Background
Methods
Inclusion and exclusion criteria
Patient characteristics and clinical definitions
Statistical analysis
Results
Baseline characteristics of the patients
Variables | Group A Twin pregnancies with UFs (n = 191) | Group B Twin pregnancies with previous myomectomy (n = 89) | Group C Twin pregnancies without UFs (n = 1077) | A vs B vs C p-value | A vs B p-value | A vs C p-value | B vs C p-value |
---|---|---|---|---|---|---|---|
Maternal age (year) | 35.2 ± 3.2 | 35.8 ± 2.8 | 33.9 ± 3.1 | < 0.001 | 0.125 | < 0.001 | < 0.001 |
(35,24–44) | (36, 31–43) | (34, 23–45) | |||||
BMI at delivery (kg/m2) | 27.0 ± 2.9 | 27.5 ± 3.6 | 26.9 ± 3.1 | 0.250 | 0.228 | 0.741 | 0.097 |
(26.7, 19.3–35.2) | (27.4, 20.7–41.0) | (26.6, 18–39.3) | |||||
Medical history, number (%) | |||||||
Prepregnancy HTN | 2 (1.0%) | 0 (0%) | 10 (0.9%) | 0.645 | 1.0 | 0.700 | 1.0 |
Prepregnancy diabetes | 2 (1.0%) | 0 (0%) | 3 (0.3%) | 0.227 | 1.0 | 0.166 | 1.0 |
Primiparity | 177 (92.7%) | 78 (87.6%) | 917 (85.1%) | 0.019 | 0.169 | 0.004 | 0.640 |
Previous preterm birth | 2 (1.0%) | 0 (0%) | 14 (1.3%) | 0.542 | 1.0 | 1.0 | 0.617 |
Mode of conception | 0.104 | 0.201 | 0.527 | 0.034 | |||
Natural or TI, COH + TI | 23 (12.0%) | 6 (6.7%) | 163 (15.1%) | ||||
IUI or COH + IUI | 15 (7.9%) | 4 (4.5%) | 86 (8.0%) | ||||
IVF or T-ET | 153 (80.1%) | 79 (88.8%) | 828 (76.9%) | ||||
Chorionicity | 0.370 | 0.185 | 0.327 | 0.542 | |||
Monochorionic | 20 (10.5%) | 5 (5.6%) | 89 (8.3%) | ||||
Dichorionic | 171 (89.5%) | 84 (94.4%) | 988 (91.7%) |
Pregnancy outcomes and obstetric complications
Variables | Group A Twin pregnancies with UFs (n = 191) | Group B Twin pregnancies with previous myomectomy (n = 89) | Group C Twin pregnancies without UFs (n = 1077) | A vs B vs C p-value | A vs B p-value | A vs C p-value | B vs C p-value |
---|---|---|---|---|---|---|---|
GA at delivery (weeks) | 36.0 ± 2.2 | 36.4 ± 1.7 | 36.1 ± 2.1 | 0.657 | 0.570 | 0.808 | 0.394 |
(36.9, 22.6–38.9) | (36.9, 29.1–38.6) | (36.9, 22.1–39.4) | |||||
Sum of birth weight of twina | 4772.1 ± 838.9 | 4895.3 ± 701.0 | 4846.8 ± 811.5 | 0.307 | 0.278 | 0.136 | 0.866 |
(4810, 1172–6920) | (5020, 2530–6670) | (4970,844, 6710) | |||||
Weight difference of twina | 304.8 ± 240.1 | 289.8 ± 228.8 | 284.8 ± 227.5 | 0.601 | 0.702 | 0.327 | 0.744 |
