Third trimester placental grading by ultrasonography as a test of fetal wellbeing. Routine ultrasound fetal examination in pregnancy: the 'Alesund' randomized controlled trial. A randomized controlled trial in a hospital population of ultrasound measurement screening for the small for dates baby. The effects of ultrasound examination on maternal anxiety levels. Randomized trial of endovaginal ultrasound in preterm premature rupture of membranes. Doppler flow velocity waveform analysis in high risk pregnancies: a randomized controlled trial. Effect of prenatal ultrasound screening on perinatal outcome. RADIUS Study Group. Screening for small for dates fetuses: a controlled trial. Randomized comparison of routine vs highly selective use of Doppler ultrasound and biophysical scoring to investigate high risk pregnancies.
In a study of 2000 unselected pregnant women the development of a mature placental appearance (grade 3) on ultrasonography by 34-36 weeks' gestation, observed in 15% of cases, was associated with maternal smoking, low parity, low maternal age, and being white. These women had an increased risk of problems during labour and their babies had an increased risk of low birth weight, poor condition at birth, and perinatal death. The women were randomly allocated to two groups: in one group the result of the placental grading was reported to the clinician responsible for care; in the second the result was noted but not reported. There was a significant decrease in the risk of perinatal death in the group where the grading was known. This reduction was responsible for a difference in the principal outcome index, a heterogeneous group of measures of mortality and morbidity, but this difference was not significant. This study alone does not justify routine late scanning, and further, larger trials are required. Nevertheless, the results do provide a basis for the reporting of placental grading when ultrasound examination is performed during the third trimester. To evaluate the possible benefits of the routine use of ultrasound screening in pregnancy.
                A randomized controlled trial was designed to detect a 50% difference in the incidence of induction for apparent post-term pregnancies between women who were screened with ultrasound and unscreened women. A total of 1628 pregnant women from the general population were included. Eight hundred and twenty-five were allocated to an ultrasound examination at the 18th and 32nd week of pregnancy in addition to receiving routine antenatal care. The remaining 803 women received standard antenatal care, but could only be referred for ultrasound examination on clinical indication.
                The incidence of induced labor due to apparent post-term pregnancies was approximately 70% lower in the ultrasound-screened group. Inductions from all causes were also less frequent among ultrasound-screened women. There were six perinatal deaths among the screened and seven among the controls after excluding three lethal malformations among the controls. There was no difference in Apgar score after 1 min, but the proportion with Apgar score less than 8 after 5 min was lower among the screened group (P = 0.04). The need for positive pressure ventilation for more than 1 min was lower among the screened group (P = 0.02). Birth weight was slightly higher in the screened group (39 g), but the difference was not statistically significant. Among the controls three pairs of twins remained undiagnosed until the mothers were admitted to the hospital in labor at between 36 and 38 weeks gestation.
                These results suggest that for women who were screened with ultrasound, obstetricians were less likely to induce labor due to apparent post-term pregnancy, than for women who were not screened. All 10 pairs of twins in the screened group were diagnosed at the routine examination. These data also suggest that perinatal morbidity might be slightly lower in the screened group. Poor fetal growth is an important cause of perinatal mortality and morbidity. Based on the hypothesis that early diagnosis of fetal growth problems leads to more appropriate management and therefore, improved outcome, a randomized controlled trial of ultrasound measurement was performed on 1,528 women booked through a hospital antenatal clinic. This compared a number of perinatal outcomes between the group who had a routine 2-stage examination (early dating and 34-week scan) and a group who had only a dating scan and then additional scans as generated by their clinical situations. No significant differences could be found between the groups when these perinatal outcomes were considered. These results mirror previously published randomized controlled trials. Selection of women for third trimester ultrasound examination for suspected fetal growth problems should be based on careful clinical assessment and should not be routine. A study has been conducted to assess the psychological effects of real-time ultrasound on the pregnant woman's attitudes and anxiety levels. A consecutive series of primiparae, fulfilling the selection criteria of obstetrically "low risk," was assigned at random to two conditions of ultrasound, namely, (a) high feedback (N = 67), where the woman saw the moving fetus in utero; and (b) low feedback (N = 62), where the monitor screen was not visible and no specific feedback was provided. A third group of women was assessed following a wait period in order to compare state anxiety levels among the three groups. Attitude assessments showed consistent preultrasound-post-ultrasound change, with more uniformly positive attitudes displayed by the high-feedback group. No between-group differences in state anxiety emerged as a result of ultrasound compared with a wait control period. No differences emerged with respect to anticipatory anxiety measures. The results are considered in the context of evidence on the importance of psychological state on the course and outcome of pregnancy. It is suggested that the low-risk characteristics of this sample may have precluded effects on anxiety and it is concluded that the therapeutic potential of ultrasound warrants further study. To assess the effect of weekly endovaginal ultrasound on the incidence of maternal infection and the time from rupture to delivery in women with preterm premature rupture of membranes (PROM).
