Table 2. Maturation and fertilization status following IVM and IVF of oocytes vitrified in the presence of either trehalose or sucrose.

Treatment groups	No. of oocytes
	Total*	GVBD	Matured$	Penetrated	Normal	MPN	Monospermy
		(% total)	(% total)	(% GVBD)	(% GVBD)	(% penetrated)	(% penetrated)
Control	100	95 (95.0 ± 3.0)	73 (70.0 ± 6.8)	43 (44.6 ± 9.3)	12 (12.5 ± 2.7)	43 (100)	17 (43.7 ± 6.3)
Vitrified-trehalose	100	94 (94.0 ± 2.0)	57 (57. 0 ± 1.9)	48 (61.4 ± 4.4)	18 (19.3 ± 3.0)	55 (94.6 ± 1.8)	31 (54.1 ± 3.4)
Vitrified-sucrose	100	88 (88.0 ± 4.3)	55 (55.0 ± 1.0)	41 (45.9 ± 10.1)	19 (21.0 ± 7.0)	37 (90.7 ± 3.6)	27 (65.9 ± 7.5)

Before vitrification, oocytes were equilibrated in a total of 4% (v/v) CPA (ethylene glycol + propylene glycol (1:1)) for 15 min followed by a brief (approx. 40 sec) washing and vitrification in a total of 35% (v/v) CPA supplemented with either trehalose or sucrose (0.3 M). Four replicates were performed. Percentage data are presented as mean ± SEM values. No significant differences were detected among treatment groups (P < 0.05). MPN = male pronucleus; GVBD = germinal vesicle breakdown. * After vitrification IVM and IVF, only live oocytes used to assess nuclear and fertilization status. ^$At or beyond the MII stage at 10 h after IVF.