Reviewer ’s report  
 
Title: A preliminary evaluation of influence of body mass index on in vitro fertilization outcome  
in non -obese endometriosis patients. An observational cross -sectional study  
 
Version: 0 Date: 30 Mar 2017  
 
Reviewer: Edgar do Somigliana  
 
Reviewer's report:  
 
In this retrospective cohort study, Garalejic et al investigated the potential impact of BMI on IVF 
success rate in non -obese women with endometriosis. The chance of pregnancy was not 
influenced by the BMI category (under -weight / normal weight / over -weight). The rational for 
the investigation is weak and, most importantly, the sample size (16+111+29) is absolutely 
insufficient to draw meaningful conclusions.  
 
Minor comments  
The Materials and methods section is too long. It can be halved without losing relevant 
information. In contrast, a sample size calculation is lacking and should be added.  
The discussion is also exceedingly long. Surprisingly, the authors dedicate most of the discussion 
to discuss their results within the available literature but only few lines to the important 
limitations of their paper.  
 
 
Are the methods appropriate and well described?  
If no t, please specify what is required in your comments to the authors.  
 
No 
Does the work include the necessary controls?  
If not, please specify which controls are required in your comments to the authors.  
 
No 
 
Are the conclusions drawn adequately supported by t he data shown?  
If not, please explain in your comments to the authors.  
 
No 
Are you able to assess any statistics in the manuscript or would you recommend an  
additional statistical review?  
If an additional statistical review is recommended, ple ase specify what aspects require further  
assessment in your comments to the editors.  
 
I am able to assess the statistics  
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
 
 
 
Declaration of competing interests  
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holds  or has applied for patents relating to the content of the manuscript?  
 
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below.  If your reply is yes to any, please g ive details below.  
 
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