極體與原核平面夾角越小胚胎品質越佳

a 角度: 原核平面與較近極體之最小夾角
b 角度: 原核平面與較遠極體之最小夾角

a角度與胚胎品質無統計關連(但alpha 角度越小可能胚胎品質越佳)
b角度越小，胚胎品質越佳

g角度與胚胎品質無關連

極體與原核平面夾角越小胚胎品質越佳
ICSI受孕之胚胎碎片fragment似乎比IVF受孕之胚胎碎片fragment為多

http://humrep.oxfordjournals.org/content/14/10/2588.full

Figure 1.

Diagram showing the measurement of α, β, and γ. α is the smallest angle between a line drawn through the axis of the pronuclei and the closest polar body. β is the smallest angle between the same line and the furthest polar body. γ is the angle between the two polar bodies using the centre of the oocyte for reference. The placement of these angles may appear differently depending upon the angle of observation and the orientation of the polar bodies.

Table II.

Comparison of ICSI and IVF embryos

	IVF	ICSI	Significance
Embryos (n)	127	124
2PN = two pronuclear stage.
Cryopreserved at 2PN	0	4
Study group (n)	127	120
Morphology (%)
Good	47 (37.0)	40 (33.3)
Medium	72 (56.7)	66 (55)
Poor	7 (5.5)	4 (3.3)
Failed to cleave (%)	1 (0.8)	10 (8.3)	P < 0.05

Table III.

Relationship between pronuclear placement and cleavage regularity in IVF and ICSI embryos

	IVF (n = 127)		ICSI (n = 120)
	Eccentric PN	Central PN	Eccentric PN	Central PN
PN = pronuclei.
aP < 0.05.
bP < 0.05.
cNot significantly different.
Number (%)	15 (11.8)a	112 (88.2)	4 (3.3)a	116 (96.7)
No cleavage	0	1	3	7
Regular cleavage	8	89	1	96
Irregular cleavage (as % of all cleaving embryos)	7 (46.7%)b	22 (19.8%)b,c	0	13 (11.9%)c

Figure 2.

Comparison of numbers of cleavage divisions in IVF (n = 127) and ICSI (n = 120) embryos on day 2, presented as percentages