PONE-D-21-09227

Association of maternal obesity with adverse pregnancy outcome and neonatal death: evidence from South and South-East Asian countries

PLOS ONE

Dear Dr. Haque,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

In particular, data analysis seems unsatisfactory.  

Please submit your revised manuscript by Jun 24 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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We look forward to receiving your revised manuscript.

Kind regards,

Calistus Wilunda, DrPH

Academic Editor

PLOS ONE

Additional Editor Comments (if provided):

1. Table 1 includes both descriptive and inferential (95% CIs) statistics. Given that the aim is not to estimate the prevalence of participants with different characteristics in the population, it is not useful to present the 95% CIs. It is more meaningful to show the distribution of the potential confounding variables (rows) according to the exposure variable (column). This will help in assessing for imbalances in the distribution of the confounders.

2. It is necessary to properly account for the sampling weights when pooling data across surveys. It is not clear how sampling weights were handled in this paper. This is useful reference when dealing with weights when analyzing DHS data Multilevel Modeling Using DHS Surveys: A Framework to Approximate Level-Weights [MR27] (dhsprogram.com)

3. It is also unclear whether other features of the DHS survey i.e. strata and clusters, were properly accounted for in the analysis.

4. Was multilevel analysis considered?

5. Please present both unadjusted and adjusted ORs.

6. In Table 3, it is unnecessary to present ORs for potential confounders.

7. Did you explore for any interactions?

8. In the tables, it is not easy to visually distinguish between variables their categories.

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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: Yes

Reviewer #2: Yes

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

Reviewer #1: I Don't Know

Reviewer #2: No

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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

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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: No

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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: Thank you for the opportunity to contribute to the peer review process for this research. The study aims to analyze the association between maternal obesity and adverse pregnancy outcome and neonatal death in South and South-East Asian countries. The study is interesting and provides novel data on the association in South and South-East Asian Countries. However, this paper has some points that need to be clarified:

Moderate considerations:

1) In Methodology section, authors should indicate which was the statistical package that they used for data analysis.

2) In Methodology section (line 106), the authors say “This research selected 8 out of 15 countries in South and South-East Asia..”. I suggest to the authors indicate which were the countries that they included in the study.

3) Lines 134-144, the explanation about the BMI is confusing. The authors mention the BMI categorization according to the WHO authors: “Maternal weight status was the exposure of interest, and it was ascertained through the mother’s BMI. BMI was calculated as weight in kg divided by the height in m2, and it was categorised into four groups following the WHO guidelines, namely, underweight (BMI <18.50), healthy weight (BMI 18.50 to <25.00), overweight (BMI 25.00 to <30.00) and obese (BMI ≥30) (2)”. And after that they say “Since the targeted population of this study was South and South-East Asia, we used the cut off points of BMI for Asians, which are categorised as underweight (BMI< 18.50), healthy weight (BMI 18.50 to 22.90), overweight (BMI 23 to 26.9) and obese (BMI> 27) (19)”. If the authors used the BMI for Asians categorization, it is unnecessary to indicate the WHO BMI scores. Simply naming it, I think it is enough, and it makes the text easier to understand. It would be necessary to add the WHO reference.

4) The authors indicate in the abstract the range of years from which they collected data for the study. However this information is missing in Methodology section. I suggest that the authors also indicate this information in the text (and not only in figure 1).

Minor considerations:

5) Introduction, lines 73-76. In order to unify the referenced format, please remove the year in parentheses and indicate the reference number immediately after each author.

6) In Methodology section, lines 103-105, the authors say “The study pooled the most recent survey in eight South and South-East Asian countries”. Again, in line 107 they say “This research selected 8 out of 15 countries in South and South-East Asia”. From my point of view this information is redundant. I suggest to the authors unify this information in the same sentence/paragraph.

7) Authors should use past tense in the manuscript. For example, line 108 “The remaing seven countries are excluded..” should be written “were”. Please, check it in the whole text.

8) In References section, the reference 8 is incomplete.

Reviewer #2: Summary

This study investigated whether maternal obesity is a risk factor of adverse reproductive health outcomes (miscarriage, stillbirth, early neonatal mortality and late neonatal mortality) in South and South-East Asian countries.

