Table 1 Comparison of in vitro results after blastocyst transfers after ICSI and IVF on sibling oocytes in split insemination cycles

n. cycles

211

211

n. COCs

1302

1300

2602

n. MII micro-injected or inseminated oocytes

904

900

1804

n. zygotes

729

596

1325

fertilization rate

80.6

66.2

 < 0.001

73.4

n. cleaved embryos

709

573

1282

cleavage rate

97.3

96.1

NS

96.8

n. blastocysts

399

309

708

blastocyst rate/ zygote

54.7

51.8

NS

53.4

blastocyst rate/ MII oocyte

44.1

34.3

 < 0.001

39.2

n. MII oocytes per usable blastocyst

2.3

2.9

 < 0.001

2.5

n. frozen blastocysts

211

131

342

n. transferred blastocysts

188

178

366

n. implanted blastocysts

80

69

149

implantation rate

42.6

38.8

NS

40.7

n. live births

72

63

135

live birth rate

38.3

35.4

NS

36.9