***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: Eighteen RCTs were included in the review, of which 14 were included in the meta-analyses (in total 2279 couples). The evidence was current to October 2013. The quality of the evidence was low or very low for most comparisons . The main limitations in the evidence were failure to describe study methods, serious imprecision and attrition bias. Ten RCTs compared different methods of timing for IUI. We found no evidence of a difference in live birth rates between hCG injection versus LH surge (odds ratio (OR) 1.0, 95% confidence interval (CI) 0.06 to 18, 1 RCT, 24 women, very low quality evidence), urinary hCG versus recombinant hCG (OR 1.17, 95% CI 0.68 to 2.03, 1 RCT, 284 women, low quality evidence) or hCG versus GnRH agonist (OR 1.04, 95% CI 0.42 to 2.6, 3 RCTS, 104 women, I2 = 0%, low quality evidence). Two RCTs compared the optimum time interval from hCG injection to IUI, comparing different time frames that ranged from 24 hours to 48 hours. Only one of these studies reported live birth rates, and found no difference between the groups (OR 0.52, 95% CI 0.27 to 1.00, 1 RCT, 204 couples). One study compared early versus late hCG administration and one study compared different dosages of hCG, but neither reported the primary outcome of live birth. We found no evidence of a difference between any of the groups in rates of pregnancy or adverse events (multiple pregnancy, miscarriage, ovarian hyperstimulation syndrome (OHSS)). However, most of these data were very low quality. There is insufficient evidence to determine whether there is any difference in safety and effectiveness between different methods of synchronization of ovulation and insemination. More research is needed.
Output:

We found 18 randomised controlled trials, all comparing different timing methods in one treatment cycle for IUI, with a total of 2279 couples. The evidence was current to October 2013. We found no evidence of a difference in live birth rates between timing methods. We also found no evidence of a difference between any of the groups in rates of pregnancy or adverse events (multiple pregnancy, miscarriage, ovarian hyperstimulation syndrome (OHSS)). Most of the evidence was of low or very low quality. The main limitations were poor reporting of study methods, imprecision and losses to follow up. More research is needed.