***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: Objective To assess the effect of low dose aspirin on  severe pre‐eclampsia  when given to women identified as high risk by abnormal uterine artery Doppler ultrasound Abstract —This study prospect ively investigates the potential influence of low-dose aspirin on blood pressure in pregnant women who were at a higher risk of developing preeclampsia than that of the general obstetric population and who received aspirin at different times of the day according to their rest-activity cycle . A double-blind , r and omized , controlled trial was conducted in 341 pregnant women ( 181 primipara ) r and omly assigned to 1 of 6 possible groups according to treatment ( either placebo or aspirin , 100 mg/day , starting at 12 to 16 weeks of gestation ) and the time of treatment : on awakening ( time 1 ) , 8 hours after awakening ( time 2 ) , or before bedtime ( time 3 ) . Blood pressure was automatically monitored for 48 consecutive hours every 4 weeks from the day of recruitment until delivery , as well as at puerperium . There was no effect of aspirin on blood pressure at time 1 ( compared with placebo ) . A blood pressure reduction was highly statistically significant when aspirin was given at time 2 and , to a greater extent , at time 3 ( mean reductions of 9.7/6.5 mm Hg in 24-hour mean for systolic/diastolic blood pressure at the time of delivery as compared with placebo given at bedtime ) . Differences in blood pressure among women receiving aspirin at different circadian times disappeared at puerperium ( P > 0.096 ) . Results indicate a highly significant effect of aspirin on blood pressure that is markedly dependent on the time of aspirin administration with respect to the rest-activity cycle . Timed use of aspirin at low dose effectively contributes to blood pressure control in women at high risk for preeclampsia The aim of this prospect i ve study was to investigate the ability of transvaginal power Doppler ultrasonography to assess the relationship between follicular vascularity and outcome in women undergoing in-vitro fertilization . Each of 38 subjects underwent a single transvaginal power Doppler ultrasound scan on the day of oocyte collection , where the vascularity of individual ovarian follicles was assessed , using a subjective system , and grade d 1 to 4 . In addition , conventional pulsatility indices ( PI ) of the uterine and intra-ovarian ( stromal ) arteries were calculated , which showed no significant differences between the pregnant and non-pregnant groups . Using power Doppler ultrasonography , a total of 188 follicles was studied . The follicular vascularity grade was found to be independent of follicular size and there was no significant difference in fertilization rates with different degrees of vascularity , although there was a trend towards higher fertilization rates with higher grade vascularity . There were 10 pregnancies , giving a pregnancy rate of 26.3 % per embryo transfer . Pregnancies were confined to those women whose embryos were derived from follicles with grade 3 and 4 vascularity ( pregnancy rates per embryo transfer of 12.5 and 61.5 % respectively ) , with only those from grade 4 follicles result ing in livebirths . This preliminary study suggested that high grade follicular vascularity is associated with increased pregnancy rate and that there is a possible link between follicular vascularity and implantation potential Summary : The purpose of this study was to investigate the hypothesis that maternal administration of lOOmg aspirin each day will improve birth‐weight and other measures of neonatal size when given as a treatment to pregnancies complicated by fetal growth restriction and umbilical‐placental insufficiency . A r and omized , double‐blind , placebo controlled study design was employed ; 51 pregnant women were enrolled . The entry criteria were a fetal abdominal circumference < 10th per centile together with an umbilical artery Doppler systolic/diastolic ratio > 95th per centile between 28 and 36 weeks'gestation . Compliance was assessed by serial measurement of maternal serum thromboxane B2 levels . The mean gestational age at enrolment was 32 weeks and at delivery was 36 weeks . There were no differences between the 2 groups in gestational age at birth ; birth‐weight or