Table 3 Characteristics of embryo transfer and pregnancy outcomes in different groups

Transfer outcomes

No. of patients

61

97

112

175

No. of total FET cycles

86

123

156

227

No. of total embryos transferred

103

138

192

270

Average of embryos transferred per cycle

1.2 ± 0.4

1.1 ± 0.3

0.136

1.2 ± 0.4

1.2 ± 0.4

0.327

No. of embryos transferred per cycle

0.135

0.326

1

69/86

(80.23)

108/123

(87.80)

120/156

(76.92)

184/227

(81.06)

2

17/86

(19.77)

15/123

(12.20)

36/156

(23.08)

43/227

(18.94)

Stage of embryo transferred, n (%)

0.649

0.281

Cleavage embryo

65/103

(63.11)

91/138

(65.94)

167/192

(86.98)

225/270

(83.33)

Blastocyst

38/103

(36.89)

47/138

(34.06)

25/192

(13.02)

45/270

(16.67)

Endometrial thickness (mm)

9.0

(8.3, 9.7)

9.1

(8.5, 10.1)

0.207

9.0

(8.2, 9.8)

9.2

(8.4, 10.0)

0.128

Endometrial preparation, n (%)

0.526

0.193

HRT cycles

67/86

(77.91)

104/123

(84.55)

111/156

(71.15)

176/227

(77.53)

Nature cycles

6/86

(6.98)

4/123

(3.25)

11/156

(7.05)

20/227

(8.81)

Ovulation induction cycles

1/86

(1.16)

1/123

(0.81)

3/156

(1.92)

2/227

(0.88)

Down-regulation + HRT cycles

12/86

(13.95)

14/123

(11.38)

31/156

(19.87)

29/227

(12.78)

Pregnancy outcomes, n (%)

Biochemical pregnancy rate

44/86

(51.16)

63/123

(51.22)

0.994

35/156

(22.44)

53/227

(23.35)

0.835

Clinical pregnancy rate

31/86

(36.05)

54/123

(43.90)

0.255

29/156

(11.33)

37/227

(16.30)

0.560

Ongoing pregnancy rate

24/86

(27.91)

44/123

(35.77)

0.232

17/156

(10.90)

25/227

(11.01)

0.972

Miscarriage rate

7/31

(22.58)

12/54

(22.22)

0.970

13/29

(44.83)

15/37

(40.54)

0.727

Live birth rate

24/86

(27.91)

42/123

(34.15)

0.340

16/156

(10.26)

22/227

(9.69)

0.856

Cumulative clinical pregnancy rate

31/78

(39.74)

54/111

(48.65)

0.226

29/154

(18.83)

37/214

(17.29)

0.704

Cumulative live birth rate

24/78

(30.77)

42/111

(37.84)

0.316

16/154

(10.39)

22/214

(10.28)

0.973