before recommending particular monitoring strategies as a means to decrease stillbirth incidence. In high-income countries such as the US, observational evidence suggests that widespread use of cardiotocography with Caesarean section for fetal distress has led to significant declines in stillbirth rates. Efforts to increase availability of Caesarean section in low-/middle-income countries should be coupled with intrapartum monitoring technologies where resources and provider skills permit.
Continuous cardiotocography during labour is associated with a reduction in neonatal seizures, but no significant differences in cerebral palsy, infant mortality or other standard measures of neonatal well-being. However, continuous cardiotocography was associated with an increase in caesarean sections and instrumental vaginal births. The challenge is how best to convey these results to women to enable them to make an informed choice without compromising the normality of labour.