birth‐weight ratio ; circumferences of the head , chest or abdomen ; skin fold thicknesses ; or neonatal morbidity . Low dose aspirin therapy did not alter Doppler systolic/diastolic ratios . After 14 days therapy , mean thromboxane B2 levels fell more than 80 % from baseline values ; 10.5 % of women did not demonstrate biochemical confirmation of aspirin ingestion , despite verbal confirmation of compliance . We conclude that low dose aspirin therapy is not of benefit in the treatment of pregnancies complicated by fetal growth restriction and umbilical‐placental insufficiency between 28 and 36 weeks ' gestation In a prospect i ve , r and omized , double-blind study for the prevention of  pregnancy-induced hypertension and preeclampsia , 41 primigravidae with positive roll-over test ( 28th-32nd week of pregnancy ) received 80 mg aspirin/day or placebo until the end of the 37th week . In the patients treated with acetylsalicylic acid ( n = 22 ) , 3 cases of proteinuria occurred , but no hypertensive pregnancy complication . In the placebo group ( n = 19 ) , 10 patients developed  pregnancy-induced hypertension ( 6 of them preeclampsia ) . Group-specific differences concerning the occurrence of hypertension were statistically highly significant ( p = 0.0004 ) . No relevant differences were observed with regard to pregnancy duration , birth weight and umbilical artery pH value . The placebo group included 1 intrauterine death . No increased tendency to maternal or fetal bleeding was noticed OBJECTIVES The aims of this prospect i ve study were to explore the changes in platelet angiotensin II ( A-II ) binding in pregnancy amongst Chinese women at high risk of developing pregnancy-induced hypertension ( PIH ) and the effects of low-dose aspirin and calcium supplementation on A-II binding . METHODS Platelet A-II binding was assayed in 15 non-pregnant women and in 63 pregnant women determined to be at risk of PIH on the basis of 2nd-trimester mean arterial pressure ( MAP ) . The pregnant patients were r and omized into three groups : control , low-dose aspirin , and calcium supplementation .  A-II binding was assayed again during the 3rd trimester in half the women and 8 weeks after delivery . RESULTS A-II binding was negatively correlated with MAP measured in the left lateral position ( p < 0.05 ) but not with MAP measured in the supine position . There were no significant differences between A-II binding in non-pregnant and pregnant women . Neither low-dose aspirin nor calcium supplementation caused significant reductions in A-II binding . CONCLUSION The measurement of platelet A-II binding is unlikely to provide significant information regarding the risk of PIH over and above that obtained from measurement of 2nd-trimester MAP Pre-eclampsia is a common complication of pregnancy , in which platelets may have an early pathogenetic role . In this prospect i ve study a whole blood flow cytometric method has been used to detect circulating activated platelets in pregnant women prior to the development of pre-eclampsia . Activated platelets were identified by bound fibrinogen or by CD63 antigen expression . Of 121 healthy primiparous women studied at 28 weeks of pregnancy , 18 ( 15 % ) developed  clinical pre-eclampsia  six to thirteen weeks later . The platelets of these women showed increased fibrinogen binding ex vivo ( 5.1 % platelets positive , compared with 3.4 % in those who completed a normal pregnancy , p < 0.02 ) , and increased CD63 antigen expression ( 0.73 % positive compared to 0.45 % , p = 0.01 ) . In contrast , no differences between the women with different outcomes were detected at 28 weeks in platelet counts , or plasma beta-thromboglobulin levels . These findings confirm that whole blood flow cytometry is a sensitive technique for investigating platelet activation in a clinical setting and support the hypothesis that platelets have a critical role in the pathogenesis of pre-eclampsia OBJECTIVE To compare the effect of aspirin and enoxaparin on live births in women with unexplained recurrent miscarriages  , as well as secondary outcomes including birth weight , uterine and umbilical blood flows , and congenital malformations . DESIGN Multicenter r and omized comparative cohort study . SETTING Four centers including two university hospitals , a peripheral general hospital , and a community health clinic . PATIENT(S ) One hundred seven patients were r and omized , 104 were available for analysis ; 54 were r and omized to enoxaparin and 50 to aspirin .  