***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: To comprehend the results of a r and omised controlled trial ( RCT ) , readers must underst and its design , conduct , analysis , and interpretation . That goal can be achieved only through total transparency from authors . Despite several decades of educational efforts , the reporting of RCTs needs improvement . Investigators and editors developed the original CONSORT ( Consoli date d St and ards of Reporting Trials ) statement to help authors improve reporting by use of a checklist and flow diagram . The revised CONSORT statement presented here incorporates new evidence and addresses some criticisms of the original statement . The checklist items pertain to the content of the Title , Abstract , Introduction , Methods , Results , and Discussion . The revised checklist includes 22 items selected because empirical evidence indicates that not reporting this information is associated with biased estimates of treatment effect , or because the information is essential to judge the reliability or relevance of the findings . We intended the flow diagram to depict the passage of participants through an RCT . The revised flow diagram depicts information from four stages of a trial ( enrolment , intervention allocation , follow- up , and analysis ) . The diagram explicitly shows the number of participants , for each intervention group , included in the primary data analysis . Inclusion of these numbers allows the reader to judge whether the authors have done an intention- to-treat analysis . In sum , the CONSORT statement is intended to improve the reporting of an RCT , enabling readers to underst and a trial 's conduct and to assess the validity of its results OBJECTIVES We sought to document the pregnancy and neurodevelopmental outcome in monochorionic diamniotic twin pregnancies and to identify risk factors for death and impairment . STUDY DESIGN We conducted a prospect i ve cohort study of 136 monochorionic twins followed up from the first trimester until infancy . RESULTS A total of 122 ( 90 % ) pregnancies result ed in 2 survivors , 6 ( 4 % ) in 1 survivor and 8 ( 6 % ) in no survivor . In all , 230 ( 92 % ) of 250 surviving infants were assessed at a mean age of 24 months . Neurodevelopmental impairment was present in 22 ( 10 % ) infants . Death or impairment of 1 or both infants occurred in 28 ( 22 % ) of 126 pregnancies . Twin-to-twin transfusion syndrome and assisted conception increased the risk of both death and impairment , whereas early-onset discordant growth only increased the risk of death . CONCLUSION The mortality in this prospect i ve series was 8 % and neurodevelopmental impairment occurred in 10 % of infants After the adoption of the use of umbilical artery and middle cerebral artery peak systolic velocity in high-risk pregnancies and in pregnancies that are at risk of having an anemic fetus , the main focus of Doppler ultrasonography in obstetrics today is intrauterine growth-restricted fetuses . What is most needed at this time are ( 1 ) training of sonographers and sonologists on how to perform a Doppler study , ( 2 ) an international classification of intrauterine growth-restricted fetuses , and ( 3 ) a study of the natural history of intrauterine growth-restricted fetuses that might contribute to a better underst and ing of the intrauterine growth-restriction process and to st and ard treatment of intrauterine growth-restricted fetuses . Future investigations , which would include r and omized studies , could be design ed from the results of such studies We have done a r and omised controlled trial to assess the effect on primary management and outcome of routine doppler ultrasound examinations of the umbilical and uterine arteries during pregnancy . Over 9 months , 2600 women with singleton pregnancies were recruited from a general obstetric population . Of 2475 women who delivered in hospital after 20 weeks ' gestation , 1246 had been allocated at r and om to receive st and ard antenatal care with routine doppler examinations . The first doppler ultrasound was done at 19 - 22 weeks ' gestation , and thereafter examinations were monthly if the pregnancy was considered high risk ( 192 ) or once at 32 weeks if considered low risk ( 1054 ) . The control group of 1229 women received  st and ard , antenatal care without doppler ultrasonography . The study groups did not differ in number of antenatal admissions or cardiotocographs , gestational age at delivery , method of delivery , frequency of deliveries with fetal distress , or need for resuscitation or admission to the neonatal intensive