                Women with singleton pregnancies complicated by preterm PROM at 24-34 weeks' gestation were assigned randomly to groups having endovaginal ultrasound or no vaginal sonography. Along with the standard expectant management, the endovaginal-ultrasound group had weekly vaginal probe ultrasound scans. Power analysis based upon expected maternal infection required a sample size of 45 patients in each group.
                Forty-seven and 45 subjects were assigned to the no-probe and probe groups, respectively. The latency period, defined as days from rupture to delivery, was 9.8 and 11.7 days for the no-probe and probe groups, respectively (95% confidence interval -5.9, 2.1). There were no significant differences in the incidence of chorioamnionitis (28% and 20%), endometritis (6% and 9%), or neonatal infection (17% and 20%). The mean latency period in women who went into spontaneous labor and whose initial cervical length was 3.0 cm or less was 9.4 days, compared with 11.0 days if the cervix exceeded 3.0 cm, a nonsignificant difference. There were three neonatal deaths, all in the probe group and none directly related to infection.
                Endovaginal ultrasound in patients whose pregnancies are complicated by preterm PROM does not appear to increase the incidence of maternal infection. To test whether the introduction of Doppler waveform analysis into the ultrasound department of a tertiary level hospital reduces neonatal morbidity and improves obstetric management.
                A randomized controlled trial.
                Department of Ultrasound, King Edward Memorial Hospital, Perth, Western Australia.
                505 women with pregnancy abnormalities referred to an ultrasound department for fetal investigation during the third trimester.
                Continuous wave Doppler studies of umbilical and uteroplacental arterial circulations. Results were revealed to patients and clinicians.
                Principal end point was the duration of neonatal stay in hospital; other end points included the number and type of fetal heart rate monitoring studies, obstetric interventions, frequency of fetal distress, birthweight, Apgar scores and need for neonatal intensive care.
                There was no effect on the duration of neonatal stay in hospital. Small trends in obstetric management were observed with study group patients having fewer contraction stress tests, less likelihood of antepartum fetal distress, and more likelihood of fetal distress after induction of labour leading to emergency caesarean section. Depressed Apgar scores were more frequent in the study group.
                Introduction of Doppler waveform studies did not result in reduced neonatal morbidity but did have a small effect on obstetric management. For each institution the role of Doppler studies in late pregnancy will be influenced by the usage of other tests of fetal welfare already entrenched in clinical practice. Many clinicians advocate routine ultrasound screening during pregnancy to detect congenital anomalies, multiple-gestation pregnancies, fetal growth disorders, placental abnormalities, and errors in the estimation of gestational age. However, it is not known whether the detection of these conditions through screening leads to interventions that improve perinatal outcome.
