Table 1 Maternal and fetal characteristics at baseline according to SBP trajectories
Variables | Total population | Low-stable | Low delayed-increasing | Low reverse-increasing | Medium reverse-increasing | Medium-stable | High-stable | P-value |
|---|---|---|---|---|---|---|---|---|
(n = 20,353) | (n = 3893) | (n = 1521) | (n = 4454) | (n = 3352) | (n = 4404) | (n = 2729) | ||
Maternal characteristics | ||||||||
 Age (years) | 27.10 ± 4.38 | 27.18 ± 4.29 | 26.80 ± 4.20 | 26.96 ± 4.43 | 27.07 ± 4.36 | 27.31 ± 4.43 | 27.48 ± 4.60 | <.0001 |
 Early pregnancy BMI (kg/m2) | 21.61 ± 3.11 | 20.21 ± 2.26 | 20.88 ± 2.60 | 22.02 ± 3.11 | 21.03 ± 2.60 | 21.97 ± 3.08 | 23.71 ± 3.94 | <.0001 |
 Gestational age (week) | 38.66 ± 1.30 | 38.74 ± 1.25 | 38.64 ± 1.25 | 38.59 ± 1.33 | 38.81 ± 1.22 | 38.65 ± 1.31 | 38.46 ± 1.44 | <.0001 |
 Primipara (n, %) | 10,868 (51.89%) | 869 (48.01%) | 2389 (55.10%) | 1892 (56.04%) | 1968 (47.62%) | 2139 (50.99%) | 1361 (54.37%) | <.0001 |
 Abortion in previous pregnancy (n, %) | 2684 (13.19%) | 219 (12.10%) | 508 (11.72%) | 437 (12.94%) | 592 (14.32%) | 568 (13.54%) | 360 (14.38%) | 0.0024 |
 GDM (n, %) | 4139 (20.34%) | 279 (15.41%) | 755 (17.41%) | 739 (21.89%) | 682 (16.50%) | 915 (21.81%) | 769 (30.72%) | <.0001 |
 GH (n, %) | 692 (3.40%) | 15 (0.39%) | 8 (0.53%) | 57 (1.28%) | 205 (6.12%) | 50 (1.14%) | 357 (13.08%) | <.0001 |
 Preeclampsia/eclampsia (n, %) | 182 (0.89%) | 25 (0.64%) | 10 (0.66%) | 28 (0.63%) | 30 (0.89%) | 46 (1.04%) | 43 (1.58%) | 0.0004 |
 Thyroid disease (n, %) | 321 (1.58%) | 15 (0.83%) | 75 (1.73%) | 48 (1.42%) | 61 (1.48%) | 58 (1.38%) | 64 (2.56%) | 0.0002 |
 BP measurement times during pregnancy | 8.24 ± 2.12 | 8.24 ± 2.20 | 8.17 ± 2.04 | 8.18 ± 2.07 | 8.41 ± 2.18 | 8.30 ± 2.15 | 8.03 ± 2.10 | <.0001 |
 SBP at first antenatal visit (mmHg) | 118.13 ± 11.28 | 108.51 ± 7.47 | 104.92 ± 9.44 | 118.78 ± 8.85 | 126.42 ± 8.13 | 117.15 ± 7.82 | 129.55 ± 8.16 | <.0001 |
Fetal characteristics | ||||||||
 Girls (n, %) | 10,686 (52.50%) | 921 (50.88%) | 2286 (52.72%) | 1728 (51.18%) | 2181 (52.77%) | 2264 (53.97%) | 1306 (52.18%) | 0.1467 |
 Newborn weight (g) | 3323.52 ± 431.85 | 3296.60 ± 406.76 | 3312.06 ± 426.98 | 3307.89 ± 444.97 | 3345.89 ± 406.46 | 3346.24 ± 431.01 | 3308.93 ± 476.67 | <.0001 |
 1-min Apgar scores | 9.97 ± 0.56 | 9.99 ± 0.80 | 9.97 ± 0.35 | 9.98 ± 0.67 | 9.97 ± 0.54 | 9.95 ± 0.49 | 9.94 ± 0.63 | 0.0176 |
 5-min Apgar scores | 9.96 ± 0.48 | 9.97 ± 0.39 | 9.97 ± 0.39 | 9.96 ± 0.51 | 9.97 ± 0.49 | 9.96 ± 0.47 | 9.94 ± 0.64 | 0.1953 |
 Low birth weight (n, %) | 504 (2.48%) | 28 (1.55%) | 112 (2.58%) | 88 (2.61%) | 83 (2.01%) | 90 (2.15%) | 103 (4.12%) | <.0001 |
 Small for gestational age (n, %) | 1986 (9.76%) | 200 (11.05%) | 435 (10.03%) | 374 (11.08%) | 352 (8.52%) | 348 (8.30%) | 277 (11.07%) | <.0001 |
 Early-term delivery (37–38) (n, %) | 7420 (36.46%) | 635 (35.08%) | 1628 (37.55%) | 1333 (39.48%) | 1337 (32.35%) | 1502 (35.80%) | 985 (39.35%) | <.0001 |
 Pre-term delivery (< 37) (n, %) | 1033 (5.08%) | 74 (4.09%) | 208 (4.80%) | 183 (5.42%) | 160 (3.87%) | 221 (5.27%) | 187 (7.47%) | <.0001 |