Dear Dr Le Vance,

Thank you for submitting your manuscript entitled "Teleultrasound in obstetrics: a systematic review and meta-analysis" for consideration by PLOS Medicine. Apologies for the delay in providing you with an initial decision.

Your resubmission has now been evaluated by the PLOS Medicine editorial staff as well as by an academic editor with relevant expertise and I am writing to let you know that we would like to send your manuscript out for external peer review.

However, before we can send your manuscript to reviewers, we need you to complete your submission by providing the metadata that is required for full assessment. To this end, please login to Editorial Manager where you will find the paper in the 'Submissions Needing Revisions' folder on your homepage. Please click 'Revise Submission' from the Action Links and complete all additional questions in the submission questionnaire.

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Please re-submit your manuscript within two working days, i.e. by Sep 15 2025.

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Feel free to email me at atosun@plos.org or us at plosmedicine@plos.org if you have any queries relating to your submission.

Kind regards,

Alexandra Tosun, PhD

Senior Editor

PLOS Medicine

Dear Dr Le Vance,

Many thanks for submitting your manuscript "Teleultrasound in obstetrics: a systematic review and meta-analysis" (PMEDICINE-D-25-03073R1) to PLOS Medicine. The paper has been reviewed by subject experts and a statistician; their comments are included below and can also be accessed here: [LINK]

Please note that we have invited some of the same reviewers who evaluated the previous version of the manuscript and invited new reviewers as well.

As you will see, the reviewers find that the meta-analysis strengthened the paper. However, they still have some additional questions and concerns, e.g. about the inclusion and exclusion of studies. After discussing the paper with the editorial team and an academic editor with relevant expertise, I'm pleased to invite you to revise the paper in response to the reviewers' comments. We plan to send the revised paper to some or all of the original reviewers, and we cannot provide any guarantees at this stage regarding publication.

In addition to these revisions, you may need to complete some formatting changes, which you will receive in a follow up email. A member of our team will be in touch with a set of requests shortly. If you do not receive a separate email within a few days, please assume that checks have been completed, and no additional changes are required.

When you upload your revision, please include a point-by-point response that addresses all of the reviewer and editorial points, indicating the changes made in the manuscript and either an excerpt of the revised text or the location (eg: page and line number) where each change can be found. Please also be sure to check the general editorial comments at the end of this letter and include these in your point-by-point response. When you resubmit your paper, please include a clean version of the paper as the main article file and a version with changes tracked as a marked-up manuscript. It may also be helpful to check the guidelines for revised papers at http://journals.plos.org/plosmedicine/s/revising-your-manuscript for any that apply to your paper.

We ask that you submit your revision by Nov 24 2025. However, if this deadline is not feasible, please contact me by email, and we can discuss a suitable alternative.

Don't hesitate to contact me directly with any questions (atosun@plos.org).

Best regards,

Alexandra

Alexandra Tosun, PhD

Senior Editor

PLOS Medicine

atosun@plos.org

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Comments from the reviewers:

Reviewer #1: See attachment

Michael Dewey

Reviewer #2: The authors have performed the requested systematic review and meta-analysis, which has strengthened the main conclusions of the revised version of the manuscript. Therefore, I confirm my initial recommendation to accept it.

Reviewer #3: I reviewed manuscript 01111R2 but was not a reviewer of the initial submission of 03073.

Having examined this revised version, it is clear that the authors have addressed the main issues raised previously.

The results, which were formerly lengthy and somewhat repetitive, are now better structured, supported by summary tables and figures, and enriched by the addition of a meta-analysis.

This is the most important improvement, moving the work beyond narrative synthesis to provide quantitative pooled evidence on feasibility, diagnostic accuracy, and non-inferiority compared with conventional ultrasound.

The clinical indications are more clearly delineated, with diagnostic accuracy now stratified by anatomical structure and indication.

Risk of bias assessments, previously relegated to supplementary materials, are integrated into the main text, which strengthens the critical appraisal.

The discussion has also been broadened to include ethical, regulatory, and equity considerations, with greater attention to barriers such as infrastructure, digital literacy, and social determinants of uptake.