care unit . More perinatal deaths occurred in the doppler group ( 17 vs 7 , relative risk 2.4 , 95 % Cl 1.00 - 5.76 ) , but only 1 of 11 normally formed stillbirths and none of the 4 normally formed neonatal deaths after 24 weeks ' gestation had an abnormal umbilical-artery doppler examination . We did not demonstrate any improvement in neonatal outcome by routine doppler ultrasound screening of a general obstetric population One-hundred and eighty-seven single pregnancies , at full term determined accurately and confirmed by ultrasound before 17 weeks of amenorrhea and which were proceeding normally were monitored every 2 days after the expected end of term . This was done by conventional methods and in 132 cases by determining a placental resistance  index ( R = D/S ) . All the deliveries were carried out under monitoring and the infants examined by a pediatrician . The umbilical index at 280 to 300 days of gestation was found to be constant and equal to R = 0.52 + /- 0.041 ( n + /- D ) and the signs of fetal distress and post-maturity increased beyond term . In the first 80 pregnancies studies in this way , the determination of the value of the index R was not included in the decision-making process . Twelve of the 14 cases of fetal heart rate arrhythmia during delivery and all recorded cases of post-mature clinical signs and neonatal acidosis occurred when the index was above RI = 0.54 . The next 107 pregnancies were r and omly divided into two groups . In the 52 pregnancies in which the Doppler revealed an index at two consecutive determinations in excess of 0.54 , this was taken to be a criterion for the induction of childbirth . In this group , some of the women gave birth earlier , without any increase in the number of Caesareans and this result ed in fewer post-mature infants . ( ABSTRACT TRUNCATED AT 250 WORDS BACKGROUND No consensus exists for the best way to monitor and when to trigger delivery in mothers of babies with fetal growth restriction . We aim ed to assess whether changes in the fetal ductus venosus Doppler waveform ( DV ) could be used as indications for delivery instead of cardiotocography short-term variation ( STV ) . METHODS In this prospect i ve , European multicentre , unblinded , r and omised study , we included women with singleton fetuses at 26 - 32 weeks of gestation who had very preterm fetal growth restriction ( ie , low abdominal circumference [ < 10th percentile ] and a high umbilical artery Doppler pulsatility index [ > 95th percentile ] ) . We r and omly allocated women 1:1:1 , with r and omly sized blocks and stratified by participating centre and gestational age ( < 29 weeks vs ≥29 weeks ) , to three timing of delivery plans , which differed according to antenatal monitoring strategies : reduced cardiotocograph fetal heart rate STV ( CTG STV ) , early DV changes ( pulsatility index > 95th percentile ; DV p95 ) , or late DV changes ( A wave [ the deflection within the venous waveform signifying atrial contraction ] at or below baseline ; DV no A ) . The primary outcome was survival without cerebral palsy or neurosensory impairment , or a Bayley III developmental score of less than 85 , at 2 years of age . We assessed outcomes in surviving infants with known outcomes at 2 years . We did an intention to treat study for all participants for whom we had data . Safety outcomes were deaths in utero and neonatal deaths and were assessed in all r and omly allocated women . This study is registered with IS RCT N , number 56204499 . FINDINGS Between Jan 1 , 2005 and Oct 1 , 2010 , 503 of 542 eligible women were r and omly allocated to monitoring groups ( 166 to CTG STV , 167 to DV p95 , and 170 to DV no A ) . The median gestational age at delivery was 30·7 weeks ( IQR 29·1 - 32·1 ) and mean birthweight was 1019 g ( SD 322 ) . The proportion of infants surviving without neuroimpairment did not differ between the CTG STV ( 111 [ 77 % ] of 144 infants with known outcome ) , DV p95 ( 119 [ 84 % ] of 142 ) , and DV no A ( 133 [ 85 % ] of 157 ) groups ( ptrend=0·09 ) . 