The baseline characteristics of RPL couples
A total of 1003 couples with a history of uRPL were included in the study, of which, 799 underwent PGT-A (392 in < 35 years subgroup, 407 in ≥ 35 years subgroup), and 204 were not treated with PGT-A and were considered as controls (142 in < 35 years subgroup, 62 in ≥ 35 years subgroup). Most of the baseline characteristics were comparable in two age subgroups (Table 1). Couples in the PGT-A group had a higher number of previous spontaneous miscarriages than the non-PGT-A patients, both in < 35 years (2[2;3] vs. 2 [2;2], P < 0.001) and ≥ 35 years subgroups (2[2;3] vs. 2 [2;2], P < 0.001). However, this difference was unavoidable given that the more spontaneous miscarriages the couple had, the more likely they underwent PGT-A. In women ≥ 35 years old, the PGT-A group was older than the control group (39[37;41] vs. 38[36;39.25], P < 0.05). Besides, women in the PGT-A group had a lower level of Anti-Mullerian hormone in < 35 years (3.75[2.11;6.45] vs. 5.09[3.25;6.85], P < 0.05) and ≥ 35 years subgroups (1.91[1.10;3.59] vs. 3.17[1.41;5.09], P < 0.05) compared with the control group.
Table 1 Baseline characteristics of PGT-A and non-PGT-A patients with RPL.
|
Recurrent pregnancy loss
|
|
P-value
|
|
PGT-A
|
Non-PGT-A
|
|
<35 years old
|
|
|
|
|
No. of cases
|
392
|
142
|
|
|
Age, [interquartile range]
|
31[28;32.75]
|
30[28.75;32]
|
|
0.430
|
BMI, mean± SD
|
23.23±3.38
|
23.56±3.74
|
|
0.344
|
Prior spontaneous miscarriages, median [interquartile range]
|
2[2;3]
|
2[2;2]
|
|
.000*
|
Ultrasonographic findings
|
|
|
|
|
Total antral follicle count, median [interquartile range]
|
15[10;20]
|
16[11;23]
|
|
0.109
|
Endometrial thickness on hCG trigger day, mean± SD
|
0.88±0.18
|
0.87±0.17
|
|
0.769
|
Laboratory testing, median [interquartile range]
|
|
|
|
|
Anti-Mullerian hormone
|
3.75[2.11;6.45]
|
5.09[3.25;6.85]
|
|
0.001*
|
Follicle-stimulating hormone
|
6.12[5.04;7.15]
|
6.08[5.06;7.15]
|
|
0.759
|
Luteinizing hormone
|
4.60[3.55;6.40]
|
5.58[4.13;8.72]
|
|
0.001*
|
Estradiol
|
35.35[27.12;44.30]
|
34.08[26.10;46.00]
|
|
0.901
|
Total testosterone
|
24.82[17.48;35.49]
|
29.81[21.57;39.54]
|
|
.000*
|
Prolactin
|
16.15[11.62;21.35]
|
14.96[11.00;19.37]
|
|
0.122
|
≥35 years old
|
|
|
|
|
No. of cases
|
407
|
62
|
|
|
Age, [interquartile range]
|
39[37;41]
|
38[36;39.25]
|
|
0.012*
|
BMI, mean± SD
|
24.19±3.20
|
24.79±3.78
|
|
0.181
|
Prior spontaneous miscarriages, median [interquartile range]
|
2[2;3]
|
2[2;2]
|
|
.000*
|
Ultrasonographic findings
|
|
|
|
|
Total antral follicle count, median [interquartile range]
|
10[7;15]
|
11[5.75;19.25]
|
|
0.452
|
Endometrial thickness on hCG trigger day, mean± SD
|
0.88±0.19
|
0.90±0.18
|
|
0.357
|
Laboratory testing, median [interquartile range]
|
|
|
|
|
Anti-Mullerian hormone
|
1.91[1.10;3.59]
|
3.17[1.41;5.09]
|
|
0.004*
|
Follicle-stimulating hormone
|
6.82[5.75;8.28]
|
6.39[5.58;8.03]
|
|
0.258
|
Luteinizing hormone
|
4.58[3.66;5.84]
|
4.43[3.46;5.87]
|
|
0.731
|
Estradiol
|
36.07[27.60;46.00]
|
34.35[25.70;47.41]
|
|
0.693
|
Total testosterone
|
19.49[12.06;28.24]
|
21.54[11.19;29.22]
|
|
0.429
|
Prolactin
|
13.77[10.66;17.41]
|
13.34[9.41;17.51]
|
|
0.431
|
|
|
|
|
|
|
PGT-A, pre-implantation genetic testing for aneuploidy; ICSI, intracytoplasmic sperm injection. *Significant difference.
