***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 
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    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 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 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 OBJECTIVE We conducted a large clinical trial to evaluate the effect of low-dose aspirin on the frequency of  preeclampsia in nulliparous women . A secondary objective of the trial was to identify those clinical characteristics that might be predictive for the development of preeclampsia . STUDY DESIGN A total of 2947 healthy women with a single fetus were prospect ively followed up from r and omization at 13 to 27 weeks ' gestation to the end of pregnancy . Of these , 1465 women were assigned to low-dose aspirin and 1482 to placebo . Baseline maternal blood pressure and demographic characteristics were examined for the prediction of preeclampsia . RESULTS Preeclampsia developed in 156 women ( 5.3 % ) . Four characteristics predicted the development of preeclampsia : in order of importance , systolic blood pressure at entry , prepregnancy obesity ( weight as a percentage of desirable weight ) , number of previous abortions or miscarriages , and smoking history . Contrary to previous reports , black race was not a risk factor for preeclampsia . Systolic blood pressure was a better predictor of preeclampsia than either diastolic or mean arterial blood pressure . The greater the blood pressure or prepregnancy weight , the greater was the risk for preeclampsia . If the woman had never smoked or had never been previously pregnant , her risk was also higher than average . A multivariate logistic regression equation based on these four factors was able to define a tenth of the population at very high risk and another tenth at very low risk ; the ratio of risk between these two groups was 12:1 . The p value for each of the multivariate coefficients of the risk equation was systolic blood pressure ( p < 0.001 ) , prepregnancy weight ( p < 0.01 ) , smoking history ( p < 0.01 ) , and gravidity ( p < 0.05 ) . There were no statistically significant differences in the predictive values of these risk factors between women receiving low-dose aspirin or placebo . CONCLUSIONS These risk factors should be of value to practitioners counseling women regarding preeclampsia . Moreover , such risk factors should be considered in the design of future studies dealing with preeclampsia A prospect i ve study conducted between January , 1985 and September , 1987 involved 60 pregnant women who had previously suffered from hypertension in pregnancy with or without foetal and maternal complications . Thirty women received aspirin 250 mg every other day and dipyridamole 300 mg per day , starting from the 3rd month of pregnancy ( group I ) ; 30 women were examined regularly from the onset of pregnancy and received the conventional symptomatic treatment of complications that occurred ( group II ) . Women in these two groups were similar in age , parity and previous obstetrical complications . Twenty-five women of group I had a perfectly normal pregnancy , as against 5 women of group II ( P less than 0.001 ) . Hypertension and /or proteinuria were observed in 5 women of group I and 15 of group II ( NS ) . The 13 severe complications recorded ( foetal death , eclampsia , retroplacental haematoma ) occurred exclusively in women of group II . The duration of pregnancy and weight of the newborn were significantly greater in group I than in group II . Thus , antiplatelets appear to have an uncertain preventive effect on hypertension of pregnancy and a much more obvious prophylactic effect on major foetal and maternal complications BACKGROUND Although low-dose aspirin has been reported to reduce the incidence of preeclampsia among women at high risk for this complication , its efficacy and safety in healthy , nulliparous pregnant women are not known . METHODS We studied 3135 normotensive nulliparous women who were 13 to 26 weeks pregnant to determine whether treatment with aspirin reduced the incidence of preeclampsia . Of this group , 1570 women received 60 mg of aspirin per day and 1565 received placebo for the remainder of their pregnancies . We also evaluated the effect of  aspirin  on maternal and neonatal morbidity . RESULTS Of the original group of 3135 women , 2985 ( 95 percent ) were followed throughout pregnancy and the immediate puerperium . The incidence of preeclampsia was lower in the aspirin group ( 69 of 1485 women [ 4.6 percent ] ) than in the placebo group ( 94 of 1500 women [ 6.3 percent ] ) ( relative risk , 0.7 ; 95 percent confidence interval , 0.6 to 1.0 ; P = 0.05 ) , whereas the incidence of gestational hypertension was 6.7 and 5.9 percent , respectively . There were no significant differences in the infants ' birth weight or in the incidence of fetal growth retardation , postpartum hemorrhage , or neonatal bleeding problems between the two groups . Subgroup analysis showed that preeclampsia occurred primarily in women whose initial systolic blood pressure was 120 to 134 mm Hg ( incidence among such women , 5.6 percent in the aspirin group vs. 11.9 percent in the placebo group ; P = 0.01 ) . The incidence of abruptio placentae was greater among the women who received aspirin ( 11 women , vs. 2 in the placebo group ; P = 0.01 ) . CONCLUSIONS Low-dose aspirin decreases the incidence of preeclampsia among nulliparous women , primarily through its effect in those who have elevated systolic blood pressure initially . This treatment does not decrease perinatal morbidity but increases the risk of abruptio placentae This study investigated the effects of low-dose acetylsalicylic acid ( aspirin ) on blood pressure in pregnant women who were at risk of developing gestational hypertension or preeclampsia 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 100 pregnant women .  Blood pressure for each subject was automatically monitored for 2 days every 4 weeks from the day of recruitment until delivery . Women were r and omly assigned to one of six groups according to treatment ( placebo , 50 subjects or aspirin , 100 mg/d , 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 ) . Results indicated that there was ( 1 ) no effect on blood pressure from placebo at any time ( P>.212 ) and ( 2 ) a highly statistically significant ( P<.001 ) time-dependent effect on blood pressure from aspirin . There was no effect of aspirin on blood pressure at time 1 ( compared 
    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 .