Table 1 Baseline characteristics and pregnancy outcomes of patients with single frozen-thawed euploid blastocyst transfer

N

219

55 (25.11%)

66 (30.14%)

98 (44.75%)

Female age at oocyte retrieval (y)

30.21 ± 3.87

30.85 ± 4.40

30.88 ± 3.85

29.41 ± 3.44

0.021

BMI (kg/m2)

22.47 ± 2.66

22.97 ± 2.59

22.84 ± 2.59

21.93 ± 2.67

0.025

Infertility duration (y)

2.00 (1.00–4.00)

2.00 (1.00–4.00)

2.00 (1.00–4.00)

2.00 (1.00–3.80)

0.630

Infertility type (%)

0.943

 Primary

60 (27.40%)

16 (29.09%)

18 (27.27%)

26 (26.53%)

 Secondary

159 (72.60%)

39 (70.91%)

48 (72.73%)

72 (73.47%)

Gravidity

2.00 (0.00, 3.00)

2.00 (0.00, 3.00)

2.00 (0.00, 2.00)

2.00 (0.00, 2.00)

0.277

Parity, Mean ± SD (Range)

0.48 ± 0.71 (0.00–3.00)

0.55 ± 0.77 (0.00–3.00)

0.48 ± 0.73 (0.00–3.00)

0.45 ± 0.66 (0.00–3.00)

0.722

No. of miscarriages

1.00 (0.00, 2.00)

1.00 (0.00, 2.00)

1.00 (0.00, 2.00)

1.00 (0.00, 2.00)

0.418

Basal serum FSH (mIU/ml)

6.80 ± 1.99

6.95 ± 2.82

6.98 ± 1.78

6.58 ± 1.49

0.368

AMH (ng/ml)

3.00 (1.90, 4.50)

3.30 (2.10, 5.20)

2.70 (1.90, 3.90)

3.00 (2.10, 5.00)

0.082

No. of retrieved oocytes

16.00 (12.00, 21.00)

16.00 (12.00, 21.00)

15.50 (12.20, 20.00)

17.00 (13.00, 21.80)

0.686

Genetic category (%)

0.548

 Reciprocal translocation

118 (53.88%)

33 (60.00%)

35 (53.03%)

50 (51.02%)

 Robertsonian translocation

41 (18.72%)

6 (10.91%)

14 (21.21%)

21 (21.43%)

 Single gene disorders

60 (27.40%)

16 (29.09%)

17 (25.76%)

27 (27.55%)

Female age at blastocyst transfer (y)

30.49 ± 3.80

31.13 ± 4.33

31.12 ± 3.76

29.71 ± 3.39

0.024

Endometrial thickness on the day of P administration (mm)

10.18 ± 1.99

11.16 ± 2.00

10.20 ± 2.09

9.62 ± 1.71

< 0.001

Endometrial thickness at transfer (mm)

10.45 ± 2.01

9.60 ± 1.68

10.20 ± 2.09

11.09 ± 1.92

< 0.001

Triple-line endometrial pattern on the day of P administration (%)

0.856

 A

196 (89.50%)

50 (90.91%)

58 (87.88%)

88 (89.80%)

 B

23 (10.50%)

5 (9.09%)

8 (12.12%)

10 (10.20%)

E2 on the day of P administration (pg/mL)

124.20 (83.50, 174.80)

127.40 (92.40, 212.00)

122.80 (82.20, 155.50)

117.70 (80.40, 171.60)

0.226

LH on the day of P administration (mIU/ml)

19.30 (12.70, 29.20)

20.70 (14.40, 31.10)

19.70 (12.20, 31.40)

18.10 (12.10, 26.90)

0.744

P on the day of P administration (ng/ml)

1.10 (0.90, 1.40)

1.10 (0.80, 1.30)

1.10 (0.90, 1.40)

1.20 (1.00, 1.60)

0.094

Embryo expansion grade at transfer

3.42 ± 0.86

3.46 ± 0.95

3.52 ± 0.95

3.33 ± 0.74

0.353

Embryo inner cell mass grade at transfer (%)

0.236

 A

15 (6.88%)

1 (1.85%)

6 (9.09%)

8 (8.16%)

 B

203 (93.12%)

53 (98.15%)

60 (90.91%)

90 (91.84%)

Embryo trophectoderm grade at transfer (%)

0.699

 A

1 (0.46%)

0 (0.00%)

0 (0.00%)

1 (1.02%)

 B

117 (53.67%)

26 (48.15%)

37 (56.06%)

54 (55.10%)

 C

100 (45.87%)

28 (51.85%)

29 (43.94%)

43 (43.88%)

Morphology score (%)

0.281

  < 4 BC

147 (67.43%)

36 (66.67%)

40 (60.61%)

71 (72.45%)

  ≥ 4 BC

71 (32.57%)

18 (33.33%)

26 (39.39%)

27 (27.55%)

Day of embryo development at transfer (%)

0.706

 Day 5

156 (71.56%)

38 (69.09%)

49 (75.38%)

69 (70.41%)

 Day 6

62 (28.44%)

17 (30.91%)

16 (24.62%)

29 (29.59%)

Clinical pregnancy rate (%)

131 (59.82%)

25 (45.45%)

42 (63.64%)

64 (65.31%)

0.042

Miscarriage rate (%)

21 (16.03%)

2 (8.00%)

5 (11.90%)

14 (21.88%)

0.187

Live-birth rate (%)

111 (56.63%)

23 (46.94%)

37 (64.91%)

51 (56.67%)

0.177