Basic information of ovarian stimulation protocols and embryo culture
The information of oocyte retrieval and embryo development was shown in Table 2. In <35 years subgroup, couples in the PGT-A group had less oocytes retrieved (12.50[8;17] vs. 16[11;22], P <0.001), but with higher rates of fertilization (68.49% vs. 57.83%, P <0.001) and good-quality blastocyst formation (56.46% vs. 51.74%, P <0.05) compared with the control group. The euploid rate was 49.24% in <35 years subgroup, while it was 33.52% in ≥ 35 years subgroup. There were 15.82% (62/392) couples in <35 years subgroup who could not obtain euploid embryos, while it was as high as 40.54% (165/407) in ≥ 35 years subgroup.
Table 2 Basic information of embryo of PGT-A and non-PGT-A patients with RPL.
|
Recurrent pregnancy loss
|
|
P-value
|
|
PGT-A
|
Non-PGT-A
|
|
|
|
<35 years old
|
|
|
|
|
|
No. of cases
|
392
|
142
|
|
|
|
Oocytes obtained, median [interquartile range]
|
12.50[8;17]
|
16[11;22]
|
|
.000*
|
|
Fertilization rate, n (%)
|
3599/5255(68.49)
|
1378/2383(57.83)
|
|
.000*
|
|
Good-quality embryos
|
|
|
|
|
|
No. D3 embryos, median [interquartile range]
|
5[3;8]
|
5[2;8]
|
|
0.352
|
|
No. Blastocyst, median [interquartile range]
|
5[3;7]
|
4.50[2;8]
|
|
0.725
|
|
Good-quality blastocyst formation rate, n (%)
|
2032/3599(56.46)
|
713/1378(51.74)
|
|
0.003*
|
|
Euploid rate, n (%)
|
652/1324(49.24)
|
|
|
|
|
Patients without euploid embryos, n (%)
|
62/392(15.82)
|
|
|
|
|
Cycles of embryo transfer, median [interquartile range]
|
1[1;2]
|
1[1;2]
|
|
0.010*
|
|
Ovarian stimulation protocols, n (%)
Long
Antagonist
Short
Ultra-long
Others
|
184(46.94)
132(33.67)
61(15.56)
10(2.55)
5(1.28)
|
69(48.59)
51(35.92)
12(8.45)
7(4.93)
3(2.11)
|
|
0.169
|
|
≥35 years old
|
|
|
|
|
|
No. of cases
|
407
|
62
|
|
|
|
Oocytes obtained, median [interquartile range]
|
8[6;12]
|
10.50[4.75;16.25]
|
|
0.137
|
|
Fertilization rate, n (%)
|
2680/3863(69.38)
|
470/706(66.57)
|
|
0.144
|
|
Good-quality embryos
|
|
|
|
|
|
No. D3 embryos, median [interquartile range]
|
4[2;5]
|
3[1;6]
|
|
0.153
|
|
No. Blastocyst, median [interquartile range]
|
3[1;4]
|
2[1;6]
|
|
0.401
|
|
Good-quality blastocyst formation rate, n (%)
|
1247/2680(46.53)
|
240/470(51.06)
|
|
0.071
|
|
Euploid rate, n (%)
|
356/1062(33.52)
|
|
|
|
|
Patients without euploid embryos, n (%)
|
165/407(40.54)
|
|
|
|
|
Cycles of embryo transfer, median [interquartile range]
|
1[1;1]
|
1[1;2]
|
|
0.003*
|
|
Ovarian stimulation protocols, n (%)
Long
Antagonist
Short
Ultra-long
Others
|
114(28.01)
110(27.03)
142(34.89)
7(1.72)
34(8.35)
|
24(38.71)
8(12.90)
17(27.42)
3(4.84)
10(16.13)
|
|
0.012*
|
|
|
|
|
|
|
|
|
PGT-A, pre-implantation genetic testing for aneuploidy; ICSI, intracytoplasmic sperm injection. *Significant difference.
