Prediction of embryo developmental potential and pregnancy based on early stage morphological characteristics.
OBJECTIVE
To analyze the association between morphological details at different stages of culture with blastocyst development, with an aim to improve selection for transfer.


METHODS
Retrospective audit of data.


METHODS
Tertiary referral center and university hospital.


METHODS
Two hundred sixty-eight couples underwent 357 treatment cycles.


METHODS
Oocyte pickups for IVF or intracytoplasmic sperm injection (ICSI) after ovarian stimulation. Embryos were individually cultured and examined on days 0-2 for morphological details and developmental characteristics, and selected for transfer, freezing, or further culture.


METHODS
The association of blastocyst development and pregnancy with morphological characteristics.


RESULTS
Five morphological characteristics (appearance of the cytoplasm, pronuclei and nucleoli, cytoplasmic deficit, and developmental rate) showed the strongest association with blastocyst development. By combining information from all days of culture into a cumulative score, prediction was greatly improved, compared to only using day 2 morphology. Cytoplasmic dysmorphisms of the oocyte, including accumulation of smooth endoplasmic reticulum, were associated with poor developmental performance. Differential weighting of these characteristics was included in a new embryo scoring system, which showed a strong correlation with implantation.


CONCLUSIONS
Weighting individual morphological characteristics of zygotes and embryos and combining them into a cumulative embryo score can improve selection of embryos for transfer.
Sjöblom
Peter
P
School of Women's and Children's Health, University of New South Wales, Australia. peter.sjoblom@fcivf.com
Menezes
Judith
J
Cummins
Lisa
L
Mathiyalagan
Bagyalakshmi
B
Costello
Michael F
MF
D000328:Adult; D004624:Embryo Transfer; D004622:Embryo, Mammalian / Q000166:cytology*; D047108:Embryonic Development; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011379:Prognosis; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*