PONE-D-25-16297Hormonal Contraceptives and Body Composition by Use of Stable Isotope Dilution Techniques Among Women of Reproductive Age in Nyeri County, KenyaPLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #4: I Don't Know

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3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The objective of the paper is relevant, grouping all hormonal and non-hormonal contraceptives in two different categories may obscure important differences between them, particularly in how each type may contribute to changes in body composition. It would be helpful to clearly specify and justify why the different types were combined into a single category.

Reviewer #2: This manuscript presents an important and timely study on the association between hormonal contraceptive use and body composition among women in Nyeri County, Kenya, using stable isotope dilution techniques. The topic is relevant and the methodology is scientifically sound.

However, please confirm that this work has not been published or submitted elsewhere to address any concerns about dual publication.

I am certain that this paper could be a valuable contribution to the field.

Reviewer #3: Overall, this is a good study; however, some improvements are needed. The authors provided all necessary details regarding ethical approval and funding.

- Can the author justify why in the abstract, the sample size is reported as 114, while in the methods section, it is stated as 119, and at the endline, it is 104. Additionally, a 3-month follow-up is mentioned in the abstract, but the assessment methodology refers to a 6-month follow-up.

Introduction:

- Overall, the introduction is good but too brief.

- It would be beneficial to elaborate more, such as providing an overview of non-hormonal contraceptives, including their worldwide prevalence and specific statistics for Kenya, would be helpful.

- - If available, data/ percentage of women using hormonal contraceptive in Kenya, as well as the most commonly used methods worldwide and within Kenya.

- - It would enhance the study’s purpose to elaborate on the selection of "Kamakwa Ward," linking body composition to non-communicable diseases, such as diabetes. Are cardiovascular diseases also involved? This connection would strengthen the public health rationale for the study.

- More detail about “Stable Isotope Dilution Techniques (SIDT)” and which studies have employed these methods would be beneficial.

- Mentioning the reproductive age of the women studied would help in conveying the results to a broader, non-scientific audience.

- Clarification is needed on what the authors mean by “modern contraceptive” and what constitutes an “un-modern contraceptive.”

Methods, Study Design, and Population:

- It is important to specify which data collection tool was used for greater precision.

Statistical Analysis:

- The authors mention that multivariate regression analysis was conducted; however, no figures are provided to illustrate this regression.

- Including figures or graphs would be more helpful for the reader to compare than solely using tables.

Discussion:

- The first two paragraphs of the discussion repeat the results. It would be more effective if the authors compared their findings to those of international studies, highlighting where they are similar or diverge.

Referencing:

- Ensure that the references are formatted uniquely; for instance, in the introduction, the first reference is listed as (United Nations, 2019), while subsequent references should follow a consistent format.

- Reconsider the referencing in the discussion. For example, “...misinformation about contraceptive methods. Qualitative studies from Kenya (19, 20) and other parts of Africa (23) highlight that concerns about side effects are not represented in the literature; similarly, references 11, 12, and 15 were cited, while references 29 was cited before 28, and 30 and 31 were not cited at all.”

Reviewer #4: This article is well-structured and easily comprehensible. It provides valuable insights into the effects of hormonal contraceptives, a topic that often raises questions within the community. The project contributes to the scientific understanding of this issue and offers practical recommendations. The suggestion to provide dietary and nutritional advice to users of hormonal contraceptives is particularly useful. Such knowledge is crucial for healthcare workers, as the community frequently receives information from them.

Minor Corrections Needed:

Some minor corrections are needed regarding spelling and formatting.

Examples:

Reproductive Health and Contraceptive Use

The study shows THAT that 68.3% of the WRA were using some form of contraception, a figure

that compares favourably with national trends in Kenya, where the modern contraceptive

prevalence rate (mCPR) among married women is around 58% (17).

Delimitation of the Study

This study FOCUSSED on examining effects of hormonal contraceptives on the body composition

and nutritional status of women of reproductive age residing in Kamakwa Ward of Nyeri Central

Sub-County, Nyeri County Kenya.

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Reviewer #1: Yes:  Maria Cabrera Escobar

Reviewer #2: Yes:  Dr Ezechukwu Ikenna Nwokoma

Reviewer #3: No

Reviewer #4: No

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Attachments

Attachment

Submitted filename: Hormonal Contraceptive_Maria.pdf

Hormonal contraceptives and body composition by use of stable isotope dilution techniques among women of reproductive age in Nyeri County, Kenya

PONE-D-25-16297R1

Dear Dr. Chepkorir Lang'at, 

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Kind regards,

Ozan Karadeniz

Academic Editor

PLOS ONE

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #3: All comments have been addressed

Reviewer #4: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #3: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #3: Yes

Reviewer #4: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors have addressed most of my comments. I have provided minor additional comments in two documents. It appears that the document attached for revision contained multiple versions of the same file. I initially reviewed the original version, where my comments had not yet been addressed; only after completing that review did I notice a revised version further down, which I also reviewed. In hindsight, I should not have reviewed the earlier version. This situation was unusual for me and resulted in unnecessary time and some confusion.

Reviewer #3: The authors did great work in addressing the reviewers' comments. They expanded the introduction by adding valuable information, explained the use of various group and included the multiregression analysis, as well as edited the references section.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean? ). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy .

Reviewer #1: No

Reviewer #3: No

Reviewer #4: No

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