12 fetuses ( 2 % ) died in utero and 27 ( 6 % ) neonatal deaths occurred . Of survivors , more infants where women were r and omly assigned to delivery according to late ductus changes ( 133 [ 95 % ] of 140 , 95 % , 95 % CI 90 - 98 ) were free of neuroimpairment when compared with those r and omly assigned to CTG ( 111 [ 85 % ] of 131 , 95 % CI 78 - 90 ; p=0.005 ) , but this was accompanied by a non-significant increase in perinatal and infant mortality . INTERPRETATION Although the difference in the proportion of infants surviving without neuroimpairment was non-significant at the primary endpoint , timing of delivery based on the study protocol using late changes in the DV waveform might produce an improvement in developmental outcomes at 2 years of age . FUNDING ZonMw , The Netherl and s and Dr Hans Ludwig Geisenhofer Foundation , Germany OBJECTIVE To identify the temporal sequence of abnormal Doppler changes in the fetal circulation in a subset of early and severely growth-restricted fetuses . METHODS This was a prospect i ve observational study in a tertiary care/teaching hospital . Twenty-six women who were diagnosed with growth-restricted fetuses by local st and ards before 32 weeks ' gestation and who had abnormal uterine and umbilical artery Doppler velocimetry were enrolled onto the study . To compare Doppler changes as a function of time , pulsed-wave Doppler ultrasound was performed on five vessels in the fetal peripheral and central circulations . Doppler examinations were performed twice-weekly and on the day of delivery if the fetal heart rate tracing became abnormal . Doppler indices were scored as abnormal when their values were outside the local reference limits on two or more consecutive measurements . Biometry for assessment of fetal growth was performed every 2 weeks . Computerized fetal heart rates were obtained daily . Delivery was based on a non-reactive fetal heart rate tracing and not on Doppler information . Patients with a severely growth-restricted fetus who were delivered for maternal indications such as pre-eclampsia were excluded . Perinatal outcome endpoints included : intrauterine death , gestational age at delivery , newborn weight , central nervous system damage of grade 2 or greater , intraventricular hemorrhage and neonatal mortality . RESULTS Mean gestational age and newborn weight at delivery were 29 ( st and ard deviation ( SD ) , 2 ) weeks and 818 ( SD , 150 ) g , respectively . The sequence of Doppler velocimetric changes was described by onset time cumulative curves that showed two time-related events . First , for each vessel there was a progressive increase in the percent of fetuses developing a Doppler abnormality . Second , severely growth-restricted fetuses followed a progressive sequence of acquiring Doppler abnormalities which were categorized into ' early ' and ' late ' Doppler changes . Early changes occurred in peripheral vessels ( umbilical and middle cerebral arteries ; 50 % of patients affected 15 - 16 days prior to delivery ) . Late changes included umbilical artery reverse flow , and abnormal changes in the ductus venosus , aortic and pulmonary outflow tracts ( 50 % of patients affected 4 - 5 days prior to delivery ) . The time interval between the occurrence of early and late changes was significantly different ( P < 0.0001 ) and late changes were significantly associated with perinatal death ( P < 0.01 ) . CONCLUSIONS Doppler velocimetry abnormalities develop in different vessels of the severely growth-restricted fetus in a sequential fashion . Late changes in vascular adaptation by the severely growth-restricted fetus are the best predictor of perinatal death Abstract Despite widespread application of ultrasound imaging and Doppler blood flow studies , the effects of their frequent and repeated use in pregnancy have not been evaluated in controlled trials . From 2834 women with single pregnancies at 16 - 20 weeks gestation , 1415 were selected at r and om to receive ultrasound imaging and continuous-wave Doppler flow studies at 18 , 24 , 28 , 34 , and 38 weeks gestation ( the intensive group ) and 1419 to receive single ultrasound imaging at 18 weeks ( the regular group ) . Outcome data was obtained from 99 % of women who entered the study . The only difference between the two groups was significantly higher intrauterine growth restriction in the intensive group , when expressed both as 
    Output:
    
Data for serious neonatal morbidity were not pooled due to high heterogeneity between the three studies that reported it ( 1098 babies ) ( evidence grade d very low).The use of Doppler to evaluate early and late changes in ductus venosus in early fetal growth restriction was not associated with significant differences in any perinatal death after r and omisation .
However , there was an improvement in long-term neurological outcome in the cohort of babies in whom the trigger for delivery was either late changes in ductus venosus or abnormalities seen on computerised CTG .
Current evidence suggests that the use of Doppler ultrasound on the umbilical artery in high-risk pregnancies reduces the risk of perinatal deaths and may result in fewer obstetric interventions .