Pregnancy outcomes between PGT-A and control groups.
Among women aged <35 years, the cumulative rates of live birth (53.32% vs. 61.97%, P=0.077) and clinical pregnancy loss (19.64% vs. 18.42%, P=0.888) were similar between two groups. Whereas the cumulative rates of biochemical pregnancies (71.43% vs. 80.28%, P <0.05), clinical pregnancies (64.54% vs. 74.65%, P <0.05) and ongoing pregnancies (54.34% vs. 64.08%, P <0.05) were lower in the PGT-A group compared with the control group. In addition, there were no significant differences in pregnancy outcomes after the initial transfer between the two groups in women aged <35 years (Table 3).
Table 3 Comparison of clinical outcomes in RPL patients aged <35 years old.
|
Recurrent pregnancy loss
|
|
P-value
|
|
PGT-A
(n=392)
|
Non-PGT-A
(n=142)
|
|
Cumulative pregnancy outcomes
|
|
|
|
|
Cycles of embryo transfer, n
|
450
|
221
|
|
|
Live births/women, n (%)
|
209/392(53.32)
|
88/142(61.97)
|
|
0.077
|
Biochemical pregnancies/women, n (%)
|
280/392(71.43)
|
114/142(80.28)
|
|
0.045*
|
Clinical pregnancies/women, n (%)
|
253/392(64.54)
|
106/142(74.65)
|
|
0.029*
|
Ongoing pregnancies/women, n (%)
|
213/392(54.34)
|
91/142(64.08)
|
|
0.048*
|
Pregnancy loss/ biochemical pregnancies, n (%)
|
|
|
|
|
Biochemical
Clinical
First
Second
|
41/280(14.64)
55/280(19.64)
42/280(15.00)
14/280(5.00)
|
18/114(15.79)
21/114(18.42)
16/114(14.04)
5/114(4.39)
|
|
0.876
0.888
0.876
1.000
|
Pregnancy outcomes after 1st ET
|
|
|
|
|
Live births, n (%)
|
170/392(43.37)
|
66/142(46.48)
|
|
0.555
|
Biochemical pregnancies, n (%)
|
246/392(62.76)
|
94/142(66.20)
|
|
0.478
|
Clinical pregnancies, n (%)
|
215/392(54.85)
|
83/142(58.45)
|
|
0.491
|
Ongoing pregnancies, n (%)
|
183/392(46.68)
|
72/142(50.70)
|
|
0.434
|
Pregnancy loss/ biochemical pregnancies, n (%)
|
|
|
|
|
Biochemical
|
31/246(12.60)
|
11/94(11.70)
|
|
0.857
|
Clinical
|
44/246(17.89)
|
16/94(17.02)
|
|
0.876
|
First
|
32/246(13.00)
|
11/94(11.70)
|
|
0.856
|
Second
|
12/246(4.88)
|
5/94(5.32)
|
|
1.000
|
|
|
|
|
|
|
PGT-A, pre-implantation genetic testing for aneuploidy; ICSI, intracytoplasmic sperm injection; ET, embryo transfer. *Significant difference.
Among women aged ≥35 years, the cumulative live birth rate (28.75% vs. 30.65%, P=0.765) was also similar between two groups. However, couples in the PGT-A group had significantly lower cumulative rates of biochemical pregnancies (38.82% vs. 69.35%, P <0.001), and clinical pregnancies (36.36% vs. 50.00%, P <0.05), also a dramatically lower risk of biochemical pregnancy loss (10.13% vs. 32.56%, P <0.05) and clinical pregnancy loss (20.89% vs. 37.21%, P <0.05) than those in the control group, lower biochemical pregnancy rate (33.66% vs. 50.00%, P <0.05) and a lower biochemical pregnancy loss rate (8.03% vs. 35.48%, P <0.001) were also observed after the initial embryo transfer undergoing PGT-A (Table 4).