The study used pooled data from the most recent DHS survey from 8 South and South-East Asian countries. Multivariate logistic regression was deployed to check the relationships between

maternal obesity and fetal deaths

It is found that maternal obesity associated with a greater risk of perinatal and early neonatal deaths.

Major comments:

Overall this paper addresses the important issues. However, a number of improvements are needed. Some key points are listed below:

• In this study, authors sometime mention perinatal and neonatal death, sometime adverse reproductive health outcome, and sometime foetal death. It should be consistence. Also, what is the meaning of foetal death?

• In the first paragraph of the introduction, authors told about adults overweight and obese. The authors should give the world statistics for maternal obese.

• In line 74-76 authors identify the key reasons for neonatal death but didn’t mention the reasons “Baroni et al. (2021) investigated the neonatal mortality rates in Brazil, whereas Liu et al. (2020) and Abdul-Mumin et al. (2021) investigated the key reasons for neonatal death in China and Ghana, respectively, including preterm birth (7–9)”

• This study used recent pooled data from 8 South and South-East Asian countries but for Bangladesh this study used old dataset.

• This study used multivariable logistic regression model to explore the association between exposure and outcome. But all the outcome proportion less than 10% better to use Poisson regression. Moreover, this study used multi-country data, so there is some country level variation for each outcome. For the multi-country data better to use multi-level approach.

• This study used some upper-middle income country and some lower-middle income countries. Authors should preform sensitivity analysis.

• In the abstract conclusion, authors mention “Obese women need to follow antenatal care visits and deliver at the institutional facility centre that can offer obstetrics and early neonatal care” but they didn’t discuss in the main conclusion. Conclusion should be consistence.

• In the conclusion, authors mention “An effective intervention to maintain recommended weight and lifestyle choices of mother is needed to reduce the number of cases of stillbirth, miscarriage and neonatal death. Moreover, cost-effective community-based strategies to improve maternal education are required in this region to achieve SDG Target-3, which aims to ensure healthy lives and promote the well-being of people of all ages by 2030”. It would be better if the authors mention what kind of effective intervention and cost-effective community-based strategies are needed?

Minor comment:

• I found several mistakes in references styles. If the reference has doi and volume number don’t need to write [Internet] and available from. Please follow the journal reference style.

• Reference number 8 incomplete.

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Reviewer #1: No

Reviewer #2: Yes: Md Rashedul Islam

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PONE-D-21-09227R1

Association of maternal obesity with fetal and neonatal death: evidence from South and South-East Asian countries

PLOS ONE

Dear Dr. Haque,

Thank you for submitting your revised manuscript to PLOS ONE. One of the reviewers has asked for further clarification on data analysis, particularly on how weighting of the pooled data was performed. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Sep 16 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

• A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.
• A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.
• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Calistus Wilunda, DrPH

Academic Editor

PLOS ONE

Journal Requirements:

Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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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 #2: 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 #2: Yes

**********

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

Reviewer #2: Yes

**********

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 #2: 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 #2: Yes

**********

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 #2: Thank you for addressing my comments. I am satisfied to your answer. Still, I have some quarries.

1. You have pooled data from 8 countries. Where is weighting? I mean your data weighting after pooling as you deal with multiple countries with wide variation in their population? E.g. India have 87.05% population (Figure 1). Could you please explain more detail about weight?

2. It is not clear how weighting was done in the multilevel analysis.

3. It is not clear how many levels of multilevel analysis were performed. Please mention in the statistical analysis section.

4. This study conclusion and recommendation not consist with study findings. In the conclusion this study mentions about antenatal care visit but didn’t use the variable in the analysis.

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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 #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Association of maternal obesity with fetal and neonatal death: evidence from South and South-East Asian countries

PONE-D-21-09227R2

Dear Dr. Haque,

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.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Calistus Wilunda, DrPH

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

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 #2: All comments have been addressed

**********

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 #2: Yes

**********

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

Reviewer #2: Yes

**********

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 #2: Yes

**********

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 #2: Yes

**********

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 #2: (No Response)

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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 #2: No