***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: We compared neonatal outcomes in twin pregnancies following moderately preterm birth ( MPTB ) , late preterm birth ( LPTB ) , and term birth . A secondary analysis of a multicenter , r and omized controlled trial of multiple gestations was conducted . MPTB was defined as delivery between 32 (0)/(7 ) and 33 (6)/(7 ) weeks and LPTB between 34 (0)/(7 ) and 36 (6)/(7 ) weeks . Primary outcome was a neonatal outcome composite consisting of one or more of the following : neonatal death , respiratory distress syndrome , early onset culture-proven sepsis , stage 2 or 3 necrotizing enterocolitis , bronchopulmonary dysplasia , grade 3 or 4 intraventricular hemorrhage , periventricular leukomalacia , pneumonia , or severe retinopathy of prematurity . Among 552 twin pregnancies , the MPTB rate was 14.5 % , LPTB 49.8 % , and term birth rate 35.7 % . The rate of the primary outcome was different between groups : 30.0 % for MPTB , 12.8 % for LPTB , 0.5 % for term birth ( P < 0.001 ) . Compared with term neonates , the primary neonatal outcome composite was increased following MPTB ( relative risk [ RR ] 58.5 ; 95 % confidence interval [ CI ] 11.3 to 1693.0 ) and LPTB ( RR 24.9 ; 95 % CI 4.8 to 732.2 ) . Twin pregnancies born moderately and late preterm encounter higher rates of neonatal morbidities compared with twins born at term OBJECTIVES To determine whether progesterone supplementation alters cervical shortening in women at increased risk for preterm birth . METHODS We performed a planned secondary analysis from a large , multinational preterm birth prevention trial of daily intravaginal progesterone gel , 90 mg , compared with placebo in women with a history of spontaneous preterm birth or premature cervical shortening .  Transvaginal cervical length measurements were obtained in all r and omized patients at baseline ( 18 + 0 to 22 + 6 weeks ' gestation ) and at 28 weeks ' gestation . For this secondary analysis , the difference in cervical length between these time points was compared for the study population with a history of spontaneous preterm birth and for a population with premature cervical shortening ( < or = 30 mm ) at r and omization . Differences between groups in cervical length for the 28-week examination were analyzed using ANCOVA , including adjustment for relevant clinical parameters and maternal characteristics . RESULTS Data were analyzed from 547 r and omized patients with a history of preterm birth . The progesterone-treated patients had significantly less cervical shortening than the placebo group ( difference 1.6 ( 95 % CI , 0.3 - 3.0 ) mm ; P = 0.02 , ANCOVA ) . In the population of 104 subjects with premature cervical shortening at r and omization , the cervical length also differed significantly on multivariable analysis , with the treatment group preserving more cervical length than the placebo group ( difference 3.3 ( 95 % CI , 0.3 - 6.2 ) mm ; P = 0.03 , ANCOVA ) , with adjustment for differences in cervical length at screening . A significant difference was also observed between groups for categorical outcomes including the frequency of cervical length progression to < or = 25 mm and a > or = 50 % reduction in cervical length from baseline in this sub population . CONCLUSIONS Intravaginal progesterone enhances preservation of cervical length in women at high risk for preterm birth BACKGROUND Midtrimester amniocentesis to investigate fetal karyotype carries a small risk of fetal loss . AIM To test the hypothesis that progesterone prophylaxis may reduce this . STUDY DESIGN A r and omised controlled trial comparing a short prophylactic treatment with progesterone after amniocentesis with untreated controls . RESULTS There were no differences in frequency of miscarriage , preterm delivery or neonatal outcome . CONCLUSION Prophylactic progesterone treatment after amniocentesis does not improve obstetric outcome OBJECTIVE : A multicenter , r and omized placebo-controlled trial among women with singleton pregnancies and a history of spontaneous preterm birth found that weekly injections of 17 alpha-hydroxyprogesterone caproate ( 17P ) , initiated between 16 and 20 weeks of gestation , reduced preterm birth by 33 % . The current study estimated both preterm birth recurrence and the potential reduction in the national preterm birth rate . METHODS : Using 2002 national birth certificate data , augmented