(260, 0–1310) | (250, 0–1140) | (230, 0–1390) | |||||
Delivery < 37 weeks | 103 (53.9%) | 53 (60.0%) | 592 (55.0%) | 0.662 | 0.378 | 0.813 | 0.438 |
Delivery < 34 weeks | 24 (12.6%) | 6 (6.7%) | 115 (10.7%) | 0.340 | 0.142 | 0.451 | 0.282 |
Preterm labor | 78 (40.8%) | 38 (42.7%) | 461 (42.8%) | 0.879 | 0.769 | 0.634 | 1.0 |
Admission d/t preterm labor | 48 (25.1%) | 21 (23.6%) | 299 (27.8%) | 0.558 | 0.781 | 0.482 | 0.459 |
PPROM | 30 (15.7%) | 14 (15.7%) | 167 (15.5%) | 0.996 | 0.996 | 0.914 | 1.0 |
Pre-eclampsia | 22 (11.5%) | 6 (6.7%) | 98 (9.1%) | 0.395 | 0.215 | 0.285 | 0.564 |
Gestational diabetes | 25 (13.1%) | 8 (9.0%) | 91 (8.4%) | 0.122 | 0.322 | 0.055 | 0.843 |
Placenta previa | 6 (3.1%) | 5 (5.6%) | 34 (3.2%) | 0.455 | 0.321 | 1.0 | 0.214 |
IIOC | 5 (2.6%) | 3 (3.4%) | 42 (3.9%) | 0.678 | 0.712 | 0.532 | 1.0 |
>2nd trimester IUFD | 2 (1.0%) | 2 (2.2%) | 16 (1.5%) | 0.738 | 0.594 | 0.755 | 0.651 |
SGA (< 10%)a | 34 (18.0%) | 12 (13.8%) | 165 (15.6%) | 0.608 | 0.385 | 0.389 | 0.759 |
Placenta abruption | 2 (1.0%) | 1 (1.1%) | 9 (0.8%) | 0.930 | 1.0 | 0.676 | 0.549 |
Postpartum hemorrhage | 10 (5.2%) | 7 (7.9%) | 64 (5.9%) | 0.686 | 0.391 | 0.867 | 0.485 |
Peripartum transfusion | 16 (8.4%) | 10 (11.2%) | 109 (10.1%) | 0.695 | 0.443 | 0.512 | 0.716 |
Peripartum ICU care | 23 (12.0%) | 5 (5.6%) | 124 (11.5%) | 0.220 | 0.095 | 0.807 | 0.112 |
Sub-analysis according to the size of UFs
Variables | Group A Twin pregnancies with ≥5 cm UFs (n = 32) | Group B Twin pregnancies with < 5 cm UFs (n = 159) | Group C Twin pregnancies without UFs (n = 1077) | A vs B vs C p-value | A vs B p-value | A vs C p-value | B vs C p-value |
---|---|---|---|---|---|---|---|
Maternal age (year) | 34.9 ± 3.7 | 35.2 ± 3.1 | 33.9 ± 3.1 | < 0.001 | 0.279 | 0.263 | < 0.001 |
(34, 30–44) | (35, 24–43) | (34, 23–45) | |||||
BMI at delivery (kg/m2) | 27.0 ± 3.2 | 27.0 ± 2.8 | 26.9 ± 3.1 | 0.886 | 0.652 | 0.646 | 0.864 |
(26.7, 19.3–34.1) | (26.6, 20.6–35.2) | (26.6, 18–39.3) | |||||
Medical history, number (%) | |||||||
Prepregnancy HTN | 0 (0%) | 2 (1.3%) | 10 (0.9%) | 0.789 | 1.0 | 1.0 | 0.660 |
Prepregnancy diabetes | 0 (0%) | 2 (1.3%) | 3 (0.3%) | 0.173 | 1.0 | 1.0 | 0.127 |
Primiparity | 31 (96.9%) | 146 (91.8%) | 917 (85.1%) | 0.015 | 0.472 | 0.073 | 0.027 |
