***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: Preterm premature rupture of membranes ( PPROM ) complicates 3 % of pregnancies and frequently results in preterm birth , often within 48 hours of membrane rupture . Our objective was to determine if subjects with PPROM between 24 and 31 (6)/ ( 7 ) weeks ' gestation benefit from a 48-hour course of prophylactic indomethacin tocolysis . This was a double-masked r and omized controlled trial . Subjects with PPROM between 24 and 31 (6)/ ( 7 ) weeks ' gestation were r and omized to receive indomethacin or placebo for 48 hours in addition to corticosteroids and latency antibiotics . The primary outcome of the study was delivery within 48 hours . Maternal and neonatal outcomes were also compared . This study was concluded prematurely due to slow accrual after a total of 50 subjects were enrolled . A total of 23/25 ( 92 % ) subjects in the indomethacin group remained pregnant beyond 48 hours compared with 20/22 ( 90.9 % ) in the placebo group ( relative risk , 1.01 ; 95 % confidence interval , 0.84 to 1.21 ) . The latency period medians and interquartile ranges were similar between the two groups [ indomethacin 193 ( 92 to 376.5 ) hours versus placebo 199 ( 77.5 to 459 ) hours , P = 0.91 ] , and no differences were noted in any maternal or neonatal secondary outcomes . This limited study demonstrates no benefit with the use of prophylactic indomethacin tocolysis for women with PPROM OBJECTIVES To compare the efficacy and safety of nifedipine and ritodrine in preventing preterm labor , and to evaluate maternal side effects and neonatal outcome . STUDY DESIGN Non-blind , r and omized controlled trial RESULTS A r and omized trial of 102 pregnant women with gestational ages under 34 weeks , including 24 with twin pregnancies and 45 on betasympathicomimetic drugs , who had regular uterine contractions with either observed cervical changes or preterm rupture of membranes . After stratification women were r and omly assigned to receive either ritodrine intravenously or nifedipine orally . Fifty-five women were r and omized to the  nifedipine group and 47 to the  ritodrine  group . As expected , both groups were comparable in terms of several entry variables , including mean gestational age , ruptured membranes , treatment with tocolytic drugs , cervical examination , contraction frequency , age , and twin gestation . Delivery of women in the nifedipine group was delayed for 48 h , 7 days , and until 34 weeks gestation in 33 ( 60 % ) , 26 ( 47 % ) and 21(38 % ) cases , respectively , compared with 31 ( 66 % ) , 21(45 % ) and 11(23 % ) women in the ritodrine group ( no significant difference ) . Maternal side effects were significantly less common in the nifedipine group than in the ritodrine group , however after 7 days of therapy there was no difference between the two groups . Neonatal outcome was similar in the two groups , with four neonatal deaths in the nifedipine and five in the ritodrine group . CONCLUSIONS Nifedipine seems to be as effective as ritodrine in the treatment of preterm labor and is associated with less frequent side effects The purpose of the study was to determine if the adjunctive administration of magnesium sulfate with ritodrine would result in decreased dosage requirements of ritodrine , and , therefore , decrease the incidence of ritodrine-associated side effects . C and i date s for tocolysis were prospect ively r and omized so that some received a uniform tocolytic dose of magnesium sulfate in a blinded protocol . All patients received a ritodrine infusion which was titrated in the st and ard manner to achieve cessation of labor . Evaluations included interval cumulative ritodrine dose , maximal ritodrine infusion rate , fluid balance , and blood chemistry studies . Contrary to our hypothesis , there were significantly more cardiovascular effects in the group that received  ritodrine plus magnesium sulfate ( 11/24 ) than in the group that received ritodrine alone ( 1/17 ) ( p less than or equal to 0.02 ) . The predominant side effect was chest pain , frequently associated with electrocardiogram changes indicative of myocardial ischemia . These results are consistent with the current underst and ing of the regulatory mechanisms of these tocolytic agents . We conclude from the results of our prospect i ve , r and omized , blinded study that the adjunctive use of magnesium sulfate with ritodrine is associated with an unacceptable increase in serious side effects and probably does not improve efficacy The purpose of this r and omized , prospect i ve study was to evaluate the efficacy of tocolytic and antibiotic therapy in the  prolongation of pregnancy and neonatal outcome  in the treatment of premature rupture of the membranes without clinical labor .  