Notably, the cycles of embryo transfer were significant less in PGT-A women with <35 years old (1[1;2] vs. 1[1;2], P <0.05) and with ≥35 years old (1[1;1] vs. 1[1;2], P <0.05).
Table 4 Comparison of clinical outcomes in RPL patients aged ≥35 years old.
|
Recurrent pregnancy loss
|
|
P-value
|
|
PGT-A
(n=407)
|
Non-PGT-A
(n=62)
|
|
Cumulative pregnancy outcomes
|
|
|
|
|
Cycles of embryo transfer, n
|
260
|
99
|
|
|
Live births/women, n (%)
|
117/407(28.75)
|
19/62(30.65)
|
|
0.765
|
Biochemical pregnancies/women, n (%)
|
158/407(38.82)
|
43/62(69.35)
|
|
.000*
|
Clinical pregnancies/women, n (%)
|
148/407(36.36)
|
31/62(50.00)
|
|
0.049*
|
Ongoing pregnancies/women, n (%)
|
127/407(31.20)
|
20/62(32.26)
|
|
0.884
|
Pregnancy loss/ biochemical pregnancies, n (%)
|
|
|
|
|
Biochemical
Clinical
First
Second
|
16/158(10.13)
33/158(20.89)
24/158(15.19)
9/158(5.70)
|
14/43(32.56)
16/43(37.21)
11/43(25.58)
4/43(9.30)
|
|
0.001*
0.030*
0.118
0.482
|
Pregnancy outcomes after 1st ET
|
|
|
|
|
Live births
|
97/407(23.83)
|
12/62(19.35)
|
|
0.520
|
Biochemical pregnancies, n (%)
|
137/407(33.66)
|
31/62(50.00)
|
|
0.015*
|
Clinical pregnancies, n (%)
|
126/407(30.96)
|
20/62(32.26)
|
|
0.883
|
Ongoing pregnancies, n (%)
|
105/407(25.80)
|
15/62(24.19)
|
|
0.876
|
Pregnancy loss/ biochemical pregnancies, n (%)
|
|
|
|
|
Biochemical
|
11/137(8.03)
|
11/31(35.48)
|
|
.000*
|
Clinical
|
29/137(21.17)
|
8/31(25.81)
|
|
0.632
|
First
|
21/137(15.33)
|
5/31(16.13)
|
|
1.000
|
Second
|
8/137(5.84)
|
3/31(9.68)
|
|
0.428
|
PGT-A, pre-implantation genetic testing for aneuploidy; ICSI, intracytoplasmic sperm injection; ET, embryo transfer.
*Significant difference.
Logistic regression analysis of cumulative clinical pregnancy loss rate and live birth rate.
Consistent with the results of stratification analyses, in women aged <35 years, there was no association found by the logistic regression analysis between PGT-A treatment with cumulative live birth rate or clinical pregnancy loss rate (Table 5), while in women aged ≥35 years. PGT-A treatment was showed to be significantly correlated with decreased cumulative clinical pregnancy loss rate (OR=0.408, 95% CI 0.173-0.966, P <0.05) (Table 6).
Table 5 Logistic regression analysis of the primary outcome in RPL patients aged <35 years old.
