Reviewer’s report
Title: Hyaluronan-binding protein 2 (HABP2) gene variation in women with recurrent miscarriage
Version: 0 Date: 08 May 2017
Reviewer: Siim Sõber
Reviewer's report:
Hosseini Akram et al. report a case-control study comparing RM patients to healthy controls with  
respect to genotypes of three SNPs in HABP2 gene. The results of the analysis are that 1) women with  
at least 5 miscarriages are less likely to have a successful pregnancy compared to women with 3-4  
miscarriages 2) The SNPs are not associated with RM. Unfortunately the work in its current from is  
quite sloppy with major shortcomings.
The studied samples are not well described. The authors should provide a table describing all used  
samples and studied groups for key parameters including counts, age, BMI, follow-up time, numbers of  
successful and unsuccessful pregnancies and other available relevant parameters.
In the methods section the authors state "The follow-up time for calculation of pregnancy outcome was  
two years", in discussion the it is stated that "The weakness of the study is the varying follow-up time,  
although it is at least 2 years". Why is varying follow-up time a weakness if two years was used?
The results of the study are provided in eight lines of text, a table and a figure. The first paragraph of  
results and figure 1 pertain to the lower likelihood of women with more miscarriages to successfully  
deliver.  This  finding  is  not  particularly  novel,  it  is  in  fact  a  generally  accepted  rule  in  RM  
epidemiology. Additional data is of course always welcome, but this study provides very little at the  
moment. The authors should conduct a proper analysis of how the number of miscarriages affects  
pregnancy success  and  provide  counts  of  used  groups,  statistical  significance  of  differences  and  
confidence intervals. And discuss their findings in the context of previous knowledge. This paragraph  
contains conflicting information - is the overall probability for successful pregnancy 78.3% or 73.8%?
The results of SNP genotyping and association analysis are provided in Table 1. This table is confusing  
and should be reformatted. It appears to have two conflicting headings. It is not clear what numbers are  
provided, chi-squared values or p values. There is no need to provide raw chi-squared values. Please  
provide only p values and make it clear what the value is referring to.
Minor comments:
Figure 1 legend is broken
page 10 line 46 - "confirming previous studies" - please cite the previous studies.
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
Yes
Does the work include the necessary controls?
If not, please specify which controls are required in your comments to the authors.
Yes
Are the conclusions drawn adequately supported by the 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, please 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:
Needs some language corrections before being published
Declaration of competing interests
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