Correlation Between Oocyte and Embryo Mechanical Properties on Embryo Development and Clinical Pregnancy After In Vitro Fertilization

In the current practice of in vitro fertilization (IVF), clinicians often transfer multiple
embryos to the patient at once in an effort to maximize chances of pregnancy. This practice
results in a high rate of multiple births which increase the risks of complications for
mothers and children.

The investigators in this study have developed a novel, noninvasive marker of embryo
viability which is based on measuring embryo mechanical properties at the oocyte or the
1-cell stage. The investigators would like to test whether human oocyte or embryo mechanical
properties are predictive of subsequent development, clinical pregnancy, and compare their
predictive power to that of a morphological assessment (the current gold standard). Using
this approach, clinicians could more confidently move toward single embryo transfer, provided
more individualized counseling for patients undergoing oocyte cryopreservation, as well as
improve pregnancy rates after IVF.

This is a pilot observational study. Although investigators will measure the mechanical
properties of all participant oocytes and embryos, no prediction of embryo viability will be
made, and there will be no intervention in choosing which embryos to transfer to
participants. The data from this study will eventually be used to find a range of oocyte and
embryo mechanical parameters which are predictive of high developmental potential, and will
serve as the basis for an interventional study in the future.

Inclusion Criteria:

- Between the ages of 21 and 45

- Undergoing intra-cytoplasmic sperm injection (ICSI) at Stanford Fertility, Shenzhen
IVF clinic, or Taiwan IVF group between August 2015 and August 2018

Exclusion Criteria:

- Using gestational carrier or donor eggs

- Using cryopreserved eggs

- Fewer than 5 oocytes collected