Ultra-Rapid Freezing and Rapid Freezing Methods in Clinical ICSI Program: Effects on Sperm Biological Characteristics, DNA Methylation Stability, DNA Methyltransferase Activity, and Embryo Morphokinetics

Table 5

Comparison of morphokinetics individual and calculated variables between groups.

Time lapse parameters	Fresh group (n = 249); mean ± SD	Ultra-rapid freezing group (n = 243) mean ± SD	Rapid group (n = 238); mean ± SD
tPB2	3.97 ± 0.91	4.67 ± 1.16	4.61 ± 1.12
tPNa	7.97 ± 0.90	8.40 ± 0.81	8.63 ± 0.99^†
tPNf	23.55 ± 1.76	24.14 ± 2.47	24.79 ± 3.03^†
t2	26.9 ± 1.85	28.22 ± 3.50	28.15 ± 3.60
t3	37.04 ± 2.54	37.78 ± 3.48	37.83 ± 3.05
t4	39.69 ± 2.61	40.48 ± 3.74	40.54 ± 3.01
t5	49.04 ± 3.48	50.19 ± 4.34	49.92 ± 3.23
t6	51.57 ± 2.71	52.53 ± 3.51	52.22 ± 2.74
t7	53.00 ± 2.61	53.77 ± 3.31	54.06 ± 2.69
t8	57.30 ± 3.42	58.31 ± 4.06	59.39 ± 5.11^†
tM	95.20 ± 2.75	96.02 ± 1.74	96.44 ± 3.40
tB	107.39 ± 4.11	108.00 ± 4.89	108.45 ± 5.00
tEB	115.95 ± 2.45	116.54 ± 2.83	116.77 ± 2.55
cc2	10.13 ± 3.23	9.56 ± 4.63	9.68 ± 4.60
s2	2.65 ± 1.69	2.70 ± 1.82	2.68 ± 1.75
cc3	12.00 ± 4.14	12.41 ± 5.46	12.10 ± 4.43
s3	8.28 ± 5.08	8.06 ± 4.30	9.32 ± 5.91

Note. tPB2, time to detached the second PB from oolema; tPNa, time to PN appearance; tPNf, time to PN disappearance; t2, first cleavage (2-cell stage); t3, second cleavage (3-cell stage); t4, 4-cell stage; t5, 5-cell stage; t6, 6-cell stage; t7, 7-cell stage; t8, 8-cell stage; tM, time to morula; tB, time to blastocyst; tEB, time to expanded blastocyst; cc2 = t3–t2; s2 = t4–t3; cc3 = t5–t3; s3 = t8–t5. , , ; the different between fresh with ultra-rapid freezing and rapid groups. ^†; the different between ultra-rapid freezing with rapid groups.