***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 The efficacy and safety of repeat doses of prenatal corticosteroids remains uncertain . Our aim was to establish whether repeat prenatal corticosteroids given to women at risk of preterm birth can reduce neonatal morbidity without harm . METHODS In this hospital-based study , 982 women who remained at risk of preterm birth at less than 32 weeks ' gestation , 7 or more days after receiving a first course of prenatal corticosteroids  , were r and omly assigned to receive a repeat intramuscular dose of either 11.4 mg betamethasone ( as Celestone Chronodose ) , or saline placebo . This was repeated every week the woman remained undelivered , at less than 32 weeks ' gestation , and at risk of preterm birth . Primary outcomes were occurrence and severity of neonatal respiratory distress syndrome , use and duration of oxygen and mechanical ventilation , and weight , length , and head circumference at birth and hospital discharge . Statistical analyses were on an intention to treat basis . This study is registered as an International St and ard R and omised Controlled Trial , number IS RCT N48656428 . FINDINGS Fewer babies exposed to repeat corticosteroids had respiratory distress syndrome ( 33%vs 41 % ; relative risk 0.82 , 95 % CI 0.71 - 0.95 , p=0.01 ) and fewer had severe lung disease ( 12%vs 20 % ; relative risk 0.60 , 95 % CI 0.46 - 0.79 , p=0.0003 ) than those in the placebo group . In keeping with these benefits , babies exposed to repeat corticosteroids needed less oxygen therapy ( p=0.03 ) , and shorter duration of mechanical ventilation ( p=0.01 ) . Mean weight , length , and head circumference at birth and hospital discharge did not differ between treatment groups . Z-scores for weight ( p=0.04 ) and head circumference ( p=0.03 ) at birth were lower in the babies who received repeat corticosteroids although at the time of hospital discharge Z-scores did not differ between treatment groups ( p=0.29 for weight , p=0.48 for head circumference ) . INTERPRETATION Exposure to repeat doses of antenatal corticosteroids reduces neonatal morbidity . Pending long-term outcome results , the short-term benefits for the babies in our study support the use of repeat doses of corticosteroids in women who remain at risk of very preterm birth 7 or more days after an initial course Background The Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study ( MACS ) showed no benefit in the reduction of major neonatal mortality/morbidity or neurodevelopment at 2 and 5 years of age . Using the data from the r and omized controlled trial and its follow-up , the aim of this study was to evaluate the association between gestational ages at birth in children exposed to single versus multiple courses of antenatal corticosteroid ( ACS ) therapy  in utero and outcomes at 5 years of age . Method A total of 1719 children , with the breakdown into groupings of < 30 , 30–36 , and ≥ 37 weeks gestation at birth , contributed to the primary outcome : death or survival with a disability in one of the following domains : neuromotor , neurosensory , and neurobehavioral/emotional disability and were included in this analysis . Results Gestational age at birth was strongly associated with the primary outcome , p < 0.001 . Overall , the interaction between ACS groups and gestational age at birth was not significant , p = 0.064 . Specifically , in the 2 preterm categories , there was no difference in the primary outcome between single vs. multiple ACS therapy . However , for infants born ≥37 weeks gestation , there was a statistically significant increase in the risk of the primary outcome  in multiple ACS therapy , 48/213 ( 22.5 % ) compared to 38/249 ( 15.3 % ) in the single ACS therapy ; OR = 1.69 [ 95 % CI : 1.04 , 2.77 ] ; p = 0.037 . Conclusion Preterm birth ( < 37 weeks gestation ) remained the primary factor contributing to an adverse outcome regardless of the number of courses of ACS therapy . Children born ≥ 37 weeks and exposed to multiple ACS therapy may have an increased risk of neurodevelopmental/neurosensory impairment by 5 years of age . To optimize outcomes for infants/children , efforts in reducing the incidence of preterm birth should remain the primary focus in perinatal research .Trial registration This study has been registered at ( identifier NCT00187382 Maternal administration of corticosteroids is used to promote lung maturation in human infants considered at risk of preterm delivery [ 1 ] . R and omised trials of a single course of corticosteroid treatment have indicated no adverse long-term neurological or cognitive sequelae [ 2 - 5 ] . However , the current trend in many obstetric centres is to use repeated courses in cases where preterm