Reviewer ’s report  
 
Title:  Association of Endogenous Progesterone Levels in Young Women Using Hormonal 
Contraception with Recent HIV -1 Infection  
 
Version: 1 Date: 01 Nov 2018 
 
Reviewer:  Leslie  Meyn  
 
Reviewer’s report:  
 
This was a retrospective analysis of a subset of samples from a large multicenter trial that 
evaluated the safety and efficacy of a vaginal microbicide gel. The objective of this sub -analysis 
was to evaluate the association of endogenous progesterone level s in women who were not using 
hormonal contraception and those using DMPA and Net -En with recent acquisition of HIV 
infection. This study was likely underpowered to find significant associations, which the authors 
acknowledged, but does investigate a possi ble mechanism by which DMPA use may contribute 
to increased susceptibility to HIV infection.  
 
 
I have a few minor comments:  
 
1. In the methods, '3 monthly intervals' is confusing. It could be interpreted as being sampled at 3 
1-month intervals or at 3 -mont h intervals. I would suggest changing the wording to tested at 3 -
month intervals for clarity.  
 
2. Please include the length of follow -up for the women included in this study.  
 
3. Provide the median time to first HIV -positive sample for the sero -converters and median 
length of follow -up for those that remain sero -negative.  
 
4. Provide the breakdown of women who were randomized to use the placebo gel and the active 
microbicide  gel. Did the active gel impact HIV acquisition in the parent study? Was there a 
difference in serum progesterone levels between active and placebo among sero -converters and 
sero-negative women or those using HC and not using HC? An association between end ogenous 
progesterone level and sero -conversion may have been masked by microbicide gel use.  
 
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.  
 
Yes 
 
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 stati stics 
 
Quality of written English  
Please indicate the quality of language in the manuscript:  
 
Acceptable  
 
Declaration of competing interests  
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