***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: Background Intermittent preventive treatment with sulphadoxine-pyrimethamine ( IPTp-SP ) is being implemented in most malaria endemic countries as a st and ard two-doses regimen as it reduces the risk of low birth weight ( LBW ) and the prevalence of maternal anaemia . Nevertheless , where the risk of infection close to delivery is high because of intense transmission , a third IPTp-SP dose may further reduce the negative effects of malaria on pregnancy outcome . Methods Pregnant women in the 2nd or 3rd trimester were r and omized to receive either 2 ( SP2 ) or 3 doses ( SP3 ) of SP . Trained field workers paid home visits to the women for drug administration according to a predefined drug delivery schedule . Women were encouraged to attend their scheduled ANC visits and to deliver at the health facilities where the new-born was weighed . The prevalence of LBW ( < 2500 g ) , severe anaemia ( Hb < 8 g/dL ) and premature birth  was analysed using intention-to-treat ( ITT ) and per- protocol ( PP ) analysis . Results Data from 1274 singleton pregnancies were analysed ( 641 in the SP3 and 633 in the SP2 group ) . The uptake of the intervention appeared to be low . Though the prevalence of LBW in both intervention groups was similar ( adjusted Incident Rate Ratio , AIRR = 0.92 , 95%CI : 0.69 - 1.24 ) in the ITT analysis , the risk of severe anaemia was significantly lower in the SP3 group compared to the SP2 group ( AIRR = 0.38 , 95%CI : 0.16 - 0.90 ) . The PP analysis showed a trend of reduced risk of LBW , severe anaemia and premature delivery in the SP3 group , albeit the difference between two and three IPTp-SP did not reach statistical significance . Conclusion The risk of LBW and severe anaemia tended to be lower in the SP3 group , though this was not statistically significant , probably due to the low uptake of the intervention which reduced the power of the study . Further studies are needed for establishing whether a third SP dose has a real benefit in preventing the negative effects of malaria in pregnancy in setting s where transmission is markedly seasonal To determine the effect of chloroquine chemoprophylaxis during pregnancy on birth weights , a r and omized trial was carried out in 1987 and 1988 in Banfora , Burkina Faso ( West Africa ) . Seven hundred forty-five r and omly selected women treated with chloroquine sulfate were compared to with 719 controls who received no treatment .  In spite of an un question able effect of chloroquine in preventing placental infection ( 4.1 % infected placentas in the treated group versus 19.0 % in the controls ) , the mean difference in birth weights between the two groups ( 6 g ) was not significant . The difference in the proportion of low birth weight ( LBW ) newborn babies in two groups ( 16.3 % versus 16.4 % ) was also not significant . However , there was a strong relationship between placental infection and birth weight ( the mean birth weight difference between infected and uninfected placentas was 113 g , and the proportion of LBW babies was 26.0 % in infected placentas versus 14.8 % in uninfected placentas ) . The small difference in birth weights observed between the two groups may be due to the fact that the prevalence rate of placental infection is low and that prophylaxis is effective only on a portion of the subjects in the treated group . It may also indicate that malaria is only one of several risk factors responsible for LBW . The relatively small increase in birth weight , the expected poor acceptance of mass prophylaxis , and the spreading of chloroquine-resistant Plasmodium strains should be considered before extending malaria chemoprophylaxis to all pregnant women . It might be worth considering to limit prophylaxis to primigravidae BACKGROUND In 2003 , Mali introduced intermittent preventive therapy in pregnancy ( ITPp ) with sulfadoxine-pyrimethamine ( SP ) for the control of malaria in pregnancy , consisting of 2 doses of SP given in the 2nd and 3rd trimester . This widely used regimen , although very effective , leaves many women unprotected from malaria