Previous preterm birth | 0 (0%) | 2 (1.3%) | 14 (1.3%) | 0.810 | 1.0 | 1.0 | 1.0 |
Mode of conception | 0.609 | 0.470 | 0.601 | 0.438 | |||
Natural or TI, COH + TI | 5 (15.6%) | 18 (11.3%) | 163 (15.1%) | ||||
IUI or COH + IUI | 1 (3.1%) | 14 (8.8%) | 86 (8.0%) | ||||
IVF or T-ET | 26 (81.3%) | 127 (79.9%) | 828 (76.9%) | ||||
Chorionicity | 0.113 | 0.113 | 0.049 | 0.760 | |||
Monochorionic | 6 (18.7%) | 14 (8.8%) | 89 (8.3%) | ||||
Dichorionic | 26 (81.3%) | 145 (91.2%) | 988 (91.7%) | ||||
GA at delivery (weeks) | 36.2 ± 1.8 | 36.0 ± 2.3 | 36.1 ± 2.1 | 0.867 | 0.833 | 0.889 | 0.602 |
(36.9, 31.3–38.3) | (36.9, 22.6–38.9) | (36.9, 22.1–39.4) | |||||
Sum of birth weight of twina | 4794.1 ± 628.9 | 4767.6 ± 877.2 | 4846.8 ± 811.5 | 0.259 | 0.837 | 0.361 | 0.156 |
(4810, 3410–5950) | (4810, 1172–6920) | (4970,844, 6710) | |||||
Weight difference of twina | 331.6 ± 236.3 | 299.3 ± 241.2 | 284.8 ± 227.5 | 0.401 | 0.383 | 0.202 | 0.587 |
(255, 0–990) | (260, 10–1310) | (230, 0–1390) | |||||
Delivery < 37 weeks | 19 (59.4%) | 84 (52.8%) | 592 (55.0%) | 0.767 | 0.563 | 0.719 | 0.670 |
Delivery < 34 weeks | 4 (12.5%) | 20 (12.6%) | 115 (10.7%) | 0.744 | 1.0 | 0.769 | 0.495 |
Preterm labor | 15 (46.9%) | 63 (39.6%) | 461 (42.8%) | 0.660 | 0.555 | 0.718 | 0.492 |
Admission d/t preterm labor | 9 (28.1%) | 39 (24.5%) | 299 (27.8%) | 0.691 | 0.660 | 1.0 | 0.446 |
PPROM | 5 (15.6%) | 25 (15.7%) | 167 (15.5%) | 0.997 | 1.0 | 1.0 | 0.907 |
Pre-eclampsia | 3 (9.4%) | 19 (11.9%) | 98 (9.1%) | 0.518 | 1.0 | 1.0 | 0.247 |
Gestational diabetes | 4 (12.5%) | 21 (13.2%) | 91 (8.4%) | 0.121 | 1.0 | 0.346 | 0.055 |
Placenta previa | 0 (0%) | 6 (3.8%) | 34 (3.2%) | 0.537 | 0.592 | 0.621 | 0.632 |
IIOC | 1 (3.1%) | 4 (2.5%) | 42 (3.9%) | 0.679 | 1.0 | 1.0 | 0.504 |
>2nd trimester IUFD | 0 (0%) | 2 (1.3%) | 16 (1.5%) | 0.742 | 1.0 | 1.0 | 1.0 |
SGA (< 10%)a | 5 (15.6%) | 29 (18.2%) | 165 (15.6%) | 0.646 | 0.806 | 1.0 | 0.351 |
Placenta abruption | 0 (0%) | 2 (1.3%) | 9 (0.8%) | 0.750 | 1.0 | 1.0 | 0.642 |
Postpartum hemorrhage | 3 (9.4%) | 7 (4.4%) | 64 (5.9%) | 0.510 | 0.376 | 0.436 | 0.583 |
Peripartum transfusion | 4 (12.5%) | 12 (7.5%) | 109 (10.1%) | 0.525 | 0.315 | 0.559 | 0.390 |
Peripartum ICU care | 2 (6.3%) | 21 (13.2%) | 124 (11.5%) | 0.521 | 0.378 | 0.570 | 0.511 |