Embryological, clinical and ultrastructural study of human oocytes presenting indented zona pellucida
- 2 September 2013
- journal article
- research article
- Published by Cambridge University Press (CUP) in Zygote
- Vol. 23 (1), 145-157
- https://doi.org/10.1017/s0967199413000403
Abstract
Summary: Human oocyte dysmorphisms attain a large proportion of retrieved oocytes from assisted reproductive technology (ART) treatment cycles. Extracytoplasmic defects involve abnormal morphology of the zona pellucida (ZP), perivitelline space and first polar body. The aim of the present study was to describe a novel dysmorphism affecting the ZP, indented ZP. We also evaluated the clinical, embryological and ultrastructural features of these cases. We evaluated all ART treatment cycles during 7 consecutive years and found 13 treatment cycles (six patients) with all oocytes presenting an indented ZP. In addition, these oocytes presented total or partial absence of the perivitelline space, absence of resistance to ZP and oolemma penetration during microinjection, and low ooplasm viscosity during aspiration. This novel described dysmorphism was recurrent and attained all oocytes in three cases that had more than one treatment cycle. When compared with controls, data showed significant low oocyte maturity (42% versus 81.6%) and high cycle cancellation (30.8% versus 8.5%) rates, normal degeneration (3.4% versus 6.3%) and fertilization rates (69% versus 69.5%), and low pregnancy (15.4% versus 33.3%) and live-birth delivery (7.7% versus 27.7%) rates per cycle. Ultrastructure analysis revealed a zona pellucida structure with large empty electrolucent regions, an outer ZP layer with an indented surface with protuberances and a thick inner ZP that obliterated the perivitelline space. There was evidence of exocytosis of ZP material by the oocyte. In conclusion, oocytes with this novel described dysmorphism (indented ZP) are associated with low maturity, pregnancy and live-birth delivery rates.Keywords
This publication has 51 references indexed in Scilit:
- A maternally inherited autosomal point mutation in human phospholipase C zeta (PLC ) leads to male infertilityHuman Reproduction, 2011
- Gamete competence assessment by polarizing optics in assisted reproductionHuman Reproduction Update, 2011
- Small GTPases and formins in mammalian oocyte maturation: cytoskeletal organizersClinical and Experimental Reproductive Medicine, 2011
- Oocyte maturation failure: a syndrome of bad eggsFertility and Sterility, 2010
- Predictive value of oocyte morphology in human IVF: a systematic review of the literatureHuman Reproduction Update, 2010
- Impact of GnRH ovarian stimulation protocols on intracytoplasmic sperm injection outcomesReproductive Biology and Endocrinology, 2009
- Removal of spermatozoa with externalized phosphatidylserine from sperm preparation in human assisted medical procreation: effects on viability, motility and mitochondrial membrane potentialReproductive Biology and Endocrinology, 2009
- Cytoskeleton and cell cycle control during meiotic maturation of the mouse oocyte: integrating time and spaceReproduction, 2005
- Conséquences d’une dysmorphie ovocytaire sur la fécondation et le développement embryonnaire après injection intracytoplasmique d’un spermatozoïde. Étude prospective, multicentriqueGynécologie Obstétrique & Fertilité, 2002
- Three-dimensional structure of the zona pellucidaReviews of Reproduction, 1997