during the last 4-to-8 weeks of gestation , which is a pivotal period for fetal weight gain . The aim of the study was to compare the efficacy and safety of 3-dose versus 2-dose IPTp-SP for the prevention of placental malaria and associated low birth weight ( LBW ) . METHODS We conducted a parallel-group , open-label , individually r and omized controlled superiority trial involving 814 women of all gravidity , enrolled from April 2006 through March 2008 . All women were seen at least 3 times and received either 2 ( n = 401 ) or 3 ( n = 413 ) doses of IPTp-SP . The primary endpoint measured was placental malaria , LBW , preterm births , and maternal anemia were secondary endpoints , and severe maternal skin reactions and neonatal jaundice were safety endpoints . RESULTS Among the 96 % of study subjects who were followed up until delivery , the prevalence of placental malaria was 2-fold lower in the 3-dose group ( 8.0 % ) than in the 2-dose group ( 16.7 % ) ; the adjusted prevalence ratio ( APR ) was 0.48 ( 95 % confidence interval [ CI ] , 0.32 - 0.71 ) . LBW and preterm births were also reduced ; the prevalence of LBW was 6.6 % in the 3-dose group versus 13.3 % in the 2-dose group ( APR , 0.50 ; 95 % CI , 0.32 - 0.79 ) , and the prevalence of preterm births was 3.2 % versus 8.9 % ( APR , 0.37 ; 95 % CI , 0.19 - 0.71 ) . No significant reductions in maternal anemia or differences in safety endpoints were observed . CONCLUSIONS Adding a third dose of ITPp-SP halved the risk of placental malaria , LBW , and preterm births in all gravidae , compared with the st and ard 2-dose regimen , in this area of highly seasonal transmission with low levels of SP resistance . CLINICAL TRIALS REGISTRATION IS RCT N 74189211 BACKGROUND In the context of the increasing resistance to sulfadoxine-pyrimethamine ( SP ) , we evaluated the efficacy of mefloquine ( MQ ) for intermittent preventive treatment during pregnancy ( IPTp ) . METHODS A multicenter , open-label equivalence trial was conducted in Benin from July 2005 through April 2008 . Women of all gravidities were r and omized to receive SP ( 1500 mg of sulfadoxine and 75 mg of pyrimethamine ) or 15 mg/kg MQ in a single intake twice during pregnancy . The primary end point was the proportion of low-birth-weight ( LBW ) infants ( body weight , < 2500 g ; equivalence margin , 5 % ) . RESULTS A total of 1601 women were r and omized to receive MQ (n=802)or SP (n=799).In the modified intention-to-treat analysis , which assessed only live singleton births , 59 ( 8 % ) of 735 women who were given MQ and 72 ( 9.8 % ) of 730 women who were given SP gave birth to LBW infants ( difference between low birth weights in treatment groups , -1.8 % ; 95 % confidence interval [ CI ] , -4.8 % to 1.1 % ] ) , establishing equivalence between the drugs . The per- protocol analysis showed consistent results . MQ was more efficacious than SP in preventing placental malaria ( prevalence , 1.7 % vs 4.4 % of women ; P = .005 ) , clinical malaria ( incidence rate , 26 cases/10,000 person-months vs. 68 cases/10,000 person-months ; P = .007 ) and maternal anemia at delivery ( as defined by a hemoglobin level < 10 g/dL ) ( prevalence , 16 % vs 20 % ; marginally significant at P = .09 ) . Adverse events ( mainly vomiting , dizziness , tiredness , and nausea ) were more commonly associated with the use of MQ ( prevalence , 78 % vs 32 % ; P < 10(-3 ) ) One woman in the MQ group had severe neuropsychiatric symptoms . CONCLUSIONS MQ proved to be highly efficacious -- both clinical ly and parasitologically -- for use as IPTp . However , its low tolerability might impair its effectiveness and requires further investigations Flaws in the design , conduct , analysis , and reporting of r and omised trials can cause the effect of an intervention to be underestimated or overestimated . The Cochrane Collaboration ’s tool for assessing risk of bias aims to make the process clearer and more Clara Menéndez and colleagues conducted a r and omized controlled trial among HIV-positive pregnant women in Kenya , Mozambique , and Tanzania to investigate the safety and efficacy of mefloquine  as