The roadmap for future research is more specific and operational, identifying methodological standards and clinically relevant outcomes.

Some limitations remain, especially the reliance on studies of low methodological quality and a still somewhat superficial treatment of ethical and regulatory issues, but overall the manuscript now represents a rigorous and substantially improved contribution.

It is the most comprehensive and quantitatively informed review to date on obstetric teleultrasound and is in my view suitable for publication once minor refinements are made.

Reviewer #4: The authors seek to perform a review to evaluate if teleultrasound is feasible, acceptable, diagnostically accurate and cost effective for antenatal care.

Main concern: Of the 5781 papers screened, 126 full texts were reviewed, and 61 studies were selected for inclusion. I am impressed with the number of articles that have been left out and that this process has not been performed adequately. For example, looking at Table S4, I found the work by Toscano et al "69 Testing a telediagnostic obstetric ultrasound system without a trained sonographer in a low-resource Peruvian clinic". This work was left out since it was a conference abstract. However, there is a full text article appears that can be found in:

Toscano, Marika, et al. "Testing telediagnostic obstetric ultrasound in Peru: a new horizon in expanding access to prenatal ultrasound." BMC Pregnancy and Childbirth 21.1 (2021): 328.

Furthermore, this article appears in other reviews about the same topic, including Kariman et al, a work which is cited as [3] in references of this submission. I strongly suggest the authors validate thoroughly that their inclusion/exclusion criteria have been followed correctly.

The article presents an adequate organization, presenting a table with the articles considered for the results and discussion of each section. Something that I found odd is that at the beginning of each section, the authors referenced all the considered articles. However, this list of references does not match exactly the articles presented in the table of that section. For instance, in Section 3.4.5 Three- and four-dimensional ultrasound, they mentioned they investigated 5 studies [23,39,52,60,63]. However, in Table 6, they show studies [22,23,39,52,60,63]. Same thing happens in Section 3.4.7 Low- and middle-income countries. At the beginning of the Section, they introduced studies [35,38,47,49,76,78]. However, the Table 8 shows [37,38,47,49,76,78]. Please, verify.

In addition, I believe it is also important to differentiate the different clinical applications of tele-ultrasound in antenatal care. Some of the works presented aim to give a final diagnosis, whereas others target an initial screening and adequate referral to the hospital. This will pose different requirements in equipment, connectivity, operator training, etc. Could this explain your wide range of requirements showed in equipment cost or bandwidth needed? Could this also affect the discussion of image quality?

Regarding equipment and besides the previous point, it would be important to weight the year of publication and accessibility (including cost) of the equipment in the analysis. Technology and equipment have evolved considerably from 1995 to 2024. Same consideration should be considered for bandwidth.

Regarding operator training and required skills in LMICs, besides the previous point of the target medical application, it might also be interesting to add a comment about the use of AI complementing blind sweeps for widespread use. Especially, since there is a good part of the discussion focused on this point.

Any attachments provided with reviews can be seen via the following link: [LINK]

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* Please note that we expect searches to be updated to within 6 months of the time of submission.

Attachments

Attachment

Submitted filename: levance.pdf

Dear Dr. Le Vance,

Thank you very much for re-submitting your manuscript "Teleultrasound in obstetrics: a systematic review and meta-analysis" (PMEDICINE-D-25-03073R2) for review by PLOS Medicine.

Thank you for your detailed response to the reviewers' and editors’ comments. I have discussed the paper with my colleagues, and it has also been seen again by two of the original reviewers. The changes made to the paper were satisfactory to the reviewers. As such, we intend to accept the paper for publication, pending your attention to the editors' comments below in a further revision. When submitting your revised paper, please once again include a detailed point-by-point response to the editorial comments. The remaining issues that need to be addressed are listed at the end of this email.

In revising the manuscript for further consideration here, please ensure you address the specific points made by the editors. In your rebuttal letter you should indicate your response to the editors' comments and the changes you have made in the manuscript. Please submit a clean version of the paper as the main article file. A version with changes marked must also be uploaded as a marked up manuscript file. Please also check the guidelines for revised papers at http://journals.plos.org/plosmedicine/s/revising-your-manuscript for any that apply to your paper.