by vital statistics from 2 states , we estimated the number of singleton births delivered to women eligible for 17P through both a history of spontaneous preterm birth and prenatal care onset within the first 4 months of pregnancy . The number and rate of recurrent spontaneous preterm births were estimated . To predict effect , the reported 33 % reduction in spontaneous preterm birth attributed to 17P therapy was applied to these estimates . RESULTS : In 2002 , approximately 30,000 recurrent preterm births occurred to women eligible for 17P , having had a recurrent preterm birth rate of 22.5 % . If 17P therapy were delivered to these women , nearly 10,000 spontaneous preterm births would have been prevented , thereby reducing the overall United States preterm birth rate by approximately 2 % , from 12.1 % to 11.8 % ( P < .001 ) , with higher reductions in targeted groups of eligible pregnant women . CONCLUSION : Use of 17P could reduce preterm birth  among eligible women , but would likely have a modest effect on the national preterm birth rate . Additional research is urgently needed to identify other population s who might benefit from 17P , evaluate new methods for early detection of women at risk , and develop additional prevention strategies . LEVEL OF EVIDENCE : Background 15 % of multiple pregnancies ends in a preterm delivery , which can lead to mortality and severe long term neonatal morbidity . At present , no generally accepted strategy for the prevention of preterm birth in multiple pregnancies exists . Prophylactic administration of 17-alpha hydroxyprogesterone caproate ( 17OHPC ) has proven to be effective in the prevention of preterm birth in women with singleton pregnancies with a previous preterm delivery . At present , there are no data on the effectiveness of progesterone in the prevention of preterm birth in multiple pregnancies . Methods / Design We aim to investigate the hypothesis that 17OHPC will reduce the incidence of the composite neonatal morbidity of neonates by reducing the early preterm birth rate in multiple pregnancies . Women with a multiple pregnancy at a gestational age between 15 and 20 weeks of gestation will be entered in a placebo-controlled , double blinded r and omised study comparing weekly 250 mg 17OHPC intramuscular injections from 16–20 weeks up to 36 weeks of gestation versus placebo . At study entry , cervical length will be measured . The primary outcome is composite bad neonatal condition ( perinatal death or severe morbidity ) . Secondary outcome measures are time to delivery , preterm birth rate before 32 and 37 weeks , days of admission in neonatal intensive care unit , maternal morbidity , maternal admission days for preterm labour and costs . We need to include 660 women to indicate a reduction in bad neonatal outcome from 15 % to 8 % . Analysis will be by intention to treat . We will also analyse whether the treatment effect is dependent on cervical length . Discussion This trial will provide evidence as to whether or not 17OHPC-treatment is an effective means of preventing bad neonatal outcome due to preterm birth in multiple pregnancies . Trial registration Current Controlled Trials IS RCT Objective . To compare rates of preterm birth before 35 weeks based on cervical length measurement at 16–20 weeks in women with twin gestations who received 17-α hydroxyprogesterone caproate ( 17OHPC ) or placebo .  Methods . This is a secondary analysis of a r and omised , double-blind , placebo-controlled trial of twin gestations exposed to 17OHPC or placebo .  Baseline transvaginal ultrasound evaluation of cervical length was performed prior to treatment assignment at 16–20 weeks . Cervical length measurements were categorised according to the 10th , 25th , 50th and 75th percentiles in the women studied . The effect of 17OHPC  administration in women with a short ( 25th percentile  )  and long ( 75th percentile ) cervix was evaluated . Results . Of 661 twin gestations studied , 221 ( 33.4 % ) women enrolled at 11 centers  underwent cervical length measurement . The 10th , 25th , 50th , 75th percentiles for cervical length at 16–20 weeks were 32 , 36 , 40 and 44 mm , respectively . The risk of preterm birth < 35 weeks was increased in women with a cervical length < 25th percentile ( 55.8 vs. 36.9 % , p = 0.02 ) . However , a cervical length > 75th percentile at this gestational age interval was not protective for preterm