Table 5. Blastocyst biopsy on day 5 versus day 6.

Morphokinetic parameters	Day 5		Day 6		Univariate p value	Multivariate analysis
	mean ± SD	n	mean ± SD	n		p value	OR [95%CI]
Treatment	0.50 ± 0.50	159	0.51 ± 0.50	74	0.564
Ploidy	0.55 ± 0.50	159	0.38 ± 0.49	74	0.006	0.660	1.366 [0.340–5.491]
Sex	0.48 ± 0.50	146	0.50 ± 0.50	66	0.761
ct2	2.6 ± 1.1	159	2.71 ± 1.1	74	0.486
ct3	13.1 ± 2.3	159	12.6 ± 3.8	74	0.191	ƚ
ct4	14.3 ± 2.7	159	15.3 ± 4.6	74	0.391
ct5	25.7 ± 4.5	159	27.3 ± 8.4	74	0.311
ct6	27.5 ± 4.8	159	31.0 ± 8.3	74	0.003	0.810	0.963 [0.710–1.307]
ct7	29.7 ± 6.1	158	34.9 ± 8.9	74	<0.0001	0.254	0.862 [0.668–1.113]
ct8	32.8 ± 7.7	158	40.0 ± 11.3	73	<0.0001	0.630	0.965 [0.835–1.210]
ct9	44.7 ± 6.7	146	48.6 ± 11.3	64	0.010	0.652	1.036 [0.888–1.210]
ctSC	53.2 ± 8.0	159	56.4 ± 10.5	74	0.028	0.598	1.039 [0.900–1.200]
ctM	62.4 ± 7.5	157	67.1 ± 8.9	74	0.0004	0.820	1.022 [0.846–1.234]
ctSB	69.9 ± 5.7	159	77.9 ± 6.6	74	<0.0001	0.692	1.691 [0.604–4.735]
ctB	82.3 ± 5.5	159	95.7 ± 8.2	74	<0.0001	<0.0001	0.613 [0.489–0.768]
ctEB	88.3 ± 17.4	130	105.6 ± 18.1	67	<0.0001	0.0004	0.913 [0.868–0.960]
Blast1.tB-tSB	12.4 ± 3.6	159	17.9 ± 7.1	74	<0.0001	ƚ
Blast.tSB-t2	67.3 ± 5.8	159	75.2 ± 6.6	74	<0.0001	0.315	0.600 [0.221–1.626]
cc2.t3-t2	10.5 ± 2.2	159	9.9 ± 4.1	74	0.132	0.044	1.394 [1.010–1.926]
cc3.t5-t3	12.6 ± 3.1	159	14.7 ± 7.5	74	0.038	0.672	0.957 [0.781–1.173]
s2.t4-t3	1.2 ± 2.4	159	2.7 ± 4.9	74	0.056	0.383	1.157 [0.833–1.607]
s3.t8-t5	7.1 ± 6.3	158	12.7 ± 8.8	73	<0.0001	ƚ

Comparison of standardized time lapse parameters (hours) between blastocysts biopsied on day 5 or day 6. Treatment: ICSI = 0, IVF = 1; ploidy: 0 = aneuploid, 1 = euploid; sex: 0 = male, 1 = female.

ƚ: Not Estimated due to collinearity, SD: standard deviation, n: number, OR: odds ratio, CI: confidence interval.