In addition to these revisions, you may need to complete some formatting changes, which you will receive in a follow up email. A member of our team will be in touch with a set of requests shortly. If you do not receive a separate email within a few days, please assume that checks have been completed, and no additional changes are required.

Please note, when your manuscript is accepted, an uncorrected proof of your manuscript will be published online ahead of the final version, unless you've already opted out via the online submission form. If, for any reason, you do not want an earlier version of your manuscript published online or are unsure if you have already indicated as such, please let the journal staff know immediately at plosmedicine@plos.org.

We ask that you submit your revision by Feb 27 2026. However, if this deadline is not feasible, please contact me or the journal staff (plosmedicine@plos.org) by email, and we can discuss a suitable alternative.

We look forward to receiving the revised manuscript.

Sincerely,

Alexandra Tosun, PhD

Senior Editor

PLOS Medicine

plosmedicine.org

***Please note while forming your response, if your article is accepted, you may have the opportunity to make the peer review history publicly available. The record will include editor decision letters (with reviews) and your responses to reviewer comments. If eligible, we will contact you to opt in or out.***

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Comments from Reviewers:

Reviewer #1: The authors have addressed all my points.

Michael Dewey

Reviewer #4: Authors have addressed all my previous comments.

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Requests from Editors:

As discussed via email, please update your searches to within six months of submission. We strongly encourage you to include all 2025 studies that meet your inclusion/exclusion criteria.

GENERAL

* Please confirm that your title complies with to PLOS Medicine's style. Your title must be nondeclarative and not a question. It should begin with main concept if possible. "Effect of" should be used only if causality can be inferred, i.e., for an RCT. Please place the study design ("A randomized controlled trial," "A retrospective study," "A modelling study," etc.) in the subtitle (ie, after a colon).

* Statistical reporting: Please revise throughout the manuscript, including tables and figures.

- Please report statistical information as follows to improve clarity for the reader, ""XX% (95% CI [XX,YY]; p</=)"".

- Please separate upper and lower bounds with commas instead of hyphens as the latter can be confused with reporting of negative values.

- Please repeat statistical definitions (HR, CI etc.) for each set of parentheses.

* Please ensure that all abbreviations are defined at first use throughout the text (including statistical abbreviations).

* Please ensure that tables and figures, including those in supplementary files, are appropriately referenced in the main text.

* Please review your text for claims of novelty or primacy (e.g. 'for the first time' or ‘novel’) and remove this language.

* Please confirm that any use of statistical terms (such as trend or significant) are supported by the data, and if not please remove them. The term trend should be used only when the test for trend has been conducted.

* Please provide titles and legends for all figures and tables (including those in Supporting Information files).

* Please define all acronyms used in each figure or table in the corresponding legend.

* Please confirm that you used patient-centered language. Please note that patient-centered language is constructed with the use of post-modified nouns putting the person first in the sentence structure.

* Please review your manuscript and edit to ensure compliance with our inclusive language requirements (https://journals.plos.org/plosmedicine/s/human-subjects-research#loc-categorization). For example, please revise language such as “rural Ethiopian women” (Table 8).

* Please remove the numbering from the headings (starting with ‘Introduction’).

ABSTRACT

* Please confirm that your abstract complies with our requirements, including providing all the information relevant to this study type https://journals.plos.org/plosmedicine/s/submission-guidelines#loc-abstract

* Please confirm that all numbers presented in the abstract are present and identical to numbers presented in the main manuscript text.

* In the last sentence of the Abstract Methods and Findings section, please describe the main limitation(s) of the study's methodology.

* “on a wide range of clinical outcomes” – We find this rather vague and suggest that you specify or mention a few examples, at least.

* “Identifying fetal and placental structures were frequently high using teleultrasound” – please revise for clarity.

METHODS AND RESULTS

* Thank you for providing your PRISMA checklist. Please replace the page numbers with paragraph numbers per section (e.g. "Methods, paragraph 1"), since the page numbers of the final published paper may be different from the page numbers in the current manuscript.

* Figure 2: Please note that for the last shade, the definition in the figure is ‘?10’ which we assume is supposed to be ‘<10’.

