PONE-D-20-19757

The incidence, maternal, fetal and neonatal consequences of single intrauterine fetal death in monochorionic twins: a prospective observational UKOSS study

PLOS ONE

Dear Dr. Morris,

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.

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thank you for submitting this interesting study please response to the reviewers comments in addition please add the interval time between sIUFD and delivery as this may be pertinent when looking at outcomes of maternal and fetal wellbeing

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PLOS ONE

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Reviewer #1: Yes

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Reviewer #1: Yes

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Reviewer #1: Yes

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Reviewer #1: Yes

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Reviewer #1: This prospective UK-based study is novel, the topic is of high clinical importance for subspecialists caring for twins and the figures described are useful for counselling. The manuscript is well written and conclusions are clear and logical.

The number of cases identified was significantly lower than the estimated 253, but the authors have addressed this well in the discussion and it does not appear that a significant number of cases are likely to be missed.

A few questions (I appreciate this data may not be available but I think would be of interest to readers if it could be included):

Of those with TTTS, what were the details for mean gestation etc? Were there any noticeable differences in the deaths between those that did and did not have intervention? Was there anything to add about gestations at which fetal therapy was performed and Staging of TTS at time of intervention.

For the sepsis cases what was the timeframe relationship to the IUFD and did this result in second twin demise?

What were the causes of the two NND in co-twins (from certificates)?

Is there anything to explain why only 36 have brain imaging antenatally? Was TOP offered for the 7 with findings that were abnormal antenatally? If so, how many accepted TOP? Similarly, is there any indication of why only 9/62 in NNU have brain imaging? I think the lack of provision of CNS imaging and CNS follow-up for surviving twins is the most striking finding of the study and it would be good to add these details if they are available and also to discuss how the authors would propose to address this variation in provision across the UK.

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Reviewer #1: No

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The incidence, maternal, fetal and neonatal consequences of single intrauterine fetal death in monochorionic twins: a prospective observational UKOSS study

PONE-D-20-19757R1

Dear Dr. Katie Morris,

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,

Andrew Sharp, PhD

Academic Editor

PLOS ONE

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