. 2020 Jun 6;66(5):427–433. doi: 10.1262/jrd.2020-059

Table 4. In vitro development of in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) embryos derived from Second-oocytes.

Exp.	Recovery period after surgery	No. of used oocytes	No. of oocytes surviving after ICSI	No. (%) * of oocytes with 2PN formed	No. of embryos developed to
Exp.	Recovery period after surgery	No. of used oocytes	No. of oocytes surviving after ICSI	No. (%) * of oocytes with 2PN formed	2 cell	4–8 cell	Morula	Blastocyst (%) *
IVF	Control	376	–	353 (93.9) ^ab	348	335	325	319 (90.4) ^ab
	10 days	222	–	214 (96.4) ^a	213	213	206	202 (94.4) ^a
	20 days	194	–	182 (93.8) ^ab	180	176	168	154 (84.6) ^bc
	30 days	189	–	169 (89.4) ^b	161	158	146	131 (77.5) ^c
ICSI	Control	286	214	198 (92.5) ^c	192	165	144	130 (65.7) ^d
	10 days	70	64	59 (92.2) ^c	57	53	43	36 (61.0) ^d
	20 days	107	81	78 (96.3) ^c	76	69	61	59 (75.6) ^d
	30 days	97	81	79 (97.5) ^c	78	73	64	57 (72.2) ^d

Some experimental groups were not performed with control at the same time. PN: Pronuclei. * Different letters indicate significant differences by Pearson’s Chi-square test (P < 0.01).