Conjoined Twins Complicating a Dichorionic Triplet Pregnancy after Intracytoplasmic Sperm Injection: A Case Report and Review of the Literature

Round 1

Reviewer 1 Report

This is an interesting case about conjoined twin, as the author report, the case was diagnosed based on an ultrasound examination showing that embryos B and C appeared fused at their sternum and their hearts were fused at their atrial level. But figure 1 does not give us the information.  The author should present a detailed image of the diagnosis mentioned above.

Author Response

Reviewer 1

This is an interesting case about conjoined twin, as the author report, the case was diagnosed based on an ultrasound examination showing that embryos B and C appeared fused at their sternum and their hearts were fused at their atrial level. But figure 1 does not give us the information.  The author should present a detailed image of the diagnosis mentioned above.

Answer: We thank the reviewer for their comment but unfortunately, due to technical problems we couldn’t find other saved images depicting CT and in particular their heart anatomy.

Reviewer 2 Report

This is a case report of dichorionic-diamniotic triplets complicated by conjoined twins in a monochorionic sac after ISCI procedure. Additionally the authors made relevant literature review on the CT and triplet pregnancies. It is a valuable description of the very rare clinical situation with the proposal of modern approach. I find it very useful in daily practice of a fetal specialist.

1/ Replace "mini-review" with just "review" in your title.

2/ I cannot find the table 1 you mention about.

3/ Specify why you did not offer cell free fetal DNA testing based on NGS e.g. SNP to check for genetic conditions and zygosity of the triplets and conjoined twins (CT).

4/ What was the gender of CT in your case? Was it the same as the survivor? You mentioned that females as more predominant for being affected by CT.

5/ Was it monozygotic or dizygotic CT? What is the mechanism for MZ vs DZ conjoining? It would be very interesting and educative for readers.

6/ You may want to present as a graph different types of CT based on proposed mechanisms in mono vs dizygotic and mono vs dichorionic multiple pregnancies.

7/ Why you chose potassium chloride and not cord occlusion (e.g. laser ablation or radiofrequency) for selective termination? You mentioned about possible vessel connections even in dichorionic pregnancies

Thank you

Author Response

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Author Response File: Author Response.docx

Reviewer 3 Report

It is a well-written, interesting case report and review of a relevant literature. The case is very radę and it is important to publish such studies in order to improve prenatal diagnostics and managemng.

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

This is a case report about conjoined twins diagnosed at early pregnancy but the authors can not provide the images for the diagnosis they describe as " embryos B and C appeared fused at their sternum  and their hearts were fused at their atrial level. The heart of embryo C consisted of three chambers with the left sided atrioventricular valve being atretic and the posterior sided ventricle being hypoplastic. The heart of embryo B consisted of four chambers and there was a large ventricular septal defect. Those description in the manuscript should be deleted.

Author Response

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Author Response File: Author Response.docx

Round 3

Reviewer 1 Report

The authors had responded me well.