birth ( 36.5 vs. 42.9 % , p = 0.42 ) . Administration of 17OHPC did not reduce preterm birth before 35 weeks among those with either a short or a long cervix ( 64.3 vs. 45.8 % , p = 0.18 and 38.1 vs. 35.5 % , p = 0.85 , respectively ) . Conclusion . Women with twin gestations and a cervical length below the 25th percentile at 16–20 weeks had higher rates of preterm birth . In this subgroup of women , 17 OHPC did not prevent preterm birth before 35 weeks gestation . A cervical length above the 75th percentile at 16–20 weeks did not significantly reduce the risk of preterm birth in this high risk population Whilst only about a third of all cerebral palsy occurs in children who had been of low birthweight , recent increases in the survival of low and very low birthweight infants have coincided with significant increases in the numbers of cerebral palsy children amongst them . This paper analyses data from the Western Australian Cerebral Palsy Register and from the Maternal and Child Health Research Data Base for stillbirths , neonatal deaths and survivors to address the issues of increased survival , cerebral palsy and timing of brain damage . The analysis is inconclusive but suggestive that both antenatal and postnatal complications are important in the increases in cerebral palsy in low birthweight infants . The good news is that this means that a certain proportion of postnatally damaged low birthweight survivors could possibly be prevented by better neonatal care . The bad news is that the remaining proportion have probably received their damage well before delivery and the possibilities for prevention are still remote . Further studies of low birthweight infants with cerebral palsy are urgently required . They should include antenatal factors , investigating the various aetiological pathways to preterm birth , r and omised controlled trials of neonatal interventions and search ing for better neonatal predictors of brain damage The aim of this study was to evaluate the effect of vaginal natural progesterone on the prevention of preterm birth in IVF/intracytoplasmic sperm injection ( ICSI ) pregnancies . A single-centre prospect i ve placebo-controlled r and omized study was performed . A total of 313 IVF/ICSI pregnant patients were r and omized into two groups for either treatment with daily 400 mg vaginal natural progesterone or placebo , starting from mid-trimester up to 37 weeks or delivery . Amongst the patients , there were 215 singleton and 91 twin pregnancies . There was no significant difference in risk of preterm birth among all patients ( OR 0.672 , 95 % CI 0.42 - 1.0 . There was a significantly lower preterm birth rate in singleton pregnancies in the natural progesterone arm ( OR 0.53 , 95 % CI 0.28 - 0.97 ) and no significant difference between both arms in twin pregnancies ( OR 0.735 , 95 % CI 0.36 - 2 ) . In conclusion , the administration of 400 mg vaginal natural progesterone from mid trimester reduced the incidence of preterm birth in singleton , but not in twin , IVF/ICSI pregnancies Background Women with a short cervical length in mid-trimester pregnancy have a higher risk of preterm birth and therefore a higher rate of neonatal mortality and morbidity .  Progesterone can potentially decrease the number of preterm births and lower neonatal mortality and morbidity . Previous studies showed good results of progesterone in women with either a history of preterm birth or a short cervix . However , it is unknown whether screening for a short cervix and subsequent treatment in mid trimester pregnancy is effective in low risk women . Methods / Design We plan a combined screen and treat study among women with a singleton pregnancy without a previous preterm birth . In these women , we will measure cervical length at the st and ard anomaly scan performed between 18 and 22 weeks . Women with cervical length ≤ 30 mm at two independent measurements will be r and omly allocated to receive either vaginal progesterone 
    Output:
    
No differential effects in terms of route of administration , time of commencing therapy and dose of progesterone were observed for the majority of outcomes examined .
The use of progesterone is associated with benefits in infant health following administration in women considered to be at increased risk of preterm birth due either to a prior preterm birth or where a short cervix has been identified on ultrasound examination .