                We conducted a randomized trial involving 15,151 pregnant women at low risk for perinatal problems to determine whether ultrasound screening decreased the frequency of adverse perinatal outcomes. The women randomly assigned to the ultrasound-screening group underwent one sonographic examination at 15 to 22 weeks of gestation and another at 31 to 35 weeks. The women in the control group underwent ultrasonography only for medical indications, as identified by their physicians. Adverse perinatal outcome was defined as fetal death, neonatal death, or neonatal morbidity such as intraventricular hemorrhage.
                The mean numbers of sonograms obtained per woman in the ultrasound-screening and control groups were 2.2 and 0.6, respectively. The rate of adverse perinatal outcome was 5.0 percent among the infants of the women in the ultrasound-screening group and 4.9 percent among the infants of the women in the control group (relative risk, 1.0; 95 percent confidence interval, 0.9 to 1.2; P = 0.85). The rates of preterm delivery and the distribution of birth weights were nearly identical in the two groups. The ultrasonographic detection of congenital anomalies had no effect on perinatal outcome. There were no significant differences between the groups in perinatal outcome in the subgroups of women with post-date pregnancies, multiple-gestation pregnancies, or infants who were small for gestational age.
                Screening ultrasonography did not improve perinatal outcome as compared with the selective use of ultrasonography on the basis of clinician judgment. In the hope of reducing perinatal risks associated with retardation of intrauterine growth a previously described two stage ultrasound screening schedule was evaluated by a controlled trial in 877 women with low risk single pregnancies. The two stages of ultrasound examination were an assessment of gestational age during early pregnancy followed by measurement of length from crown to rump and area of trunk at between 34 and 36 weeks' gestation. The product of crown to rump length and trunk area was calculated. The sensitivity of this schedule in identifying in advance 94% of babies who were small for dates at birth, with 90% specificity, and the speed and simplicity of measurement confirmed the accuracy and feasibility of two stage ultrasonography as a screening procedure. The controlled trial did not, however, show any benefit from its routine application in these low risk pregnancies. To compare routine versus highly selective use of Doppler ultrasound and biophysical scoring in higher risk pregnancy.
                A pragmatic randomized trial.
                St James's University Hospital, Leeds.
                500 pregnant women at high risk of intrauterine growth retardation or still birth.
                Regular monitoring with biophysical profile assessment and Doppler velocity waveform recording in umbilical and uteroplacental arteries. Results immediately available to clinicians.
                Gestational age at delivery, obstetric intervention rates and short-term neonatal morbidity.
                Risk factors were distributed very evenly between the 250 patients in the study and control groups respectively. A total of 902 biophysical profile and Doppler assessments were done in the 250 study group patients and only in 12 patients in the control group. In the study group, absent end-diastolic flow was found in only 2.7% of all 902 measurements. A persistently abnormal biophysical score was always associated with absence of end-diastolic flow. The mean gestational age at induction of labour was statistically and clinically similar in the two groups and there was no overall statistically significant difference in intervention rates between the two groups. There was a statistically significant lower frequency of depressed 5-min Apgar scores in the study group. Serious neonatal morbidity was also statistically significantly more common in the control group than in the study group.
                The use of Doppler ultrasound in higher risk pregnancies does not lead to an increase in iatrogenic preterm delivery. The total rate of positive tests on Doppler ultrasound is very low and persistently abnormal biophysical scores are unlikely to be found in patients where umbilical end-diastolic blood flow is present. Surrogate measures for fetal damage seem to be improved when clinicians have access to Doppler ultrasound assessments.
Based on existing evidence, routine late pregnancy ultrasound in low-risk or unselected populations does not confer benefit on mother or baby. It may be associated with a small increase in caesarean section rates. There is a lack of data about the potential psychological effects of routine ultrasound in late pregnancy, and limited data about its effects on both short- and long-term neonatal and childhood outcome. Placental grading in the third trimester may be valuable, but whether reported results are reproducible remains to be seen, and future research of late pregnancy ultrasound should include evaluation of placental textural assessment.