Delivery was delayed for 48 h , 7 days and beyond 35 weeks of gestation in 87 , 39 and 18 % , respectively , of patients in the treated group ( n = 39 ) compared with 50 , 12 and 17 % of patients in the nontreated group ( n = 42 ) . The incidence of a low Apgar score ( < 7 at 5 min ) , requiring artificial ventilation , and infectious morbidity was more common in the treated group than in the nontreated group ( 18 vs. 0 , 41 vs. 17 and 39 vs. 17 % , respectively ) . There was no significant cost difference in survivors between the treated and nontreated groups , although the mothers in the treated group were significantly more expensive . From these observations , it appears that tocolysis and antibiotics are not effective in PROM cases OBJECTIVE To perform a comparison between atosiban ( oxytocin antagonist ) and nifedipin ( calcium channel blocker ) for acute treatment of preterm labor and their maternal safety . METHODS A r and omized controlled trial study was performed on 80 pregnant women with preterm labor , between 26 and 34 weeks of pregnancy , in Akbar Abadi Teaching Hospital in Tehran , Iran . 40 women ( the atosiban group ) were compared with another 40 women ( the nifedipin group ) for the drugs ' efficacy in delaying delivery for more than 48 h in order to undergo steroid therapy , and for more than 7 days or more , and also to assess their maternal safety . The duration between the drugs ' administration and delivery were compared . The statistical analysis was performed using the Statistical Package for Social Science ( SPSS ) . RESULTS There was no statistically significant difference between the two groups in the treatment of preterm labor .  Atosiban was effective in 82.5 % of cases , and nifedipin in 75 % of the cases ( p=1.000 ) , for delaying delivery for 48 h. Atosiban was effective in 75 % of the cases , and nifedipin in 65 % of the cases , for delaying delivery for more than 7 days . The maternal side effects in the atosiban group were 17.5 % , and in the nifedipin group they were 40 % , which had a statistically significant difference ( p=0.027 ) . The duration between treatment and delivery was 29.03+/-16.12 days in the atosiban group and 22.85+/-13.9 days in the nifedipin group with no statistically significant difference ( p=0.79 ) . CONCLUSION Atosiban is an effective and safe drug for the acute treatment of preterm labor with minimal side effects , and it can be an option in the treatment of preterm labor , especially in patients with heart disease and multi-fetal pregnancies Twenty-nine women with premature labor were r and omly assigned to a ritodrine ( N = 14 ) or placebo ( N = 15 ) drug group . The 2 groups were of similar age , parity , weight , gestational age , and cervical change at the onset of treatment . They were treated sequentially with intravenous , intramuscular , and oral drugs and monitored carefully during therapy . There was a significant increase in both the maternal and fetal heart rates during ritodrine treatment , and also a significant decrease in maternal blood pressure .  Ritodrine-treated women often complained of palpatations . There was no significant difference in the extension of pregnancy , birth weight , or infant survival for the ritodrine group . Although the 1-minute Apgar scores in the ritodrine group were higher , the 5-minute scores were similar in both groups OBJECTIVE This study was undertaken to assess the effectiveness of glyceryl trinitrate ( GTN ) patches in comparison with beta2 sympathomimetics ( beta2 ) for the treatment of  preterm labor .  