birth has not eventuated , but the risk persists 7 days beyond administration of the original course [ 6 - 7 ] . This practice has not yet been subject to r and omised trials of outcome . We have examined the effect of repeated injections of corticosteroids on the development of the optic nerve in prenatal fetal sheep and report a significant delay in the myelination of optic axons . Our results , together with those from other animal studies [ 8 ] , show that repeated courses of corticosteroids may be detrimental to central nervous system ( CNS ) development . Clinical practice should balance the known beneficial effects on lung maturation of a single course of corticosteroid against the potential damage to the CNS of repeated courses Our objective was to assess the effects of repeated antenatal corticosteroid treatments on the neonatal auditory brainstem response ( ABR ) , a sensitive measure of neonatal brain maturity and auditory function . To achieve this , we performed and blindly evaluated neonatal ABRs on a subset of infants delivering within a multicenter r and omized  placebo-controlled clinical trial comparing single versus repeated courses of antenatal corticosteroid treatments  for women at 23 - 31 weeks gestation who remained at increased risk for preterm birth . The women were r and omly assigned to either the single or the repeated antenatal corticosteroid treatment group . Women in the repeated antenatal corticosteroid group received weekly antenatal corticosteroid treatments until 34 weeks gestation or until they reached a study -determined limited number of courses , whereas women in the single antenatal corticosteroid group received an initial course of corticosteroid followed by weekly placebo injections . We performed ABR testing on their infants prior to discharge . The latencies of waves I , III and V and the peak-to-trough amplitudes of waves I and V were compared between those in the single ( n=27 ) and repeated antenatal corticosteroid treatment ( n=24 ) groups . The majority of repeated antenatal corticosteroid infants ( 20 of 24 ) were exposed to ≥ 4 antenatal corticosteroid treatments . Even though gestational age was similar between our subset of single and repeated antenatal corticosteroid treatment groups , infant birth weight and length and head circumference were significantly smaller in the repeated antenatal corticosteroid group ( p < 0.05 ) . Despite these differences in birth sizes , there were no significant group differences in the ABR wave latencies or amplitudes . We concluded that our repeated antenatal corticosteroid treatments , in comparison to a single treatment , did not significantly benefit or harm the neonatal ABR despite significant effects on birth size BACKGROUND : Treatment of women at risk for preterm birth with repeat doses of glucocorticoids reduces neonatal morbidity but could have adverse long-term effects on cardiometabolic health in offspring . We assessed whether exposure to repeat antenatal betamethasone increased risk factors for later cardiometabolic disease  in children whose mothers participated in the Australasian Collaborative Trial of Repeat Doses of Corticosteroids . METHODS : Women were r and omized to betamethasone or placebo treatment , ≥7 days after an initial course of glucocorticoids , repeated each week that they remained at risk for preterm birth at < 32 weeks ’ gestation . In this follow-up study , children were assessed at 6 to 8 years ’ corrected age for body composition , insulin sensitivity , ambulatory blood pressure , and renal function . RESULTS : Of 320 eligible childhood survivors , 258 were studied ( 81 % ; 123 repeat betamethasone group ; 135 placebo [ single course ] group ) . Children exposed to repeat antenatal betamethasone and those exposed to placebo had similar total fat mass ( geometric mean ratio 0.98 , 95 % confidence interval [ CI ] 0.78 to 1.23 ) , minimal model insulin sensitivity ( geometric mean ratio 0.89 , 95 % CI 0.74 to 1.08 ) , 24-hour ambulatory blood pressure ( mean difference systolic 0 mm Hg , 95 % CI −2 to 2 ; diastolic 0 mm Hg , 95 % CI −1 to 1 ) , and estimated glomerular filtration rate ( mean difference 1.2 mL/min/1.73m2 , 95 % CI −3.2 to 5.6 ) . CONCLUSIONS : Exposure to repeat doses of antenatal betamethasone compared with a single course of glucocorticoids does not increase risk factors for cardiometabolic disease at early school age OBJECTIVE : This study was performed to evaluate the efficacy of weekly courses of antenatal corticosteroids compared with a single course in women with preterm premature rupture of membranes ( PROM ) . METHODS : A planned secondary analysis of women with preterm PROM who participated in a multicenter , r and omized trial of weekly