Reviewer’ s report
Title: Stool frequency and form and gastrointestinal symptoms differ by day of the menstrual
cycle in healthy adult women taking oral contraceptives: a prospective observational study
Version: 0Date: 20 Dec 2019
Reviewer: Andrea Rapkin
Reviewer's report:
The manuscript has improved significantly but still suffers from lack of focus and knowledge
regarding reproductive endocrinology and contraceptive technology. Perhaps including agynecologist as one of the authors may be helpful.The title and focus of the analysis was changedto address only women taking OCs and is therefore now more accurate. However, the introductionand discussion should be re written and to illuminate the mechanisms for symptoms with OCS orcompare to those not taking OCs. Using the words "menstrual cycle" is still misleading. Thediscussion of why pain, stress and GI symptoms are more prevalent on day 1 of menses is verysuperficial and the reference in the Intro is from the 80s. I suggest reading the Evans review oninflammation withy menstruation (Rev Endocr Metab Disord (2012) 13:277-288).In thegynecological literature since 2012, there many publications on the rationale for extended cycleOC regimens, and these papers documented higher symptom levels during menstruation even withOCs. This was neglected in the discussion and Intro. Significantly, increased stress on day 1 maybe due to pain, to GI symptoms, or unrelated. To further interpret the findings effectively, consideran analysis of stress while controlling for level of pain. Similarly, analysis can be performedcontrolling for GI symptoms or for both pain and GI symptoms. The concept of hormonewithdrawal vs menses may be of interest, and if the subjects listed their medication by name in the
study intake form, the authors should know if women were taking a 21-7 or 24 -4 regimen.
Regardless, with the first few days of placebo pills, one may see the symptoms related tohormone withdrawal whereas menstruation (day 1) generally begins after 2-3 days of placebo pillintake.
Are the methods appropriate and well described?
If not, please specify what is required in your comments to the authors.
YesDoes the work include the necessary controls?
If not, please specify which controls are required in your comments to the authors.
YesAre 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 furtherassessment in your comments to the editors.
I am able to assess the statisticsQuality of written English
Please indicate the quality of language in the manuscript:
Acceptable
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