LAUSR

OBJECTIVE To determine the effect of patient and treatment parameters on 19 embryo morphokinetic parameters using pronuclear fading as time zero. DESIGN Single-site, retrospective cohort analysis. SETTING Fertility treatment center. PATIENTS(S) Patients undergoing treatment between September 2014 and January 2016 (n = 639) whose embryos were cultured in the EmbryoScope for 6 days (n = 2,376). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Multiple regression analysis of body mass index; maternal age; infertility diagnosis; treatment type; suppression protocol on time to each cellular division (tn): t2, t3, t4, t5, t6, t7, t8, t9, time to start of compaction (tM), start of blastulation (tSB), full blastocyst (tB); and interval measurements: s2, s3, cc2, cc3, cc4, t9-tM, tM-tSB, and tSB-tB. Beta coefficients were analyzed to quantify any significant effects. RESULT(S) Embryos appeared to be subtly affected by patient and treatment parameters, exhibiting complex relationships between various morphokinetic parameters and specific patient and treatment factors, rather than a systemic effect. CONCLUSION(S) These findings outline the need for the consideration of confounding factors when assessing an embryo's ability to achieve implantation. Although morphokinetic parameters have been related to embryo viability, it is likely that this will vary depending on the embryo's origin.