courses of antenatal corticosteroids versus  single-course therapy  was performed . After their first course of st and ard antenatal steroid therapy , administered between 24 to 32–6/7 weeks of gestation , consenting women were r and omly assigned to receive betamethasone versus placebo injections weekly until 34–0/7 weeks of gestation . Maternal and neonatal morbidities were compared between the 2 groups . RESULTS : Of the 161 women with preterm PROM , 81 women were assigned to receive weekly courses of steroids and 80 to the single-course group . There were no significant differences in composite morbidity between the groups ( 27 [ 34.2 % ] of 81 patients versus 33 [ 41.8 % ] of 80 patients , P = .41 ) . Chorioamnionitis was higher in patients who received weekly courses of antenatal steroids ( 39 [ 49.4 % ] of 81 patients versus 25 [ 31.7 % ] of 80 patients , P = .04 ) . CONCLUSION : Weekly courses of antenatal steroids in women with preterm PROM did not improve neonatal outcomes beyond that achieved with single-course therapy and was associated with an increased risk of chorioamnionitis .  Antenatal steroid therapy should not be routinely repeated in patients with preterm PROM . LEVEL OF EVIDENCE : Background : Preterm labor is the most common complication of the pregnancy in the second trimester and has been suggested as the cause of two-thirds of neonatal mortality . Antenatal corticosteroid is used for fetal lung maturity in preterm labor and makes a significant reduction in the incidence of respiratory distress syndrome ( RDS ) . The aim of this study was to compare the prenatal administration of single and multiple courses of betamethasone and neonatal outcomes , effectiveness and safety of its weekly administration . Material s and Methods : A r and omized , double-blind placebo-control clinical trial study conducted in pregnant women at risk for preterm birth by gestational age between 28 and 35 weeks . The women received a course of betamethasone at first , and then divided into a single course and multiple betamethasone courses . They evaluated for the incidence of RDS , need for oxygen , surfactant administration , the need for ventilation , duration of hospitalization and neonatal mortality . Data were analyzed using SPSS-version 16 and Chi-square test and t-test . Results : The need for O2 , the incidence of RDS , the need for hospitalization , days of hospitalization , the need for continuous positive airway pressure , ventilation and surfactant and the mortality significantly lower in the multiple course groups and betamethasone had a clear positive effect in this regard . Mean weight , height and head circumferences were significantly lower in the multiple course group . Conclusion : Despite a positive impact of multiple betamethasone usage on mortality and morbidity in neonates , it is recommended to avoid routinely using of betamethasone multiple courses until the adequate data of studies prove the safety of reduction in weight , height , and head circumference in a long period Background : The airway epithelial sodium channel ( ENaC ) is rate limiting for postnatal alveolar fluid clearance . Increased lung water content is a feature of respiratory distress syndrome ( RDS ) , which is reduced by antenatal corticosteroid treatment in preterm infants . Objectives : Since corticosteroids also induce ENaC gene expression , we studied whether a repeat dose of antenatal β-methasone affects postnatal expression of airway ENaC. Methods : 17 pregnant women with imminent preterm birth were r and omized to receive a single repeat dose of β-methasone ( 12 mg ) or placebo ( repeat β-methasone : 8 infants , gestational age ( GA ) 30.8 ± 2.2 weeks ; placebo : 14 infants , GA  
    Output:
    
At early childhood follow-up , no statistically significant differences were seen for infants exposed to repeat prenatal corticosteroids compared with unexposed infants for the primary outcomes ( total deaths ; survival free of any disability or major disability ; disability ; or serious outcome ) or in the secondary outcome growth assessment s. In women , for the two primary outcomes , there was no increase in infectious morbidity of chorioamnionitis or puerperal sepsis , and the likelihood of a caesarean birth was unchanged .
The short-term benefits for babies of less respiratory distress and fewer serious health problems in the first few weeks after birth support the use of repeat dose(s ) of prenatal corticosteroids for women still at risk of preterm  birth seven days or more after an initial course .
These benefits were associated with a small reduction in size at birth .
The current available evidence reassuringly shows no significant harm in early childhood , although no benefit .