intermittent preventative therapy for malaria in women receiving cotrimoxazole prophylaxis and long-lasting insecticide treated nets . Please see later in the article for the Editors ' Background The weekly chemoprophylaxis of malaria during pregnancy with chloroquine ( CQ ) has become problematic with the increasing resistance of Plasmodium falciparum to this drug . There was a need to test the benefits of new strategies over the classical chemoprophylaxis . This study was conducted to provide data to the National Malarial Control Programme for an evidence -based policy change decision making process . It compares the efficacy of two IPT regimens , using chloroquine ( CQ ) or sulphadoxine/pyrimethamine ( SP ) , with the classical chemoprophylaxis regimen using CQ in reducing the adverse outcomes of malaria infection , for the mother and the foetus . Methods Pregnant women attending the first antenatal care visit were r and omly assigned to one of the three treatment regimens . They were subsequently followed up till delivery . Maternal , placental and cord blood sample s were obtained upon delivery to check for P. falciparum infection . Results A total of 648 pregnant women were enrolled in the study . Delivery outcome were available for 423 of them . Peripheral maternal P. falciparum infection at delivery was found in 25.8 % of the women . The proportion of women with maternal infection was significantly lower in the IPTp/SP group than in the CQ group ( P < < 0.000 ) . The prevalence of placental malaria was 18.8 % in the CWC/CQ group ; 15.9 % in the IPTp/CQ group and 10.6 % in the IPTp/SP group . The incidence of LBW ( weigth < 2,500 g ) was significantly higher among infants of mothers in the CWC/CQ group ( 23.9 % ) as compared with those of mothers in the IPTp/CQ ( 15.6 % ) and IPTp/SP ( 11.6 % ) groups ( p = 0.02 ) Conclusion Intermittent preventive treatment with SP has shown clear superiority in reducing adverse outcomes at delivery , as compared with intermittent preventive treatment with CQ and classical chemoprophylaxis with CQ Malarial infection during pregnancy increases the risks of severe sequelae for the pregnant woman and the risk of delivering a low birthweight baby . The aim of this intervention study was to reduce significantly the prevalence of malaria parasitaemia in adolescent parturients in Matola and Boane in Mozambique . The study was focused upon the most malaria-vulnerable group , adolescent nulliparous and primiparous women . After completing the usual antenatal clinic and giving informed consent , 600 pregnant women were r and omly chosen in a double blind manner to one of two regimens comparing the prevailing routine ( placebo ) for malaria prevention with a two dose regimen of sulphadoxine-pyrimethamine ( SP ) . The first dose was given at enrollment with a second dose at the beginning of the third trimester . At delivery maternal and placental malaria parasitaemia as well as birthweight and gestational duration were analysed . At booking the prevalence of malaria parasitaemia was 35.3 % in the placebo group and 30.6 % in the SP group . At the second dose , the prevalence of malaria parasitaemia in the placebo group and SP group was 19.7 % and 8.7 % , respectively . This implies a relative risk ( RR ) of 2.24 with 95 % CI ( 1.34 , 3.75 ) . The corresponding figures at delivery were 13.6 % and 6.3 % with an RR of 2.22 ( 1.07 , 4.60 ) and in placenta 13.3 % and 2.4 % with an RR of 4.87 ( 1.58 , 15.0 ) . Newborns with malaria within 7 days were significantly more frequent in the placebo group , 6.4 % and 0.7 % respectively , with an RR of 6.55 ( 1.20 , 35.7 ) . Almost all ( approximately 98 % ) of the 
    Output:
    
The level of antimalarial drug resistance modified the protective effect of the antimalarial drug used for prevention of LBW during pregnancy .
Conclusion Prophylactic antimalarial drugs and specifically sulfadoxine-pyrimethamine may no longer protect against the risk of LBW in areas of high-level resistance .
In Africa , there are currently no suitable alternative drugs to replace sulfadoxine-pyrimethamine for malaria prevention during pregnancy