***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Eleven randomized controlled trials with a total of 833 women were included in this review. However, the results of this review are based on single studies with small numbers of participants.The majority of included studies reported insufficient information on sequence generation, allocation concealment as well as blinding. There were no included studies that assessed PTL or PTB as the primary outcome. The included studies were different in terms of intervention, practice, and time, and there were no clear coherent hypotheses. For women not in PTL, the benefits of relaxation was found in one study for maternal stress (Anxiety Stress Scale) at 26 to 29 weeks gestational age (mean difference (MD) -7.04; 95% confidence interval (CI) -13.91 to -0.17). In addition, there were some beneficial effects of relaxation including baby birthweight (MD 285.00 g; 95% CI 76.94 to 493.06); type of delivery; (vaginal delivery; risk ratio (RR) 1.52; 95% CI 1.13 to 2.04), (cesarean section; RR 0.38; 95% CI 0.19 to 0.78); maternal anxiety (MD -15.79; 95% CI -18.33 to -13.25); and stress (MD -13.08; 95% CI -15.29 to -10.87) when applying relaxation therapy together with standard treatment.   For women in PTL, the results for the main outcome of PTB in the intervention and control groups from a single study were not different (RR 0.95; 95% CI 0.57 to 1.59). The MD of birthweight in grams from the fixed-effect model from two included studies was MD -5.68; (95% CI -174.09 to 162.74). According to the results of this review, there is some evidence that relaxation during pregnancy reduces stress and anxiety. However, there was no effect on PTL/PTB. These results should be interpreted with caution as they were drawn from included studies with limited quality.
Output:

We searched the medical literature for the information from clinical studies and found 11 randomized controlled studies that met our inclusion criteria. We included 11 studies randomising a total of 833 women, although nearly all the results we report are based on single studies with small numbers of participants. We were unable to pool the findings in any meta-analyses due to each study using different forms of relaxation in different comparisons, to prevent preterm births in seven studies and to treat preterm labour in five with insufficient information. No valid conclusion can be summarized from this review. For women not in preterm labour, relaxation therapy (alone or combined with standard treatment) reduced maternal stress compared with routine prenatal care and increased birthweight with fewer cesarean deliveries in a single study. For women in preterm labour, there was no evidence of benefits or harms. More rigorous studies are required in order to assess the effects of relaxation therapies in preventing and treating preterm labour.