Table 3 Comparison between frequency of placental /cord pathology findings in sex pairing groups in terms of twins born at C&W hospital (1493 pairs, n = 2986)
F from FF | M from MM | M from MF | F from MF | P | |
|---|---|---|---|---|---|
n = 925 | n = 1005 | n = 483 | n = 483 | ||
Placenta | |||||
Chorionic villi inflammation | 74 (8.0%) | 112 (11.1%) | 37 (8.0%) | 41 (8.8%) | 0.07 |
Chorionitis | 53 (5.7%) | 89 (8.9%) | 32 (6.9%) | 34 (7.3%) | 0.07 |
Anastomosis | 88 (9.5%) | 144 (14.3%) | 11 (2.4%) | 8 (1.7%) | 0.01 |
Unequal placenta sharing | 47 (30.1%) | 72 (42.1%) | 12 (21.8%) | 11 (20.4%) | 0.01 |
Composite of inflammation | 104 (11.2%) | 160 (15.9%) | 54 (11.6%) | 60 (12.9%) | 0.01 |
Composite placenta lesions | 10 (1.1%) | 23 (2.3%) | 10 (2.2%) | 7 (1.5%) | 0.19 |
Cord composite | < 5(< 0.5%) | 5 (0.5%) | < 5(< 1.0%) | 0 (0.0%) | – |
Placenta others | 11 (1.2%) | 17 (1.7%) | < 5(< 1.0%) | 5 (1.1%) | 0.38 |
Placenta weight, g, mean ± SD | 557.17 ± 231.99 | 558.17 ± 232.75 | 495.46 ± 214.42 | 475.52 ± 215.88 | 0.01 |
Placenta length, cm, mean ± SD | 22.17 ± 4.91 | 22.46 ± 5.24 | 21.55 ± 5.11 | 21.30 ± 5.29 | 0.01 |
Placenta width, cm, mean ± SD | 17.44 ± 3.93 | 17.47 ± 4.20 | 16.36 ± 3.79 | 16.99 ± 4.02 | 0.01 |
Placenta thickness, cm, mean ± SD | 2.16 ± 0.41 | 2.11 ± 0.48 | 2.11 ± 0.54 | 2.08 ± 0.42 | 0.10 |
Cord | |||||
Cord length, cm*, mean ± SD | 25.97 ± 11.98 | 28.08 ± 13.22 | 27.92 ± 12.87 | 27.78 ± 12.58 | 0.01 |
Cord distance from margin, cm, mean ± SD | 4.62 ± 2.39 | 4.53 ± 2.41 | 4.67 ± 2.22 | 4.64 ± 2.15 | 0.75 |
Cord distance from membrane, cm, mean ± SD | 6.45 ± 4.08 | 6.62 ± 3.99 | 6.66 ± 3.89 | 6.30 ± 3.83 | 0.85 |
Cord distance from other cord, cm, mean ± SD | 13.35 ± 5.71 | 14.75 ± 11.52 | 13.68 ± 5.45 | 14.73 ± 8.43 | 0.16 |
Cord insertion type | |||||
Marginal | 612 (75.0%) | 724 (79.5%) | 305 (74.8%) | 338 (78.4%) | 0.13 |
Central | 162 (19.9%) | 143 (15.7%) | 85 (20.8%) | 79 (18.3%) | |
Velamentous | 42 (5.1%) | 44 (4.8%) | 18 (4.4%) | 14 (3.2%) | |