A successful twin healthy live birth achieved from eggs with a rare perivitelline space abnormality: A case report


Background: Phenotypic dysmorphism is not rare to be found in the human oocyte, especially in the perivitelline space, which are among the most important aberration of the extra cytoplasmic component.

Case Presentation: The case is of a 30-yr-old woman with no previous pregnancy, attempting an in vitro fertilization treatment for the first time. Given the extraordinary quantity of granular particles found in the perivitelline space, visible after the stripping procedure, it was not possible to establish the presence and position of the first polar body to appreciate the correct oocyte maturation (metaphase 2). Nevertheless, all the eggs were injected by the intracytoplasmic sperm injection. A time lapse incubator was used to perform the entire culture. Hence, a record of 6 days culture video was obtained. Only 2 eggs could fertilize correctly and reach the blastocyst stage on day 6. The embryos were frozen and subsequently transferred as frozen embryo transfer following the next menstrual cycle.

Conclusion: The exceptional presence of granular particles in the perivitelline space, which reminds us for aspects and behavior of the granulosa cells, seems to affect the fertilization but not the blastocysts quality. As a matter of fact, the woman, after the embryo transfer, achieved a successful twin live birth.

Key words: Oocyte, Granulosa cell, Intracytoplasmic sperm injection, Perivitelline space, Case report.

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