* “Four studies assessed in the first trimester, five in the second trimester, four in the third trimester, three in the first and second trimesters, 16 in the second and third trimesters, 11 in all trimesters and 20 did not disclose.” – is there a specific reason you do not cite the relevant studies here as done in the text before and after?

* Figure 7: Please note that the figure appears to be cut-off at the bottom.

* “Meta-analysis of identification rates between teleultrasound and the reference standard were available in a select number of studies for a subset of fetal and placental structures (Figure 7).” – It would be useful to mention that (only) two studies were included for meta-analysis for each subgroup.

* “Very low bandwidths (<284 Kb/s) demonstrated significantly worse image quality..” – were these statistically significant?

* “with more recent studies demonstrating a reduction in implementation cost of $10,355 - €19,356 [29,85].” – We find that presenting a range that switches between currencies is not ideal. Please revise.

DISCUSSION

* Please remove the 'conclusions' subheading from the discussion. Please also remove any other subheadings from the discussion.

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General Editorial Requests

1) We ask every co-author listed on the manuscript to fill in a contributing author statement. If any of the co-authors have not filled in the statement, we will remind them to do so when the paper is revised. If all statements are not completed in a timely fashion this could hold up the re-review process. Should there be a problem getting one of your co-authors to fill in a statement we will be in contact. YOU MUST NOT ADD OR REMOVE AUTHORS UNLESS YOU HAVE ALERTED THE EDITOR HANDLING THE MANUSCRIPT TO THE CHANGE AND THEY SPECIFICALLY HAVE AGREED TO IT.

2) Please ensure that the paper adheres to the PLOS Data Availability Policy (see http://journals.plos.org/plosmedicine/s/data-availability), which requires that all data underlying the study's findings be provided in a repository or as Supporting Information. For data residing with a third party, authors are required to provide instructions with contact information for obtaining the data. PLOS journals do not allow statements supported by "data not shown" or "unpublished results." For such statements, authors must provide supporting data or cite public sources that include it.

3) 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.

Dear Dr Le Vance,

On behalf of my colleagues and the Academic Editor, Jennifer Elizabeth Jardine, I am pleased to inform you that we have agreed to publish your manuscript "Teleultrasound in obstetrics: a systematic review and meta-analysis" (PMEDICINE-D-25-03073R3) in PLOS Medicine.

I appreciate your thorough responses to the reviewers' and editors' comments throughout the editorial process. We look forward to publishing your manuscript, and editorially there are only two remaining points that should be addressed prior to publication. We will carefully check whether the changes have been made. If you have any questions or concerns regarding these final requests, please feel free to contact me at atosun@plos.org.

Please see below the minor points that we request you respond to:

For further transparency, we suggest the following changes to the Abstract:

*Please change to: “Overall meta-analysis demonstrated teleultrasound is non-inferior for identifying anatomical structures versus the reference standard RR 1.02 (95% CI [1.00,1.03]; n= 2 studies).”

*Please change to: “Pooled diagnostic accuracy demonstrated excellent performance, with an AUC of 0.93 (n=8 studies).”

Before your manuscript can be formally accepted you will need to complete some formatting changes, which you will receive in a follow up email (including the editorial requests above). Please be aware that it may take several days for you to receive this email; during this time no action is required by you. Once you have received these formatting requests, please note that your manuscript will not be scheduled for publication until you have made the required changes.

In the meantime, please log into Editorial Manager at http://www.editorialmanager.com/pmedicine/, click the "Update My Information" link at the top of the page, and update your user information to ensure an efficient production process.

PRESS

We frequently collaborate with press offices. If your institution or institutions have a press office, please notify them about your upcoming paper at this point, to enable them to help maximise its impact. If the press office is planning to promote your findings, we would be grateful if they could coordinate with medicinepress@plos.org. If you have not yet opted out of the early version process, we ask that you notify us immediately of any press plans so that we may do so on your behalf.

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Thank you again for submitting to PLOS Medicine. We look forward to publishing your paper.

Sincerely,

Alexandra Tosun, PhD

Senior Editor

PLOS Medicine