INTERVENTION(S ) Treatment with enoxaparin or aspirin in subsequent pregnancy . MAIN OUTCOME MEASURE(S ) Subsequent live births or miscarriage , and the incidence of obstetric complications . RESULT ( S ) Both groups had a similar live birth rate ( relative risk = 0.92 , 95 % confidence interval : 0.58 - 1.46 ) . In primary aborters , live births occurred in 17 of 18 ( 94 % ) enoxaparin-treated pregnancies compared to 18 of 22 ( 81 % ) aspirin-treated pregnancies . In the aspirin group , two pregnancies were terminated : for tricuspid insufficiency and for hemolysis , elevated liver enzymes , low platelet ( HELLP ) syndrome . One enoxaparin-treated infant was growth restricted ( 2,020 g ) at 36 weeks . Preeclampsia was found in three aspirin-treated patients . Preterm delivery , placental Doppler blood flow , apgar scores , and mean birth weights were similar in both groups . In the aspirin group , one infant underwent orchidectomy after testicular torsion in utero , and one infant had hypoglycemia and convulsions . CONCLUSION ( S ) Both regimens were associated with a high live birth rate and few late pregnancy complications Objectives Concern has been expressed about possible neonatal side effects after the use of maternal anti‐platelet agents in pregnancy , particularly low dose aspirin treatment . We have studied  neonatal platelet behaviour using whole blood techniques , and assessed the neonatal effect of the maternal ingestion of 60 mg aspirin daily Screening of 1226 nulliparous women by means of doppler uteroplacental flow-velocity waveforms in early pregnancy identified 148 ( 12 % ) as being at high risk of pregnancy-induced hypertension . After exclusions and refusals , 100 women were r and omly allocated to groups receiving either low-dose aspirin ( 75 mg daily ; 48 patients ) or identical placebo ( 52 patients ) for the remainder of the pregnancy . The difference between the aspirin and placebo groups in the frequency of pregnancy-induced hypertension ( 13 % vs 25 % ) did not achieve significance , but there were significant differences in the frequencies of proteinuric hypertension ( 2 % vs 19 % ) and hypertension occurring before 37 weeks ' gestation ( 0 % vs 17 % ) . Fewer aspirin-treated than placebo-treated women had low birthweight babies ( 15 % vs 25 % ) , but this difference was not significant . The only perinatal death in the aspirin group followed a cord accident during labour , whereas the 3 perinatal deaths in the placebo group were all due to severe hypertensive disease . No maternal or neonatal side-effects were observed in either group Objectives To examine the fetal effects of a novel controlled‐release , low dose aspirin preparation in normal and hypertensive pregnancies Data from literature report that angiotensin-converting enzyme ( ACE ) insertion/deletion ( I/D ) polymorphism affects the recurrence of preeclampsia and that low-molecular-weight heparin ( LMWH ) prevents adverse outcomes in thrombophilic women . We investigated the effect of LMWH on the pregnancy outcome , on maternal blood pressure values , and on uteroplacental flow in ACE DD nonthrombophilic women with history of preeclampsia . Eighty nonthrombophilic ACE DD women were r and omized in 2 groups : 41 treated with  dalteparin 5000 IU/day and 39 untreated ( control group ) . Women underwent 24-hour automated blood pressure monitoring in the preconceptional period and every 2 weeks from weeks 8 to 36 and transabdominal color flow/pulsed Doppler examination at weeks 16 , 20 , and 24 . LMWH reduced the risk of clinical negative outcomes ( 74.1 % reduction of preeclampsia and 77.5 % reduction of fetal growth restriction ) and the severity ( 88.3 % reduction of early onset of preeclampsia and 86.4 % reduction of early onset of fetal growth restriction ) . In treated women , the relative risk for preeclampsia was 0.26 ( P=0.02 ) , and the relative risk for fetal growth restriction was 0.14 ( P<0.001 ) . Systolic ( P=0.002 ) and 
    Output:
    
REVIEW ER 'S CONCLUSIONS Antiplatelet agents , in this review largely low-dose aspirin , have small-moderate benefits when used for prevention of pre-eclampsia .