- Study question: Do cleavage-stage embryos obtained from oocytes matured in vitro after pre-incubation with a phosphodiesterase inhibitor (IBMX) carry more chromosomal abnormalities than those generated from oocytes matured in vivo?
- Summary answer: The rate and type of chromosomal abnormalities in normally developing cleavage-stage embryos generated with an in vitro maturation (IVM) system including pre-incubation with IBMX are not different from those observed in supernumerary embryos obtained from oocytes matured in vivo.
- What is known already: Very limited information is available about the chromosomal constitution of IVM embryos. Previous studies were carried out using FISH on single biopsied blastomeres or arrested whole embryos and only provided fragmentary information on chromosomal abnormalities in IVM embryos. There is no systematic study of chromosomal abnormalities in all blastomeres of human Day 3 embryos with good morphology.
- Study design, size, duration: BetweenJuly 2012 and December2012, 16 young (age,35 years old) egg donors underwent 18IVM cycles for the generation of research embryos. Eighteen embryos developed to Day 3 and were analysed using array comparative genomic hybridization (aCGH).
- Participants/materials, setting, methods: Immature oocytes were retrieved from 2 to 10 mmfollicles after mild ovarian stimulation with gonadotrophins but without hCG ovulation trigger. At collection, oocyteswere pre-incubated with 3-isobutyl-1-methylxanthine (IBMX), a phosphodiesterase inhibitor and matured in vitro. After IVMculture,mature oocyteswere microinjected with sperm froma single donor. Embryos were cultured to Day 3 after ICSI and all blastomeres of 18 good-morphology embryos were collected individually for aCGH.
- Main results and the role of chance: Oocyte maturation rate in vitro was 50.2% (120/239). The mean fertilization rate was 68.3% (82/120) and 30.5% (25/82) of fertilized oocytes developed into a morphologically good quality embryo on Day 3 after ICSI. Of these, 18 embryos that developed well up to Day3 were analysed usingaCGH.Eighty of the 123 blastomeres analysed showedat least one chromosomal abnormality. Three out of eighteen embryos had completely normal cells.Asingle embryocarried a meiotic abnormality, 11 embryoswere mosaic and three were chaotic. Although the aneuploidy data of this study are too limited to allow statistical analysis, these data are comparable to our own published data on the chromosome constitution of whole day 3 and day 4 embryos after conventional ART.
Original languageEnglish
Pages (from-to)653-663
Number of pages11
JournalHuman Reproduction
Volume30
StatePublished - 2015

    Research areas

  • chromosomal abnormality, Single-cell aCGH, in vitro maturation, embryo

ID: 2489615