Variables
|
Clinical pregnancy losses
|
Live births
|
|
P
|
Odds ratio (95% CI)
|
|
P
|
Odds ratio (95% CI)
|
Assisted reproduction technology
|
|
|
|
|
|
ICSI/IVF
|
|
|
|
|
|
PGT-A
|
0.572
|
0.827(0.429-1.597)
|
|
0.483
|
0.853(0.547-1.330)
|
Age
|
0.726
|
1.017(0.925-1.118)
|
|
0.077
|
0.943(0.883-1.006)
|
BMI
|
0.581
|
1.022(0.946-1.103)
|
|
0.361
|
0.976(0.927-1.028)
|
AMH
|
0.851
|
1.008(0.929-1.094)
|
|
0.831
|
0.994(0.940-1.051)
|
LH
|
0.163
|
0.943(0.868-1.024)
|
|
0.044*
|
1.055(1.001-1.111)
|
T
|
0.515
|
0.995(0.980-1.010)
|
|
0.155
|
1.008(0.997-1.018)
|
Endometrial thickness on hCG trigger day
|
|
|
|
|
|
>1.1
|
|
|
|
|
|
<0.8
|
0.262
|
2.147(0.565-8.160)
|
|
0.774
|
0.901(0.442-1.836)
|
0.8-1.1
|
0.466
|
1.610(0.448-5.789)
|
|
0.082
|
1.787(0.928-3.443)
|
Prior spontaneous miscarriages
|
|
|
|
|
|
2
|
|
|
|
|
|
3
|
0.824
|
0.925(0.464-1.844)
|
|
0.854
|
0.960(0.621-1.483)
|
≥4
|
0.001*
|
3.814(1.764-8.245)
|
|
0.062
|
0.545(0.289-1.030)
|
AFC
|
|
|
|
|
|
5-10
|
|
|
|
|
|
<5
|
0.976
|
1.015(0.383-2.692)
|
|
0.261
|
0.719(0.405-1.278)
|
>10
|
0.156
|
1.577(0.840-2.963)
|
|
0.819
|
1.055(0.669-1.664)
|
PGT-A, pre-implantation genetic testing for aneuploidy; ICSI, intracytoplasmic sperm injection; ET, embryo transfer; AFC, antral follicle count, CI confidence interval. *Significant difference.
Table 6 Logistic regression analysis of the primary outcome in RPL patients aged ≥35 years old.
Variables
|
Clinical pregnancy losses
|
Live births
|
|
P
|
Odds ratio (95% CI)
|
|
P
|
Odds ratio (95% CI)
|
Assisted reproduction technology
|
|
|
|
|
|
ICSI/IVF
|
|
|
|
|
|
PGT-A
|
0.042*
|
0.408(0.173-0.966)
|
|
0.426
|
1.314(0.671-2.574)
|
Age
|
0.126
|
1.140(0.964-1.347)
|
|
.000*
|
0.759(0.688-0.837)
|
BMI
|
0.019*
|
1.142(1.022-1.275)
|
|
0.215
|
0.956(0.891-1.026)
|
AMH
|
0.250
|
1.095(0.938-1.279)
|
|
0.095
|
1.092(0.985-1.209)
|
Ovarian stimulation protocols
|
|
|
|
|
|
Long
|
|
|
|
|
|
Antagonist
|
0.890
|
0.940(0.393-2.250)
|
|
0.674
|
0.880(0.487-1.593)
|
Short
|
0.799
|
1.131(0.439-2.911)
|
|
0.543
|
0.834(0.464-1.498)
|
Ultra-long
|
0.226
|
0.249(0.026-2.369)
|
|
0.048*
|
4.468(1.012-19.731)
|
Others
|
0.140
|
3.444(0.666-17.808)
|
|
0.018*
|
0.210(0.057-0.767)
|
Endometrial thickness on hCG trigger day
|
|
|
|
|
|
>1.1
|
|
|
|
|
|
<0.8
|
0.113
|
4.694(0.693-31.784)
|
|
0.089
|
2.908(0.849-9.958)
|
0.8-1.1
|
0.313
|
2.515(0.419-15.087)
|
|
0.027*
|
3.738(1.160-12.042)
|
Prior spontaneous miscarriages
|
|
|
|
|
|
2
|
|
|
|
|
|
3
|
0.892
|
0.941(0.390-2.269)
|
|
0.837
|
1.056(0.628-1.774)
|
≥4
|
0.516
|
1.538(0.419-5.646)
|
|
0.073
|
0.485(0.219-1.071)
|
AFC
|
|
|
|
|
|
5-10
|
|
|
|
|
|
<5
|
0.837
|
0.904(0.344-2.377)
|
|
0.734
|
0.904(0.504-1.620)
|
>10
|
0.627
|
0.778(0.282-2.146)
|
|
0.607
|
1.202(0.597-2.420)
|
PGT-A, pre-implantation genetic testing for aneuploidy; ICSI, intracytoplasmic sperm injection; ET, embryo transfer; AFC, antral follicle count, CI confidence interval. *Significant difference.