STUDY DESIGN A multicenter , multinational , r and omized controlled trial was conducted in tertiary referral teaching hospitals . Women in threatened preterm labor with positive fetal fibronectin or ruptured membranes between 24 and 35 weeks ' gestation were recruited and r and omly assigned to either beta2 or GTN with rescue beta2 tocolysis if moderate-to-strong contractions persisted at 2 hours . Obstetric and neonatal outcomes were assessed . RESULTS Two hundred thirty-eight women were recruited and r and omly assigned , 117 to beta2 and 121 to GTN . On a strict intention-to-treat basis , there was no significant difference in the time to delivery using Kaplan-Meier curves ( P = .451 ) . At 2 hours , 27 % of women receiving beta2 had moderate or stronger contractions compared with 53 % in the GTN group ( P < .001 ) . This led to 35 % of women in the GTN group receiving rescue treatment . If delivery or requirement for beta2 rescue are regarded as treatment failure , then a significant difference was observed between the 2 arms ( P = .0032 ) . There were no significant differences in neonatal outcomes . CONCLUSION GTN is a less efficacious tocolytic compared with ss2 sympathomimetics Abstract Objective : To compare the efficacy of atosiban with usual management of  threatened preterm labor .  Methods : In this prospect i ve , open-label , r and omized controlled trial , women admitted to the hospital in threatened preterm labor ( between 24 and 34 weeks ' gestation ) were r and omized to receive atosiban or usual care ( β-agonists , calcium channel blockers , magnesium sulphate , or any other tocolytic , alone or in combination , and /or bed rest ) . Results : In women r and omized to receive atosiban ( n=295 ) or usual care ( n=290 ) , significantly more women receiving atosiban remained undelivered at 48 h with no alternative tocolytic compared with usual care ( 77.6 % vs. 56.6 % ; P<0.001 ) . The proportion of women remaining undelivered after 48 h was comparable between the treatment groups . However , more women in the atosiban group required no additional tocolytics ( 85.1 % vs. 62.8 % ; P<0.001 ) . Maternal and fetal safety was significantly superior with atosiban  . Neonatal safety was comparable . Conclusions : These findings support the use of atosiban to delay preterm birth and are consistent with previously conducted , r and omized , controlled trials . Atosiban was associated with fewer maternal and fetal adverse events compared with other tocolytics , and presented no safety concerns for either the mother or the unborn baby Objective To compare a new loading dose regimen for intravenous ritodrine administration in preterm labour with the conventional dose regimen One hundred women in preterm labor were r and omly treated with ritodrine or terbutaline in a double-blind fashion . The drugs were comparably effective during intravenous therapy but , in women with intact membranes , an oral dose of terbutaline , 30 mg daily , was significantly more effective than ritodrine , 120 mg daily , in preventing recurrent labor during a 5-day course of oral therapy ( one of 19 versus 12 of 23 , p less than 0.001 ) . In women with intact membranes , pregnancy was prolonged 40 + /- 25 days ( mean + /- SD ) in women receiving terbutaline orally and only 22 + /- 24 days in women receiving ritodrine orally ( p less than 0.01 ) . In women with intact membranes , a heart rate greater than or equal to 130 bpm occurred in in a higher proportion of women receiving intravenous treatment with ritodrine than among those receiving terbutaline ( 20 of 31 versus 8 of 27 , p less than 0.05 ) . Terbutaline-treated women , however , were significantly more likely to have a serum glucose level in excess of 140 mg/dl than were women treated with ritodrine ( 13 of 26 versus 6 of 29 , p less than 0.05 ) . Side effects commonly observed during intravenous therapy included nausea ( 22 % ) , chest pain ( 15 % ) , and shortness of breath ( 15 % ) . Side effects were significantly ( p less than 0.025 ) more likely to occur during periods when the infusion rate was being increased rather than during periods when the infusion rate was constant We conducted a r and omized trial comparing bed rest with tocolysis to determine the therapeutic efficacy , safety , and cost 
    Output:
    
Prophylactic tocolysis with PPROM was associated with increased overall latency , without additional benefits for maternal/neonatal outcomes .
For women with PPROM before 34 weeks , there was a significantly increased risk of chorioamnionitis in women who received tocolysis .
However , neonatal outcomes were not significantly different .
There were no significant differences in maternal/neonatal outcomes in subgroup analyses comparing cox inhibitor versus no tocolysis , calcium channel blocker versus betamimetic , antibiotic , corticosteroid or combined antibiotic/corticosteroid .
AUTHORS ' CONCLUSIONS Our review suggests there is insufficient evidence to support tocolytic therapy for women with PPROM , as there was an increase in maternal chorioamnionitis without significant benefits to the infant .