Evidence map›Paper›PMID 34398401›Full record

ReviewJournal of assisted reproduction and genetics2021

On the origin of zygosity and chorionicity in twinning: evidence from human in vitro fertilization.

Enver Kerem Dirican, Safak Olgan

Abstract readReview
In one paragraph

Review in Journal of assisted reproduction and genetics, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.

0numbers the graph read from it
0cells of the map it votes in
5citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5 citing papers in PubMed.

  1. Article
  2. Review
  3. Review
  4. Review
  5. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors.

Enver Kerem DiricanFaculty of Medicine, Department of Obstetrics and Gynecology, Center for Reproductive Endocrinology and Assisted Reproduction, Akdeniz University, Antalya, 07100, Turkey. keremdirican@gmail.com.ORCID http://orcid.org/0000-0001-6230-1229
Safak OlganFaculty of Medicine, Department of Obstetrics and Gynecology, Center for Reproductive Endocrinology and Assisted Reproduction, Akdeniz University, Antalya, 07100, Turkey.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Assisted reproduction is presumed to increase monozygotic twin rates, with the possible contribution of laboratory and medical interventions. Monozygotic dichorionic gestations are supposed to originate from the splitting of an embryo during the first four days of development, before blastocyst formation. Single embryo transfers could result in dichorionic pregnancies, currently explained by embryo splitting as described in the worldwide used medical textbooks, or concomitant conception. However, such splitting has never been observed in human in vitro fertilization, and downregulated frozen cycles could also produce multiple gestations. Several models of the possible origins of dichorionicity have been suggested. However, some possible underlying mechanisms observed from assisted reproduction seem to have been overlooked. In this review, we aimed to document the current knowledge, criticize the accepted dogma, and propose new insights into the origin of zygosity and chorionicity.

Indexed as

Twinning, DizygoticTwinning, MonozygoticChorionFemaleFertilization in VitroHumansPregnancyZygoteChorionicityInner cell massIn vitro fertilizationMultifetal gestationsTrophectodermZygosity

Identifiers

PMID34398401
PMCPMC8608953

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.